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Can I Change Multiple Hyperlinks At Once

I have a large database of files that are hyperlinked in a File Register
created in excel. All of these files have now been moved to a different
drive, but the folder names etc are the same. Is there a quick way to change
the path of the hyperlink, as to do each one individually would take weeks.

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I have created a database of pressure measurements and was asked to include hyperlinks to pdf documents for each measurement. I at first used the hyperlink function via Insert hyperlink (not the formula =hyperlink).

These files are all located in the same folder as the Database excel file on a network hard drive.

However i keep running into troubles.
For example, hyperlinks keep changing on their own or in some cases, link themselves to random pdf files. Also, When i remove a hyperlink adjacent to another hyperlink, all the nearby hyperlinks are removed simultaneously.

I was thinking of converting all of my hyperlinks to =hyperlink format. Is there any short way to do that? Really i just want to get all the hyperlinks working; Any ideas?

Ok guys, I have never seen this before and it is frusting me like crazy.

I have a database in excel. Each row in my database is usable information that has a link to Word files on our server and the database is saved on the server.

Whenever I move the original file which is on the server anywhere it causes all the hyperlinks to change. I have saved it on my desktop then moved it, and it still changes my hyperlinks. I don't understand why my hyperlinks don't just stay they way I created them.

Is there a way to keep my hyperlinks from changing? If you notice the immediate folder of the filename doesn't change.

Example:
//server/reports/filename

C:/document and settings/user/microsoft/reports/filename

Hello All,

I found a few threads that give great examples of macros that create a list of hyperlinks to files in a folder.

Unfortunately for me I have a folder of about 2,000 files that will be on a USB stick The drive letter changes from PC to PC. So I need a macro that can create a list of hyperlink files that do not contain the drive letter, just the current path that the Excel file running the macro is in.

Here is the code for what works great but is not portable.

Please Login or Register  to view this content.

Thank You All.

I have a spreadsheet in which i hyperlink product item numbers to photos of the product. I want to change the location where I currrently store the photo files. This would render the hyperlinks useless. I have thousands of hyperlinked photo files and I don't really want to go through each hyperlink and edit the hyperlink to reflect the new location of the photo files.

The photo files are stored in folders based on vendor. Vendor A folder may have 200 photo files. Vendor B folder may have 600 photo files, etc.

Is there a way to edit the hyperlinks by group?

Thanks!

I have a database saved as an excel spreadsheet that includes hyperlinks to AutoCAD drawings on my hard drive.

My database worked fine until I recently decided to reorganize my files into more specific folders. Now, when I update my hyoerlinks to the newer and longer file paths, they don't work.

An example of an old file path is:
C:\Program Files\AutoCAD LT 2000\Drawing Files\Avalon Hse\BLSouth\BLSAva51FBA001FTG.dwg

The same file at its new address is as follows:
C:\Program Files\AutoCAD LT 2000\Drawing Files\Avalon Hse\BLSouth\FBA\Version #5\BLSAva51FBA001FTG.dwg

When I use the hyperlink function, it works fine using my old path, and it gives me an error with the new path that reads "cannot find specified file." I am positive that the file path is spelled accurately as I copied and pasted it from the path in Windows Exploer that points to the given file.

Is there something in Excel that limits the length of a file path in hyperlinks? I sure hope there's a way for me to get this database working without having to go badk to my old filing system.

Jearshub

I save excel, word and pdf files in a folder. I have a "master" excel workbook that includes hyperlinks to these files. The oldest file in the folder will be hyperlinked to cell A1 in the "master". The second oldest file will be hyperlinked to cell A2 in the "master"... and repeat all the way down column A. So the most recent file put into the folder will be hyperlinked at the very bottom of column A.

I want to run a macro that automatically includes all additional files added since the last time the macro was run, and hyperlinks them down column A. I don't want it to affect any of the hyperlinks previously

See attachment
I have hyperlinks in A1 to A15. I have a bunch of text in the columns beside the hyperlinks in B1 to G15 (this text relates to the hyperlinks on the same row... so it is important not move the hyperlinks to a different row). When I add new files to the folder I want new hyperlinks in A16 and downwards. I do not want to alter ANYTHING from row 15 above.

Thanks!

Here's the thing:

I have an excel sheet that has about 100 different hyperlinks, and somewhere along the line the source changed. Example:

This is what they now link to:
C:\ABC\123\123.mpp
C:\ABC\192\192.mpp

The above is incorrect, since the files are not located in that drive

F:\ABC\123\123.mpp
F:\ABC\123\123.mpp

So basically, how can I with a few simple steps change the source on all of them still keeping the same folder and file names without having to do each one individually?

Tell me there's a way somebody....

Thanks!!!!!

Hi everyone, new to the forum I have used excel for various things but my knowledge isn't that great so I'm looking for some help or advice.

I have created an Excel worksheet that I am going to use as an index page that will contain hyperlinks to various pdf documents that the user can click on to open the documents they require.

I can insert a hyperlink into a cell in the index document manually by using "ctrl k" and navigating to the file location. This works but is very time consuming as I have lots of links to enter. I have read up on using the hyperlink base feature as this is exactly what I need to help speed up the process but I simply can't get it to work.

Each of the pdf files that I want to link to are stored within a folder that is located on my company's shared drive in the following location (I have removed the actual folder names):

G:\Folder Name\Folder Name\Folder Name\Folder Name\Folder Name\PDF Files

If I put this in as the hyperlink base for the document and type a file name into the address field in the hyperlink editor nothing happens and I get the follwing alert:

"Cannot open the specific file"

If I hover over the cell with the hyperlink, the following path is specified:

file:///\\fafile100vm\shared\$\Folder Name\Folder Name\Folder Name\Folder Name\Folder Name\PDF Files\File Name

Any ideas where I am going wrong here?

One thing I should point out is that some of these folder and file names have spaces in them but I'm not sure if this would cause an issue. From experience of using x copy I know that spaces cause problems and you need to use commas but I have tried putting commas around both the hyperlink base and the file name but this didn't work either.

Any help would be much appreciated and if there is anything else I need to add then please let me know.

Im using Excel 2003 on XP Pro SP3 if that helps.

Many Thanks,

Bryan

Hi,

I'm creating a spreadsheet that hyperlinks to about 50 different documents. Eventually, i want a ** to contain the excel file and all the hyperlinked documents. To get the hyperlinks to run from the **, i had to change all of the hyperlinks within my spreadsheet to the E:\ (this is the drive where my burner is). I then inserted the ** into a different computer (D:\) and none of my hyperlinks work anymore? Is there anyway to make sure that the excel hyperlinks open to the files stored on the **, regardless of which drive it is in?

chris

Hello all,

I have excel file with lots of hyperlinks to .png files. I need macro to download the pictures with specified name and folder. Here is how the file would look like:

So I would like to copy all hyperlink drawings in a row (col C,D,E,F) to corresponding folder (col A) with name from (col B).
So far I have as below:

Please Login or Register  to view this content.

This creates the folders and copy the files but outside the folders. Can somebody help me with this one ?
I can't deal with this by myself.

Regards,

Hi,
I am Pavan Kumar. I have a few thousands of files in a virtual Drive S:
Recently, we have migrated from S Drive to M Drive. I have a lot of files in S Drive which have macros and using these macros, I save these files in different sub folders.

Eg - When I use Ctrl + Shift + I, the file gets saved in a sub folder IR.
When I use Ctrl + Shift + C, the file gets saved in a sub folder Comp.

These macros are written so that they get saved as per the drive specified (S Drive). Now that we have moved to M Drive, I am clueless as to what should be done to move these files to the respective folders. I am manually moving them with Ctrl + X and Ctrl + V.

Is there any way that I can insert a macro in all the excel files which would enable me to operate with these files on the M Drive.

Pvan

Hello all,

I have excel file with lots of hyperlinks to .png files. I need macro to download the pictures with specified name and folder. Here is how the file would look like:

So I would like to copy all hyperlink drawings in a row (col C,D,E,F) to corresponding folder (col A) with name from (col B).
So far I have as below:

Please Login or Register  to view this content.

This creates the folders and copy the files but outside the folders. Can somebody help me with this one ?
I can't deal with this by myself.

Regards,

I have a "master file" which contains all of my recurring work activities. This file has many hyperlinks to other MS Office files that I use on a regular basis. This way, I open the master file in the morning, and as I need access to other files, I simply click on the hyperlink to open the other files as needed.

All files are stored on my network directory.

I used this file yesterday, and saved before shutting down.

However, this morning, I opened the master file and none of the hyperlinks are functioning to launch my other files. I have had this problem before, but it was typically limited to hyperlinks for files that I had been using prior to shut down. This time, none of my links are working. I also know that moving files will affect the hyperlinks and none of my file directories have moved.

Any ideas on what caused the hyperlinks to fail and how I can "globally" reactiviate them without having to edit each one individually? ...since I have dozens of files with hyperlinks, that would be a real time consuming task.

I have a spread sheet that has a colunm of hyperlinked files that I have filtered. I now want to save the hyperlink files I have filtered into a specific folder but It is taking very long because I need to select the hyperlink then the pdf opens, then I save the pdf to a folder and then go to the next hyperlink just below and continue.

Please note that I am copying hyperlinked files from an HTTPs webserver.

Opened a spreadsheet (Excel 2003) I use frequently with numerous hyperlinks in it - almost all pointing to files elsewhere on my C: drive - to find that every hyperlink has been "readdressed" (with the correct filename) to the Excel folder buried in Documents and Settings/Username/Application Data/Microsoft/. Of course, none of the files that the hyperlinks point to reside there! So, two questions please. 1. Is there any way to get all the hyperlinks pointing back to the correct (and, incidently) default file location (at specified under Tools/Options) without doing each one individually?, and 2. what could have caused this to happen in the 1st place - would love to dodge this bit of merriment in the future! Many thanks to any and all.....Dan

Hello,
I have a three tier file Hyperlinking question.
I have a parent Excel 2007 workbook which has many Hyperlinks to what I will call a set of child workbook files. In the child workbook files there are also hyperlinks to another set of files.

In the parent workbook I have created the Hyperlinks to the child files using a Hyperlink Base which works great for linking from the parent to the first set of child files.

The problem I have is that the 1st set of child files needs to somehow inherit or set their hyperlink base to that of the parent file that opened them so that the links in the child files with use the same hyperlink base to open the next set of child files.

Anyone know how I can get an Excel 2007 workbook to inherit or set its hyperlink base to the the parent file that opened it? Very confusing.

The real problem here is that anyone can download these file sets to their local drive from a server to any location on their local drive. I only want them to have to go to the parent file and set the hyperlink base in that one file to be able to have working hyperlinks to all of the other files parent to child. Very confusing. Anyway to do this?

I'm having a small problem with the way hyperlinks work in Excel 2003 and it is causing my macro not to work.

I have a spreadsheet of information, and all of the rows of info are linked the left most column of file names. I want these file names to link to their respective files on my computer.

My first idea was to highlight all the files, and link them all to (T:\files\TEMP.pdf) and then use my macro to change the word TEMP in all the hyperlinks to the hyperlinks .TextToDisplay.

In theory this should work, but the problem is that because I highlighted all the hyperlinks, they are all considered one hyperlink, and not 6000 hyperlinks. Therefore if I remove the hyperlink from the top file, they are all removed, and when my macro runs, it links all 6000 hyperlinks to what hyperlink #1 should have linked to.

Is there any way to make all of these hyperlinks seperate from each other? Or is there a better approach I should be using to do this?

Hi everybody,

My name is Stefan and I have a question (sorry I haven't contributed to this forum yet - this is my first post)...

Let's say I have 100 text files on my hard drive in C:\folder1
Let's presume I have 100 text files on my hard drive in C:\folder2

Each file name from folder 1 is also present in folder 2, but the contents (txt) are different

So here's the question that puzzles me a long time now... when 2 file names residing in different folders are identical, is it possible to append both text files and export them to C:\folder3

I have the following set up in mind
- all file names from folder 1 + file path in column A ... e.g. C:\folder1\text1.txt ... etc
- all file names from folder 2 + file path in column B ... e.g. C:\folder2\text1.txt ... etc

Is there an easy solution to accomplish this with Excel 2003?

BTW, I have no VBA programming skills, so..., much obliged to anyone who can help me out here!

With kind regards,

Stefan

I have a excel spreadsheet that queries an MS SQL db. It fills the DB accordingly but one column represents a list of links to files on my server. How do i set the column to be hyperlinks?

Thanks
redhanz

The problem is that the strings in the DB that represent the path to the file use a virtual share name.
eg.
//path/folder/eg.pdf
excel does not link it unless i change it to:
file://path/folder/eg.pdf

Is there a way to force it to be a hyperlink based on the data in the column.
Thanks
redhanz

Mods: Please move this thread if I have posted in the wrong location. Thanks

I have an Excel file which is a database that is stored on my T:Drive which is a network drive. Only certain individuals have access to the folders and files on these drives. I have created a database excel file that I am trying to put on a website so that people, who do not have access to the T:Drive, can still access the Database file. We have created the remote path that allows for the file to be opened and it works but there are some tweaks that I still need to make.

The major problem I have faced that I would like to get some assistance on is:

The Database has buttons on it that opens up other Excel files that will act as Request forms. Within these forms, there are drop down Validation Lists that populate from information in the Database. The problem is that when the user opens the Database through the Website, the database assumes the remote path of the website that locates the file in the T:Drive which means that the linkage is broken because the links are looking for the Database through the T:Drive path. I tried changing the linkage to look for the database throught the remote path but then the admin has trouble with linkages because he needs to use the database through the T:Drive to make changes.

Does anyone have any ideas on how to fix this error?

Thanks.

Good morning folk

I have the code below to create a list of files in a folder on a sheet,,,,, is there a way to automatically have the file names hyperlinked to the files

Many thanks

JT

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I'm running Excel 2003 on Windows XP Pro SP2. I'm accessing files on a network drive. I recently changed some security settings in Windows for this particular folder so that only certain people had full control. But everyone can open and save changes to the Excel files within this folder. Since that change, I have seen an enormous amount of temp files, with no extension. The file type says "File" and they are all the same number of characters, like "0EF21000". They open up in Excel just fine. But it seems everytime one of the 43 excel files in this folder is open, it creates a new "File". So in a 12 hour period, access to these 43 Excel files have created 375 "File" files. Prior to this security change, I had seen these files as well. Not everytime a file was opened, but there were still quite a few. But NOTHING like it is now.

What is causing these files to be created??? Can I stop it? I know I could write VBA to clean out all non-XLS files daily, but I'm just trying to figure this out first. Is there a setting in Excel that could be causing this?

Hi. Noob here. I have a doc with a very long A Column filled with titles of songs that are stored as audio files on my system, and I'm wanting to change all these mere titles into hyperlinks which would call up RealPlayer (or whatever) and play each audio clip when a title is clicked. I can do that, but each time I right-click/hyperlink, the 'Look In' dialog defaults to My Documents, and I have to browse to the correct folder, which is very tedious. We're talking over 2,500 titles.

Excel Help's entry for the Hyperlink Function didn't seem to address this. I did find a forum discussion about changing the Hyperlink Base by going to File>Info>Show All Properties and entering a path into the Hyperlink Base field, but after doing this, right-click/hyperlink still defaults to My Documents. (I'm thinking maybe this solution was intended for docs with already existing hyperlinks?, which isn't my situation...)

So, how do you get the Insert Hyperlink dialog to open to a different specified folder automatically?

Also, as a bonus, assuming there is a way to change the default folder, would there then be a way to simply select the entire column and convert all the titles to hyperlinks in one operation? Does it help that each title in the column happens to be identical with its corresponding audio file on the drive (well, minus the file extension)? Just trying to keep from doing 2,500 repetitions of anything.

Thanks for any insights. Excel 2010, Vista 64-bit.

- Bob K.

Hey, I hope this is the right place to post this...

Basically I'm putting hyperlinks into an Excel spreadsheet (using Excel 2002). They link to a different file in a shared network drive. However, when the file is sent as an e-mail, and opened by someone else, the file path has changed to the user's local C: drive. I've tried to set the hyperlink base to the folder path, and zipping the file before sending, but it still isn't working properly. I'm using Lotus Notes to send the files.

Any ideas on locking the file path so that it will still retain the proper file path when it is e-mailed?

Thanks.

I have 3 database. Database1 (C is my personal database. Database2 (D is a worldwide shared database which is very slow. and lastly Database3 (J which is a mirror of "D:" for viewing purposes only (cannot copy nor paste in this database). To copy a file from D: to C: what I normally do is go to J: first ,as this drive is 100x faster than D:, to search the files I want to copy. Once I find my target files, I copy the path from J then open that path in D: Drive (e.g., Copy J:\Gelatine\Sugar\Baby.xls and paste in D: Drive as D:\Gelatine\Sugar\Baby.xls) which takes several minutes to load. Once D: Drive is open, I can now copy the file from D to C. (take note J drive is for viewing purposes only.).

What I want to achieve is to make a UI/Userform with 2 textbox and 1 button. Textbox1 is where the user will put the path from J: and textbox2 is the path where the user wants to save the target files from J. Once the button is pressed, this will automatically save the files from J/D to C.

Is this possible?

I am not really sure what vba codes to use.


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# Transverse Wave Calculations

1. Mar 25, 2011

### KatieKT

A transverse wave is described by the expression y= 0.05cos(4.19x-1260t). You may assume all measurements are in the correct SI units.
A) What is the amplitude of this wave?
B) What is the wavelength of this wave?
C) How fast is the wave travelling?
D) What is the maximum tranverse velocity of the wave?

Relevant equations: y= a sin (b(x-c)) +d
Lamda= velocity/frequency
Velocity= delta x/ time

A) the amplitude is 0.05 as "a" in the formula is always amplitude.

I am having trouble figuring out the last three questions but. How you do figure out the wavelength? Do you have to draw the wave on a quadrant graph and get the information off that?

Last edited: Mar 25, 2011
2. Mar 25, 2011

### tiny-tim

Welcome to PF!

hi KatieKT! Welcome to PF!

(have a lambda: λ and a delta: ∆ )

We measure the wavelength at a fixed time

for fixed t, how much do we change x for y to be repeated?

(And we measure the speed at a fixed height

for fixed y, what is the ratio of x to t for y to stay constant?)

3. Mar 27, 2011

### KatieKT

Yeah so in y=a cos(bx + c) + d, a is amplitude and b would be the one that effects the period/wavelength. So is it 4.19m's long? Usually I thought that along the bottom of the graph it's like 45, 90, etc for thesse types of graphs but I don't think that's right.

4. Mar 27, 2011

### ideasrule

Think about what the wavelength means. 4.19x-1260t is the angle being fed into the cosine function, so it should advance by 2pi (representing one cycle) every time x advances by lambda. If we hold t constant, what should lambda be so that this is true? You can use the same reasoning to find the period. Speed would then be wavelength/period.

It's like 45,90,etc. if you plot sine or cosine with the angle on the x axis. In this case, bc+x is the angle being fed into the cosine function. You can definitely plot y=acos(bx+c)+d as a function of this angle, although for this question, I don't see why you would.

PS. Anyways, try to use y=acos(wx-kt). It's much more common and intuitive than y=acos(bx+c)+d, since a, w, and k both have well-defined meanings.

5. Mar 29, 2011

### KatieKT

Ok so i've worked out λ to be 1.49m through 2∏/b. Then the frequency by 1/1.49 to get 0.23Hz. However to get the velocity I was told to use v= -Vmax sin(-1260t) and the formula for the maximum transverse velocity was Vmax= 2∏A/λ. Is 2∏A/λ the correct formula to use however? I know for maximum velocity it is, but is it also the formula for maximum transverse velocity?

format: plain


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How to plot the graph of the function $Re(η(s))$

The Dirichlet $\eta$ function (the alternating zeta function) is given by

$$η(s)=\sum_{n=1}^{∞}(-1)^{n-1}/n^s$$

for $s=x+iy$. I want to plot the graph of the function $Re(η(s))$ (in a specific range of $x$ and $y$) the real part of the function $η(s)$. I am searching for a software or a program available in the net to do this.

-
Did you try the WolframAlpha or Mathematica programm ? –  Mher Mar 8 '14 at 16:38
@MherSafaryan: Ok I will try now. –  DER Mar 8 '14 at 16:39
I've got the graph on $[0,1]^2$, just type this in the text box of the site "Plot3D[Re[eta(x+I*y)] ,{x,0,1},{y,0,1}]" –  Mher Mar 8 '14 at 16:49
@MherSafaryan: Thank you very much. –  DER Mar 8 '14 at 17:05
You're welcome. –  Mher Mar 8 '14 at 17:23


text:
2019
Том 71
№ 2

Subdivision of spectra for some lower triangular double-band matrices as operators on $c_0$

Durna N.

Abstract

The generalized difference operator $\Delta_{a,b}$ was defined by El-Shabrawy: $\Delta{a,b}x = \Delta_{a,b} (x_n) = (a_nx_n + b_{n-1}x_{n-1})^{\infty}_{n = 0}$ with $x_1 = b_1 = 0$, where $(a_k), (b_k)$ are convergent sequences of nonzero real numbers satisfying certain conditions. We completely determine the approximate point spectrum, the defect spectrum, and the compression spectrum of the operator $\Delta_{a,b}$ in the sequence space $c_0$.

Citation Example: Durna N. Subdivision of spectra for some lower triangular double-band matrices as operators on $c_0$ // Ukr. Mat. Zh. - 2018. - 70, № 7. - pp. 913-922.


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# Homework Help: Tricky integral using Partial Fractions

1. Apr 11, 2010

### thomas49th

1. The problem statement, all variables and given/known data
The question asks me to express the integrand in partial fractions to evaluate the integral

$$\int \frac{13x-4}{6x^{2} -x -2} dx$$

2. Relevant equations

3. The attempt at a solution

Well 6x² -x - 2 doesn't factorise (or I cant see it factorised).

So I tried doing long polynomial division and I got something that looked nothing like what the answer is. How should I begin to tackle this problem?

Thanks
Thomas

2. Apr 11, 2010

### Gregg

3. Apr 11, 2010

### Count Iblis

6x² -x - 2 = 1/6 (6x + 3)(6x - 4)

4. Apr 11, 2010

### Count Iblis

And as Gregg suggested you can remove the term linear in x (i.e. 13 x) term from the numerator before you start. That will save you work on the partial fraction expansion:

You can write: 13 = 12 * (13/12)

The numerator can thus be written as:

13/12 (12 x - 48/13) =

13/12 (12 x - 1 + 1 - 48/13) =

13/12 (derivative of denominator -35/13) =

13/12 derivative of denominator - 35/12

So, the integral will be 13/12 Log[6 x^2 - x -2] plus the integral of

-35/12 1/(6 x^2 - x -2)


text:
## elements?!?!

8. [CJ6 14.P.001.] A mass of 135 g of an element is known to contain 30.1 1023 atoms. What is the element?
carbon
hydrogen
oxyden
aluminum

This is the question on my Physics practice test for my exam tomorrow. i don't know where to even begin with this one. we haven't really gone over anything like this in class...

Kevin

 PhysOrg.com science news on PhysOrg.com >> Heat-related deaths in Manhattan projected to rise>> Dire outlook despite global warming 'pause': study>> Sea level influenced tropical climate during the last ice age
 Can u find the no. of moles
 how?

## elements?!?!

1 mole contains 6.02 * 1023 entities here atom

 ok so i am guessing that the equation that i need to use is n=N/NA but how do we figure out N?
 yup, N is given to u 30.1 1023
 ok so we have 5 moles but now what? how do we figure out what element it is?
 Do u now approx mol wt of above given elements Find the Mol wt with the help of Mole equation $$n=\frac{g}{M_0}$$ where M0 is Mol wt and g is the given wt
 so i feel u got M0=135/5=27 Which belongs to ????(WHAT)
 so using the equation you gave me, i have n = 5 and g = 135, so i find Mo, which came out to be 27, and in the periodic table 27 is Co. what element is Co? but i think its wrong...
 now that i know the mol wt, i matched it with the periodic table and it comes out to Co, but which one of the choices are Co.
 U checked in for Atomic Number Rather than atomic wt Atomic wt for Al is 27 (Aluminum) Co is Cobalt
 hehe, that could help if i looked for the right thing. Thanks alot, i really appreciate your help. Kevin[:)]
 Recognitions: Gold Member Science Advisor Staff Emeritus The whole point of a "mole" of an element is that it's weight in grams is equal to the weight of an individual atom in "atomic units". Once you know that you can identify the element.


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# How is angular momentum conserved for rotating systems?

Oct 21, 2015

when external torque acting on a body is zero

#### Explanation:

Angular momentum is defined as rate of change of torque
J=dT/dt ( T- torque ) ,
if external torque acting on a body is zero , then J=d0/dt
but differentiation of any quantity is zero is it is a constant , so angular momentum remains constant is ext. toruqe is zero


text:
# Checkbox

## Checkbox(b)

Defines a variable or table cells to be a checkbox true/false input. The parameter «b» must be a literal value, either 0 or 1. When the user views the definition, or when an input control is created for the variable, the definition displays as a checkbox control -- either an empty square (unchecked) or a square with a checkmark (checked).

When the user clicks on the checkbox control, the value is toggled from 0 (unchecked) to 1 (checked).

To define a variable as a checkbox, you must type the expression directly into the definition field (e.g., Checkbox(0)). Once entered, it will display as a checkbox when viewing the definition field. Typically you would then create an input control for the variable (since the purpose of this function is to provide your users when a checkbox on a form).

### Checkboxes in tables

To define a cell in a table as a checkbox control, view the table from edit mode and then type Checkbox(0).

In Analytica 4.5 and later, it will immediately display as a checkbox control as soon as you enter the expression. An expression-control selector appears along the right edge of the table window, near the top, once the control displays. If you need to change or remove the textual expression, use this control to select Show expressions' from edit mode. In browse mode, the cells will always display as controls. The checkbox control will be disabled in browse mode unless your table node also has an input node associated with it.

In Analytica 4.4 and earlier. When a table is viewed in edit mode, Checkbox and Choice calls display in textual format. When viewed in browse mode, they display as controls. To utilize checkbox controls from tables, you'll need to create an input node for the table, so that the values can be altered when viewing the table from browse mode.

## Examples

A diagram containing a checkbox. Pay_bonus is defined as Checkbox(1):

A table containing checkbox controls. Each cell in the Cogen column is defined as Checkbox(0) or Checkbox(1).

## Notes

When copy/pasting into a table containing checkboxes, if the source data contains values 0, 1, "yes", "no", "true", or "false", the control will remain as a check and just change the current state to match the incoming data. If the source data contains something dramatically different (e.g., 17.3), then the control will be replaced by the value.

If you specify a script attribute for a variable defined using Checkbox, the typescript in that attribute will be executed whenever the user clicks on the control to change its state.

## Limitations

A checkbox provides only a scalar option (true/false). Unlike a Choice pulldown, you do not have an All option to propagate both options through the model. For that option, you'll still need to revert to a Choice.

On a checkbox input control, there is not an option to place the checkbox to the left of the label. If you want this layout, you use Set Node Style... to turn off the label on the input control, and then place a text node with the label to the right of the check.

Checkboxes only display for input controls. You can't use a checkbox to present result information in an output control or result table.

As with other input controls, there is no disabled state (i.e., where the control is visible on a form with a grayed-out appearance, and doesn't respond to user input).

## History

Checkbox was introduced in Analytica 4.2.


text:
SEARCH HOME
 Math Central Quandaries & Queries
 Question from Peggy: How many acres in 2700' circumference or perimeter

Hi Peggy,

The answer to your question depends on the shape of the lot.

For example:

If it is a square then each side is of length $\large \frac{2700}{4} \normalsize = 675$ so the area is $675 \times 675 = 455,625$ square feet.

If the lot shape is a circle then the area is 580,119 square feet.

If the lot is a rectangle measuring 750 feet by 600 feet then its area is 450,000 square feet.

I'm sorry but without knowing the shape I can't answer your question,
Penny

Math Central is supported by the University of Regina and The Pacific Institute for the Mathematical Sciences.


text:
Web Results

## Circumference - Wikipedia

en.wikipedia.org/wiki/Circumference

The circumference of a closed curve or circular object is the linear ... A000796). Pi is defined as the ratio of a circle's circumference C to its diameter d: π = C d {\ displaystyle \pi ={\...

## Relation Between the Circumference and Diameter - eMathZone

www.emathzone.com/tutorials/geometry/relation-between-the-circumference-and-diameter.html

This constant ratio is denoted by Greek letter π . The value of π is 22/7or 3.1415. ∴ Circumference Diameter = π. Or Circumference = π × Diameter = π d Or 2 π r ...

## Geometry Calculating Circle Circumference - Math-Prof.com

www.math-prof.com/Geom/Geom_Ch_31.asp

It is called the circumference AND the perimeter. There is a special relationship between the circumference. and the diameter of any circle. The circumference is  ...

## Circumference - Math Goodies

www.mathgoodies.com/lessons/vol2/circumference.html

Pi is the ratio of the circumference of a circle to its diameter ... This relationship is expressed in the following formula: diameter formula , where diameter is the ...

## Relation between diameter radius and circumference are discussed ...

Relation between Diameter and Radius: What is the relation between diameter and radius? Solution: Diameter of a circle is twice of its radius. Formula: ...

Jun 7, 2015 ... This screencast shows how we can find the relationship between diameter and circumference!

## Circumference and Diameter - StudyZone

www.studyzone.org/mtestprep/math8/e/circumdiameter6l.cfm

## Relationship between Diameter and Circumference | Math | Video ...

www.pbslearningmedia.org/resource/ng09.math.geometry.pla.diameter/relationship-between-diameter-and-circumference/

Using two circles nearby, they compare the diameter of each circle to its circumference. They realize there is a special relationship between the circumference of ...


text:
Home

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A ray of light falls on the su...

Updated On: 20-06-2022

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Text Solution

(alpha-beta)2(alpha-beta)(alpha-beta)//2(beta-alpha)

Step by step solution by experts to help you in doubt clearance & scoring excellent marks in exams.

Transcript

sasur a question that there is array of light ok which falls on the surface of a spherical glass paperweight ok and it makes an angle of Alpha with the normal and is reflected in the medium at angle and Mission of emergent ray from direction of incident ray is we have to find out the deviation in the emergent ray from the incident ray so let me draw a paper wait for you historical paperweight presupposes a spherical paper weight OK so we can see that suppose this is the normal if this is normal then suppose this is the incident ray incident ray it gets incident year

it gets reflected ok and then it emerges ok and then it emerges students in normal wear and normal will be like this ok sunao like this we will see that they are meeting here ok so this is the incident ray the reflected ray and this is the emergent ray ok the it is the the red light Falls at an angle of Sulphur and it is refracted with the angle of Beta this angle will also be angle beta so we have to find the angle of emergent sunao students we can see that in the figure in the first

Fazer deviation by angle this is alpha and this is beta so this is getting created by the angle of angle of Alpha minus beta ok latest make it as angle sunao at the second surface we can see that the deviation is by beta to Alpha ok the angle of deviation is it again and will be of this part will be Alpha minus beta ok so now let me explain to again that if the race getting incident at an angle alpha and this is a refracting angle theta then we can see that change in the angle of we can say debated angle is equal to Alpha minus beta ok and in this case if we consider this as incident ray and this is reflected ray

this will be it is striking normal with angle beta and coming out with angle Alpha so we have to communicate with angle Alpha ok so we can see that the difference ok the deviation will also be for this part will also be Alpha minus beta is this part is also Alpha minus beta so what will be the total deviation what will be the total deviation total division will be equal to division at first part the debate live Asianet second part of it will be too into Alpha minus beta minus 2 is equal to in Two Alpha minus beta is the correct option which is option number 4


text:
# Definition of Density

The density of an object tells you how much matter is in the object, compared to its volume.

The density of water is about $1 \text{kg/L}$. So, $1 L$ of water has a mass of $1 \text{ kg}$. The density of apple juice is about the same. This is really handy to know when you're deciding how much apple juice you can carry when you're walking home from the supermarket.

Anything that is more dense than water will sink if it's placed in water, and anything less dense than water will float in water.

In the picture, the rock sank when it was placed in the bowl of water because it is more dense than the water. The ball floated because it is less dense than the water.

### Description

The aim of this dictionary is to provide definitions to common mathematical terms. Students learn a new math skill every week at school, sometimes just before they start a new skill, if they want to look at what a specific term means, this is where this dictionary will become handy and a go-to guide for a studen

### Audience

Year 1 to Year 12 students

### Learning Objectives

Learn common math terms starting with letter D

Author: Subject Coach
You must be logged in as Student to ask a Question.


text:
# Area of a regular polygon Calculator

## Calculates the area, perimeter, angle and number of diagonal lines of a regular polygon given the side.

 number of sides n n=3,4,5,6,.... side a 6digit10digit14digit18digit22digit26digit30digit34digit38digit42digit46digit50digit area S perimeter L angle θ degree = radian number of diagonals m
 $\normal Regular\ polygon\\(1)\ area:\hspace{50} S={\large\frac{na^2}{4tan({\large\frac{\pi}{n}})}}\\(2)\ perimeter:\ L=na\\(3)\ peak\ angle:\ \theta=180(1-{\large\frac{2}{n}}),\hspace{20} at\ degree\\(4)\ number\ of\ diagonals:\ m={\large\frac{n(n-3)}{2}}\\$

Area of a regular polygon
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[1]  2018/10/21 09:16   Female / Under 20 years old / High-school/ University/ Grad student / Not at All /
Purpose of use
School work
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If you would leave it in radical form that would be great!
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omore flexible and an easier to navigate design
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geometry homework
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not very flexable
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Homework
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i am in 6th grade and doing geometry
why would i not occasionally need help
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study
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need a tutor

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text:
# Challenge: [TGM][TAP] The mfm005's Challenge

Thread in 'Competition' started by Amnesia, 7 Jan 2008.

1. ### AmnesiaPiece of Cake

A new leaderboard is open !

I will introduce a bit an old and great western player who are not very well known because of his discretion : mfm005.

This TGM french player is not deemed for his speed, but he has an incredible ability of stacking..Probably the best of tetrisconcept.
He is a very strange player for his habit to build on the left, and never uses the sonic drop..

So I decided to check if there is somebody here who could get a faster S9 than mfm..On TGM and TAP.

Code:
TGM

--1--cyberguile-----lv. 603
--2--mfm005---------lv. 604
--3--rednefed-------lv. 686
--4--COL------------lv. 710
--5--Ai-------------lv. 72X
--6--Amnesia--------lv. 735

TAP

--1--cyberguile-----lv. 803
--2--mfm005---------lv. 815
--3--rednefed-------lv. 87X
--4--DeHackEd-------lv. 882
--5--Amnesia--------lv. 88X
--6--Rosti LFC------lv. 910

Last edited: 19 Nov 2015
2. ### DIGITALUnregistered

Are there any restrictions? In TGM for example, you can abuse the level stop to stack without raising the level counter. There's no penalty as grade is only based on score.

Also, focusing on combos can really change the style of play. It's not just about stacking perfectly to only score tetrises. Now, you have to stack perfectly to score tetrises in a combo.

3. ### colour_thief

I don't think it's possible to have any restrictions, because abusing level stop and getting combos occurs every now and then even if you're not intentionally milking the system.

4. ### mfm005Unregistered

This is exactly what i've done to achieve this though it doesn't work efficiently in tgm2.

This may only apply for me but when I try to go for combos I tend to have a lower score after all (as I played for score at that time).

I would also like to add the fact that I doesn't (nor can I) play like this anymore and I think Amnesia worship me a little too much as I'm not so great of a TGM player (or maybe we are all great for playing this game at the first place ).

5. ### AmnesiaPiece of Cake

I profite of the good S9 of Rosti to wake up a bit this challenge..

Come on players !! Come and show your real stacking ability without HOLD and other fucking TI features for handicaped..

6. ### COL

These old threads deserve maybe more attention.
COL-TGM1-S9 at level 710

7. ### Ai

Great! Best for me is somewhere around level 850. I'll try post something soon too.

8. ### AmnesiaPiece of Cake

Ai, why did you removed the 2 screenchoot of mfm ?
This forum is sad with so few image..

9. ### COL

The last post before mine had been written on april 2009 and the forum "moved" since. So it isn't surprising that some screenshots disappeared.

10. ### AmnesiaPiece of Cake

The mistake I did in my sentence here is more worrying..

11. ### Ai

If what COL says is corrent then the images must not have made the migration to this new forum. I haven't deleted any images last summer when cleaning up the forum, unless the links were dead.

I looked on mfm005's images page COL posted in the TGM Miscellaneous Challenges thread, but the images are no more. If you still have the images feel free to add them Amnesia. Maybe use an easier leaderboard format to make updating easier. I link to screenshots of the best performances in all my record threads if they are available.

12. ### Ai

I played a few score attack games and I was able to get S9 somewhere around level 720. When I looked it said level 724, probably level 723. I'll try again some other time and post an exact level. I had less luck with the score attack... Only managed to get around 185000 points.

13. ### AmnesiaPiece of Cake

Yesterday I got my first sub-900 S9 on TAP, proof that I really work on the quality of the games now. But I definitely can't get sub 8:30 anymore..
c_t said in the past, that my work on the consistency will one day be 100% returned to me in speed if I work seriously. I hope he is right.

I updated your score Ai, it is hard to know when exactely we break the S9,
generaly it occurs when it is getting hot so you don't have time to waste in watching your level.

14. ### cyberguile

TGM level 708

15. ### rednefed

TAP: level 875 or thereabouts; I know I've certainly done it before 878-880.

TGM: never really bothered to keep track, since S9 is guaranteed for me...

16. ### cyberguile

TGM, level 700

17. ### AmnesiaPiece of Cake

so, lol, 875 ? 878 or 880 ?

This leaderboard is boring, it is too hard to check the exact level, especially on TAP..

18. ### cyberguile

BTW, this was the very first time I didn't met the 500 timer condition lol

19. ### AmnesiaPiece of Cake

Tu n'oseras quand même pas toucher mfm...

20. ### Ai

mfm's best could be outdated. Anyway I updated your score in the score attack thread, cyberguile.


text:
# About functor category and enough injectives.

Let $\mathcal{I}$ be a small category and $\mathcal{A}$ an abelian category. If $\mathcal{A}$ is complete (that is, the product of any set of objects exists) and has enough injectives, how can I prove that the functor category $\mathcal{A}^{\mathcal{I}}$ has enough injectives?

I know that if $R$ is a right adjoint functor to an exact functor $L$ then $R$ preserves injective objects. This may be used to solve the problem; there is a functor $R:\mathcal{A}\rightarrow\mathcal{A}^{\mathcal{I}}$ satisfying the proposition above? If yes, how can I prove it?

If $F(i)\to Q_i$ are inclusive R into injectives for every $i\in I$, then a functor $F:I\to A$ with the values $F(i)$ includes into the product $\prod_i i_*Q_i$. The functor $i_*Q_i$ has the universal property that functors into it are in natural bijection with maps into $Q_i$ in $A$. They're called the right Kan extensions of $Q_i$ along the functors $i:*\to Q$, where $*$ is the one-point category. The explicit formula is $i_*Q_i(j)=\prod_{f:j\to i} Q_i$, and if you don't want to deal with the abstraction of Kan extensions, you can probably prove the claim directly from that formula.
• The right Kan extensions I mentioned are right adjoint to the evaluation functions $A^I\to A$. – Kevin Carlson Oct 7 '17 at 19:59


text:
# How can I make one of the agents to wait X seconds before start moving?

The same script is attached to some multiple agents. On one of them the flag waitToMove is set to true. And it does getting to the line :

StartCoroutine(WaitToMove(10));

But still all the agents including the one with the flag set to true start moving when starting the game.

How can I make that agents with the script that the flag waitToMove is set to true will wait X seconds one agent will wait 5 seconds other will wait 3 seconds and this one will wait 10 seconds ?

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.AI;

public class AgentControl : MonoBehaviour
{
public List<Transform> points;
public bool waitToMove = false;

private int destPoint = 0;
private NavMeshAgent agent;
private Transform originalPos;

void Start()
{
agent = GetComponent<NavMeshAgent>();

// Disabling auto-braking allows for continuous movement
// between points (ie, the agent doesn't slow down as it
// approaches a destination point).
agent.autoBraking = false;

originalPos = transform;

if (waitToMove == false)
{
GotoNextPoint();
}
else
{
StartCoroutine(WaitToMove(10));
}
}

void GotoNextPoint()
{
// Returns if no points have been set up
if (points.Count == 0)
return;

// Set the agent to go to the currently selected destination.
agent.destination = points[destPoint].position;

// Choose the next point in the array as the destination,
// cycling to the start if necessary.
destPoint = (destPoint + 1) % points.Count;
}

void Update()
{
// Choose the next destination point when the agent gets
// close to the current one.
if (!agent.pathPending && agent.remainingDistance < 1f)
GotoNextPoint();
}

IEnumerator WaitToMove(int WaitTime)
{
yield return new WaitForSeconds(WaitTime);
}
}

• Your WaitToMove function does nothing at all after waiting, it just ends. None of the rest of your script - which continues running while WaitToMove is waiting - ever checks whether WaitToMove is still waiting, so it's unclear to me how you expected this code to accomplish anything at all. May 13 '20 at 19:24

Can you do something like this instead?

   //two vars for handling timer
float timer = 0;
//notice WaitTime is a float now
float WaitTime = 10f;
void Start()
{
agent = GetComponent<NavMeshAgent>();

// Disabling auto-braking allows for continuous movement
// between points (ie, the agent doesn't slow down as it
// approaches a destination point).
agent.autoBraking = false;

originalPos = transform;

}

void Update()
{
// Choose the next destination point when the agent gets
// close to the current one.
if (!agent.pathPending && agent.remainingDistance < 1f)
{
//if wait to move is true
if (waitToMove)
{
//if timer is less than 10
if (timer < WaitTime)
{
//add Time.deltaTime each time we hit this point
timer += Time.deltaTime;
}
//no longer waiting because timer is greater than 10
else
{

waitTomove = false;
}
}
//if we hit here waitToMove is false, so go ahead as usual
else
{
GotoNextPoint();
}
}

}

If you want to make the agent wait again after the first time, you will need to set the timer equal to 0 again and set WaitToMove to true, but you can ofcourse add a small function that handles this, infact I'd recommend it.

If you are wanting to randomize the waitTime you can do something like this

//define min and max WaitTime
float waitMinTime = 1f;
float waitMaxTime = 10f;
void Start()
{
agent = GetComponent<NavMeshAgent>();

// Disabling auto-braking allows for continuous movement
// between points (ie, the agent doesn't slow down as it
// approaches a destination point).
agent.autoBraking = false;
//set WaitTime to equal a random number between min and max
WaitTime = Random.Range(waitMinTime, waitMaxTime);
originalPos = transform;

}

So you mentioned in the comments that you also want to add the Objects original position to the end of the list, so when it is finished it will return the its starting position, a patrol.

But you are not doing this you are adding the objects transform reference to the list, this transform is attached to the object so it will be wherever the object is, leading to mini stuttering as it arrives at the original position AND starts moving to it in between frames.

You can test this to see what I mean, leave your code as it is, take one of the transforms 'points' in your level and move it, the agent moves to where the point currently is right? Now Imagine that 'point' is attached to the Agent itself, you might be able to see why its stuttering!

You need to take a snap shot of the position once, and add that I would do it something like this.

Also because you are adding a list of transforms and not a list of positions (Vector3) we will need to create a new GameObject (with transform, they both exist together)

void Start()
{
agent = GetComponent<NavMeshAgent>();

// Disabling auto-braking allows for continuous movement
// between points (ie, the agent doesn't slow down as it
// approaches a destination point).
agent.autoBraking = false;
//set WaitTime to equal a random number between min and max
WaitTime = Random.Range(waitMinTime, waitMaxTime);

//transforms dont exist without A GameObject and a GameObject doesn't exist without a transform
//create a new GameObject to hold our position
GameObject originalPositionObject = new GameObject();
//set the new gameobjects position equal to where the transform is right now
originalPositionObject.transform.position = transform.position;


text:
block design to test two factors with limma
1
1
Entering edit mode
jfertaj ▴ 30
@jfertaj-8566
Last seen 8 months ago
United Kingdom

Hi, I have posted a similar question few months ago applying voom + limma to a block factor design in RNA-seq experiment, but now I have a doubt if the no differences observed between cases and controls are real or caused by my design or by my misuse of block and duplicateCorrelation

My metadata looks like this one:

   sample_ID location sex polyp_type age  status     files
1   INTP_103 proximal   1          1  31    ctrl INTP_1031
2   INTP_103   distal   1          1  31    ctrl INTP_1032
3   INTP_103   rectum   1          1  31    ctrl INTP_1033
4   INTP_105 proximal   2          3  66 disease INTP_1051
5   INTP_105   distal   2          3  66 disease INTP_1052
6   INTP_105   rectum   2          3  66 disease INTP_1053
7   INTP_106 proximal   1          2  64 disease INTP_1061
8   INTP_106   distal   1          2  64 disease INTP_1062
9   INTP_106   rectum   1          2  64 disease INTP_1063
10  INTP_111 proximal   2          1  49    ctrl INTP_1111

Basically I have samples from controls and individuals with a disease, each of the individuals (both control and diseases) have 3 samples from the same tissue but different location. I want to test differences between locations, between cases and control, and between interactions (disease status and location), here is my code

y <- DGEList(txi_longScaled$counts) # the counts come from a kallisto experiment y <- calcNormFactors(y) age <- metadata$age
sex <- factor(metadata$sex) Treat <- factor(paste(metadata$status, metadata$location, sep=".")) design <- model.matrix(~0+Treat + sex + age) design2 <- model.matrix(~1+status + sex + age) colnames(design)[seq_len(nlevels(Treat))] <- levels(Treat) colnames(design2) <- c("Ctrl", "Disease", "sex", "age") # Apply voom v <- voom(y, design) v2 <- voom(y, design2) #Then we estimate the correlation between measurements made on the same subject corfit <- duplicateCorrelation(v, design, block=metadata$sample_ID)
corfit2 <- duplicateCorrelation(v2, design2, block=metadata$sample_ID) # Apply voom taking in account block effect ### remove correlation from the models v <- voom(y, design, block = metadata$sample_ID, correlation = corfit$consensus) v2 <- voom(y, design2, block = metadata$sample_ID, correlation = corfit2$consensus) vfit <- lmFit(v, design, block = metadata$sample_ID, correlation = corfit$consensus) vfit2 <- lmFit(v2, design2, block = metadata$sample_ID, correlation = corfit2$consensus) ## Specifigy contrasts cm <- makeContrasts( CtrlvsCasesProximal = ctrl.proximal - disease.proximal, CtrlvsCasesDistal = ctrl.distal - disease.distal, CtrlvsCasesRectum = ctrl.rectum - disease.rectum, Ctrl.proximalvsCtrl.rectum = ctrl.proximal - ctrl.rectum, Ctrl.distalvsCtrl.proximal = ctrl.distal - ctrl.proximal, Ctrl.distalvsCtrl.rectum = ctrl.distal - ctrl.rectum, Dis.proximalvsDis.distal = disease.proximal - disease.distal, Dis.proximalvsDis.rectum = disease.proximal - disease.rectum, Dis.distalvsDis.rectum = disease.distal - disease.rectum, levels=design) ## Apply limma eBayes to voom objects vfit <- contrasts.fit(vfit, cm) efit <- eBayes(vfit) efit2 <- eBayes(vfit2, robust = TRUE) Are these designs correct? Or should I use just one single contrast and then extract the coefficients, I mean, something like this:? design3 <- model.matrix(~0+location + status + sex + age + metadata$sample_ID)
v3 <- voom(y, design3)
vfit3 <- lmFit(v3, design3)
efit3 <- eBayes(efit3, robust = TRUE)
limma voom • 1.6k views
0
Entering edit mode

What is Treat? Don't rely on information defined in previous posts.

0
Entering edit mode

Post updated @Aaron Lun

2
Entering edit mode
Aaron Lun ★ 27k
@alun
Last seen 3 hours ago
The city by the bay

This data set looks exactly the same as the one discussed in applying voom + limma to a block factor design in RNA-seq experiment. You should have just raised a comment there if you wanted more clarification on the parametrization that I proposed in my answer to that post.

Anyway, if you want to test the interaction terms, design is the only parametrization you can use. Moreover, if you believe that there is a non-zero interaction between location and disease status, then design is the only correct parametrization - not just for testing the interaction terms, but also for testing the effect of location and disease status, given that those effects depend on each other. design2 is inappropriate as it does not consider the effect of location at all, while design3 assumes that the effects are strictly additive.

Assuming that you are using design, the downstream code looks correct. Note that you should have filtered out low-abundance genes prior to calling calcNormFactors. It also wouldn't hurt to run eBayes with robust=TRUE for vfit.

As for why you don't have any DE genes... well, maybe that's because there are no DE genes between the disease and control conditions. The other possibility is that you don't have enough power. Try to think of some positive control genes and see how they behave. I also assume that you have many more samples than the 10 you've shown above, otherwise power will be a serious issue.

0
Entering edit mode

Thanks Aaron Lun, yes I have filtered out low-abundance genes and I have 135 samples, although only 56 controls but I think is enough to get an idea of DEG, and last question, there is no way to test all control vs all disease samples? could I modify somehow design2 to correct for location and test all controls vs all patients?

0
Entering edit mode

You can easily test for the average of all control-related groups to the average of all disease-related groups:

con <- makeContrasts((ctrl.proximal + ctrl.distal + ctrl.rectum)/3 -
(disease.proximal + disease.distal + disease.rectum)/3, levels=design)

... though any non-zero interaction effect will make it difficult to interpret the results of this contrast. This difficulty will be present regardless of what design you use. An alternative approach would be to do an ANODEV:

cm <- makeContrasts(
CtrlvsCasesProximal = ctrl.proximal - disease.proximal,
CtrlvsCasesDistal = ctrl.distal - disease.distal,
CtrlvsCasesRectum = ctrl.rectum - disease.rectum, levels=design)

.. with coef=NULL in topTable. Then you can figure out if DE genes are being driven by changes between case/control in one location or all locations, based on the size of the log-fold changes. A further step-up in rigour would involve testing each contrast in cm separately, and then combining the statistics with classifyTestsF, but this relies on the presence of DE genes between pairwise comparisons, and you weren't getting any of those in the first place.

0
Entering edit mode

Thanks a lot Aaron for the detailed answer!!


text:
November 18, 2020

Analysis

# The Student Debt Crisis is a Crisis of Non-Repayment

Think of the student debt crisis as an overflowing bathtub. On the one hand, too much water is pouring in: more borrowers are taking on more debt. That is thanks to increased demand for higher education in the face of rising tuition, stagnant wages, diminishing job opportunities for those with less than a college degree, and the power of employers to dictate that would-be hires have the necessary training in advance. On the other hand, the drain is clogged and too little water is draining out: those who have taken on debt are increasingly unable to pay it off.

The last post in the Millennial Student Debt project used a new database of student debtors and their loan characteristics (matched to demographic and economic data in the American Community Survey) to document the former phenomenon, both in aggregate and particularly as it pertains to disadvantaged communities along multiple dimensions. Specifically, it showed the rapid growth of student debt levels and debt-to-income ratios in the population at large, among people of all income levels. But this growth is concentrated among non-white borrowers, who have higher debt conditional on income and whose increased indebtedness over the past decade-plus is greater than for white borrowers. That racial disparity is particularly pronounced in the middle of the income distribution. It also showed that student-debt-to-income ratios have grown fastest in the poorest communities since 2008. This post uses the same data to document the latter: non-repayment by student loan borrowers is getting worse over time, especially so for non-white debtors.

Over the last ten years, as outstanding student loan debt has mounted and been assumed by a more diverse, less affluent group of students and their families than was the case for prior cohorts, a common policy response has been to wave away its impact on wealth, both individually and in aggregate, by saying that the debt finances its own repayment. First of all, so the claim goes, student debt finances college degrees that in turn pay off in the form of higher earnings, enabling debtors to repay. Second, expanded allowance for income-driven repayment (IDR), by capping debt service as a share of disposable income, eliminates the worst forms of delinquency and default. The first claim says that repayment is inevitable, the second that it need not take place. Both claims together, however, serve to rationalize higher debt, higher tuition, higher attainment, and the forces driving all three.

IDR was designed to address a liquidity crunch: since students are graduating with more debt, they may not earn enough immediately upon entering the workforce to pay it down. That failure of earnings to align with debt service obligations means that a program to defer those obligations until earnings are realized would ameliorate delinquency and default, at the cost of capitalizing unpaid interest into a higher principal balance. The creation and expansion of IDR programs in the early 2010s did indeed serve to stop the growth of delinquency by the mid-2010s and reverse it, to the point that the share of accounts delinquent now is lower than it was before the Great Recession, despite the amount of debt and the number of debtors having increased continuously since then. For that reason, many higher education policy analysts have proposed further expanding the program.

But IDR programs will never be successful as a solution to the student debt crisis, because they’re designed to address a liquidity problem rather than the real problem—solvency. The problem with student debt is a problem of wealth—students and their families are taking on debt because they don’t have enough wealth to afford increasingly-costly, increasingly-mandatory higher education. The debt then itself exacerbates wealth disparities that the higher education it “paid for” doesn’t rectify.

Moreover, we now have experience with steadily-increasing student indebtedness extending over two whole business cycles, through the expansion of the 2000s, the Great Recession, the long, slow recovery of the 2010s, and now, the current Covid recession. Any idea that temporary economic downturns were responsible for the crisis of non-repayment, and progress would be made up during expansions when labor markets are tight, has now been definitively disproved. What we’ve considered to be economic prosperity of the last ten years, prior to the pandemic, was in fact economically punishing to younger cohorts forced through the wringer of increasingly costly higher education and into a labor market characterized by stagnant wages and deteriorating job ladders.

The fact that balances continue to grow and not be paid back shows that shifting the cost of higher education onto the backs of students, through state budget cuts, slack labor markets, and employer monopsony power, has resulted in a structural attenuation of the economic life cycle: balances carried further into mid-life, or taken on later in life to finance further education or a family member’s education, impairing economic wellbeing for a widening and diversifying swathe of the population, inhibiting savings, increasing precarity, and draining the very incomes the student debt was supposed to increase.

Student debt cancellation is inevitable, in part because it’s already happening: a larger and larger fraction of the loans originated in any given year are not going to be repaid at all, and many more will never be fully repaid. For example, as is shown below, 63.8% of the loans originated in 2018 already had higher balances than they did at origination by June 2019. That number is similar, around 60% and rising, for loans originated between 2013 and 2015, meaning that repayment should have begun following any deferment period, but in fact it has not. Rising IDR enrollment corresponds to deteriorating repayment trajectories and growing loan balances over time.

The policy question is then not whether to cancel student debt, but how? Are we going to rely on increasing IDR and thus kick the ball further into the future, ruining more and more lives as we do so, while still not actually collecting on the government’s loans and potentially imposing a large tax liability when the debt is finally cancelled? Or can we honestly confront and solve a past policy failure in the present by cancelling debt now (and not taxing it), to prevent the debt spiral from getting any worse and rectifying the damage student debt does to household wealth?

IDR, and even modest cancellation proposals that still leave many borrowers with unpaid loans, underestimate the crisis of non-repayment and rest on the false assumption that entrance into the labor market allows borrowers to achieve solvency. The debate that is trendy to have now—whether cancellation at all is inequitable, how it can be structured to ensure it’s equitable—needs to be compared to a baseline in which the consequences of not cancelling debt are understood to be escalating debt peonage, exacerbating wealth inequality, followed by inevitable cancellation, because the debt won’t be paid back.

### Data

For this project, we have assembled a dataset that consists of individual credit reports linked to demographic and economic data reported from the American Community Survey using the subject’s zip code. The credit reports are available in several formats: we have both loan-level data and individual consumer-level data. We also have both panel and cross-section data. For the panel data, one million consumers between the ages of 18 and 35 with a positive student loan balance were sampled in 2009, and then followed through 2019. For the cross-section data, one million consumers in that same age range are sampled, independently, in each year from 2009 to 2019. The loan-level data consists of the loans of all of these people, and the loans are linked to individuals with a unique consumer ID.

### Analysis

###### Figure 1. For the panel data cohort, this chart tracks outstanding student loan balance as a share of the “initial” 2009 balance, so a value of 1 indicates that an individual has the same amount of student debt outstanding in a given year as they did in 2009. Quantiles of the distribution of that ratio (computed year by year) are plotted over time.

We look first at the panel data cohort, that is, one million individuals (between 18 and 35 years old) with student debt outstanding in 2009. For this chart, it’s important to keep in mind that the standard repayment schedule for student loans is a ten-year uniform payment plan, akin to a fixed-rate mortgage.

We compute the ratio of the amount of student debt outstanding in each year as a share of that individual’s initial loan balance in 2009. We then compute the quantiles of the distribution of that ratio in each year. Figure 1 plots those quantiles over time. The blue and red lines show progress toward repayment for individuals who were probably already on the path to repayment when they were observed in 2009. Approximately 40% of the individuals with outstanding student debt in 2009 had paid off all of their student debt by 2019, within the standard ten-year repayment window (or sooner, given that they were probably already well into repayment in 2009).

The green line, the median of the distribution, by contrast, declines slowly and reaches 0.37 by 2019. That means that over 50% of the borrowers with outstanding debt in 2009 hadn’t fully paid back their student loans ten years later. The 75th percentile stands at 1.3 in 2019, meaning that more than 25% of borrowers with outstanding student debt in 2009 had a larger student loan balance ten years later. The 90th percentile is much higher: 3.78, almost four times as much debt outstanding in 2019 as in 2009.

The lack of progress toward repayment can be caused by a number of different behaviors, as well as any combination of them: delinquency, enrollment in an IDR plan, and taking on more debt after these individuals were first observed in 2009 by re-enrolling, and thereby likely deferring payments on prior student loans. Given the age parameters of the dataset, it’s likely that a number of borrowers in the 2009 cohort were yet to complete their education at that point, and thus subsequently took out more loans. It’s common for student loans to increase in principal balance over their first few years after origination, due to deferral. On the other hand, the individuals in this cohort sample don’t change over time. Their minimum age in 2009 was 18, so the minimum age of this group in 2019 is 28. Taking on more debt as they get older makes them less likely to pay off the debt they already had. And that pattern of behavior becomes more pronounced for subsequent cohorts, though this dataset does not directly track them over the full ten-year period that we have for the initial 2009 panel cohort.

Figure 2-5 from a recent Congressional Budget Office report on IDR shows a similar pattern. That chart plots progress to repayment by what CBO calls the “2012 cohort,” which means individuals who began repayment in 2012 (and thus excludes the deferment period on those individuals’ loans prior to that year). That report compares individuals who remained in the standard 10-year repayment plan throughout to those who utilized one of the IDR programs. The former saw their balance decline over time, while, not surprisingly, the latter group’s balance increased. That appears to confirm the interpretation of Figure 1 that a major contributor to the lack of progress toward repayment for many borrowers is enrollment in an IDR plan.

Again, the purpose of IDR is to prevent a liquidity problem by deferring payments. The alternative is much higher delinquency and default rates than there would otherwise have been, so in that sense, the various IDR programs are a success on their own terms. But they are a failure insofar as they give rise to mounting balances over time, rather than facilitating repayment on a delayed schedule more favorable to borrowers. The structure of IDR—capped payments as a percentage of income in the present, possible cancellation of remaining balance in the far future—presumes that those entering into the program will eventually earn a high enough income to cover their full interest and principal loan payments before the date at which their loans would be cancelled. But many borrowers enter into IDR with no intention or prospect of ever leaving it. In fact, the program itself contains an incentive not to exit it: the cancellation at the end, the balance of which the borrower would otherwise be responsible for. That is why a great deal of student debt cancellation has already been committed to and a rising share of new student loans will never be repaid. The policy question is essentially whether to continue to insist on futile interest payments in the meantime, or to recognize that the underlying debts are un-repayable now. Trying to push people out of IDR programs once they’ve structured their lives and careers to conform to their terms, in order to improve the prospects of repayment, as some have proposed, would likely lead to a flood of delinquencies, as better-paid jobs are hardly abundant and available for the asking in a monopsonized labor market. In any case it would be unfair to borrowers who’ve done as they were told by policy-makers, when in reality it was the policy-makers whose failures led to the crisis of non-repayment.

The lack of progress toward repayment means that many student loans increase in balance over their lifetime, the opposite of the standard repayment structure in which, following any deferment, principal is steadily drawn down by uniform loan repayments until the loan reaches a principal balance of zero upon full repayment. Thus, another window on the non-repayment of student loans is the share of loans that have a higher principal balance than they did when they were originated. The loan-level data in our credit reporting dataset enables us to compare the current balance on a loan when observed in the dataset to the balance of that loan at origination.

###### Figure 2.

Figure 2 plots the percentage of loans at each observation date that had a higher balance at that point than they did at origination. This is taken from the loan-level cross section data, as opposed to the panel data used for Figure 1. In each year, one million individuals with student debt between the ages of 18-35 are observed, along with all of their student loans. The yellow series shows the share of student loans in each year of the cross section in which the current balance exceeds the starting balance.

The credit reporting data also includes each individual’s zip code. We match that to zip code-level demographic data from the American Community Survey to try to see how non-repayment differs by race. The pink series shows that same share of loans for individuals who reside in zip codes that are majority white, and the purple series shows that share for individuals who live in majority-minority zip codes. Even though there’s no direct information about the race of the actual individuals in the credit reports, and plenty of non-white people live in majority-white zip codes, while a smaller but still significant share of white people live in majority-minority zip codes, we can be fairly certain from this data that non-repayment is concentrated among non-white borrowers, as measured by loans with a higher balance than their original balance. That racial gap in non-repayment is significant throughout and rises slightly over time even while the overall rate of non-repayment also rises. (Note the kink point in 2016, after which non-repayment across all zip codes increases dramatically.) It’s the case that borrowers with higher balances are likelier to enroll in IDR because the savings from doing so is greater the higher the payments you would otherwise have to make, and higher-balance borrowers are, in general, higher-income. Still it’s also very likely that non-white borrowers are more likely to have enrolled in IDR, since they carry more debt conditional on income than white borrowers do. The pattern depicted in Figure 2, both over time and in the cross-section of zip codes, is consistent with that inference.

One concern with this metric as a measure of non-repayment is that loans in deferment increase their principal balance as a matter of course, and ‘younger’ loans are more likely to be in deferment. Therefore, it’s theoretically possible that an increasing share of loans with a higher current balance than initial balance reflects the changing age distribution of loans: more loans are taken out cohort-by-cohort, so over time, an increasing share of student loans would be younger and thus more likely to be in deferment. In plotting non-repayment through the share of loans where balances exceed the original, a greater share of student loans would appear by this metric to be in non-repayment status due to a rising share of loans in deferment, not IDR, delinquency, or some other reason pertaining to the non-repayment of loans over their term.

Figure 3 addresses this concern by illustrating how the student loan age distribution has changed over time. It’s getting older, not younger—itself evidence of declining repayment, and suggesting that the non-repayment or “level” effect outweighs the increased-origination or “composition” effect. Note especially the rising share of loans that are 10+ years old, which is to say, older than the term in which a traditional student loan is supposed to be paid off.

To return to the bathtub metaphor, overall, the water in the tub is getting ‘older’ because the ‘old’ water that isn’t draining out and thus remains in the tub for longer counteracts the ‘young-ness’ of the ‘new’ water pouring in. The implication for Figure 2, then, is that even though you’d expect more loans to be out of deferment and in repayment due to the mix of loans getting older, we still see increasing balances and therefore not actual repayment. And that, in turn, is further evidence that if we had 10 years of panel data for subsequent cohorts following the 2009 cohort depicted in Figure 1, that data would show even worse progress toward repayment for those younger cohorts.

###### Figure 3. The age distribution of the loans in each year of the cross-section (amounting to a million student loan borrowers per year, including all of their loans) has been getting older over time.

Figure 4 is a further illustration of the phenomenon of non-repayment similar to Figure 2. In this case, years refer to the loan’s origination year (its “vintage”), and the horizontal axis tracks the years since that initial origination year. Thus, we have longer series in the data covering 2009-2019 for loans originated near the start of that time period. As we can see, the share of loans with a higher current balance than initial balance rises vintage-by-vintage. All the vintages show an initial increase within the first few years, likely reflecting high prevalence of deferment for younger loans. They then level off, until the year 2016, which is a kink point for all vintages (thus reflecting the same pattern as in Figure 2). After that year, every vintage includes more loans with a higher current balance than initial balance, despite the fact that each vintage is getting older. And, most importantly, this metric shifts up with each vintage, suggesting that non-repayment is getting worse both over time and across vintages.

###### Figure 4.

The kink point in 2016 likely reflects the expansion of IDR programs toward the end of the Obama administration, with the creation of the REPAYE program and aggressive marketing of other IDR programs as a solution to delinquency, as detailed in the aforementioned CBO report.

Figure 4 is essentially the mirror image of Figure 15 from the 2015 paper “A crisis in student loans? How changes in the characteristics of borrowers and in the institutions they attended contributed to rising loan defaults” by Adam Looney and Constantine Yannelis. That figure is reprinted below. It tracks loan repayment for successive repayment cohorts (defined, as with the CBO, by the year a borrower started repayment). That also shows repayment dwindling over time and across cohorts. Their data concludes in 2013. Since then, the economy has improved significantly (up until 2020), yet repayment has only gotten worse.

The subject of the paper by Looney and Yannelis is delinquency and default, primarily by what those authors call nontraditional borrowers, meaning they attended postsecondary education later in life and/or attended for-profit institutions. The authors rightly attribute the influx of non-traditional borrowers into the student loan system as a consequence of the Great Recession and the generally-poor labor market options available to workers in its aftermath, especially those with no postsecondary qualification. The purpose of their paper is to propose IDR as a solution to that rise in delinquency, which it is. In their conclusion, the authors write:

Because of the ‘life cycle’ of borrowing, delinquencies and defaults are a lagging indicator, and the current [as of 2015] high rate of delinquency obscures some more favorable recent trends. In particular, the number of new borrowers at for-profit and two-year institutions has dropped substantially, due to the end of the recession and to increased oversight of the for-profit sector, which is likely to improve the risk characteristics of future repayment cohorts. Moreover, borrowing by first-year borrowers and other enrolled students has declined, both in the number of borrowers and the amounts borrowed. These factors, coupled with efforts by the Department of Education to expand and encourage the use of income-based repayment programs are likely to put downward pressure loan delinquency in the future, although with a lag.

This turned out to be an accurate prediction: delinquency has been in decline since that paper was released. But as we have shown, the result is rising balances and the crisis of non-repayment. The idea that deferring currently-due payments would make repayment easier when the labor market improved turned out not to be the case.

###### Figure 5.

We performed one final exercise to identify the effect of non-repayment, which is depicted in Figure 5. For each loan, we calculate the required annual payment amount (which is either the standard repayment schedule for a given initial balance and interest rate or an adjusted amount under IDR) as a share of the total outstanding balance, to see how the cost of carrying student loans has changed over time. Figure 5 plots two histograms for that number, one for all the loans in the cross-section data for 2009, the other for 2019. For reference, a standard 10-year uniform repayment plan would have that number in the neighborhood of 12-13% initially (i.e. when the total balance is highest, before progress toward repayment), depending on the interest rate. Over the life of a loan that is actually being repaid, the number increases since the required annual payment stays the same and the balance decreases. For that reason, as the distribution of outstanding loans gets older (recall Figure 3), we should expect to see the distribution of this annual-payment-to-outstanding-balance ratio shift to the right.

Instead, we see a much larger share of loans have required payments of zero or near-zero, which likely reflects the advent of IDR between 2009 and 2019. For loans in IDR, this number would decline over time, as the required annual payment amount is capped (conditional on income) and the balance is growing. There are also more significant mass points in the 2019 distribution around 7.5% and 12.5%, which may also reflect IDR required payment levels, although without income data it’s hard to be sure of that. Finally, there are, overall, higher payment ratios in the right half of the distribution, so the variance in the whole distribution has increased a good deal. That is probably for the same basic reason as we see rising variance in progress to repayment in Figure 1 and elsewhere in this analysis: as the federal student loan program has grown in size, more borrowers are coming from low-income and minority communities. As borrowers have diversified, more are in a worse position to repay and therefore suffer from rising balances over time.

### Conclusion

In light of rising student loan balances and their non-repayment, higher education policy analysts have tended to favor either expanding IDR and streamlining enrollment therein or limiting the reach of IDR and capping loan amounts, in the hope of re-directing students into less expensive institutions and into careers that will, ostensibly, enable them to repay their loans as scheduled. The effect of that is likely to be credit rationing: less advantaged students taking on more expensive private loans or not receiving higher education at all. The effect of expanding IDR is what we’ve already seen: balances mounting over time, with little or no progress toward repayment, even when the economy is as near to full employment as has been achieved in the United States in recent memory. Both of these alternative diagnoses decline to face reality head-on: we already have a great deal of student debt outstanding that isn’t being repaid and isn’t going to be repaid, and that debt resides disproportionately with minority borrowers victimized both by labor market credentialization and a lack of family wealth.

The implications are dire when it comes to household formation and asset accumulation over the life cycle, which is attenuated for millennials and will be for subsequent generations as well. It also likely inhibits marriage and reduces or delays child-bearing, labor market mobility, and entrepreneurship, not to mention retirement security for families who take on student debt on behalf of their children. The grand experiment in shifting the cost of higher education onto individual students and workers, at the same time as we closed off access to the labor market for anyone without postsecondary credentials, driving a broader and more diverse swathe of the population into the increasingly-expensive higher education system, has resulted in greater educational attainment, but not a better-paid workforce. Instead the debt is a lifetime drag on social mobility, widening wealth disparities between people whose families could pay for their education, or who needed less education in order to qualify themselves for professional careers, and those who had to finance it themselves and who need education to access opportunities that are rationed on the basis of race and class.

### Millennial Student Debt

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