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Now showing items 1-11 of 11

• #### Centrality dependence of pion freeze-out radii in Pb-Pb collisions at √sNN = 2.76 TeV

(Journal article; Peer reviewed, 2016)
We report on the measurement of freeze-out radii for pairs of identical-charge pions measured in Pb-Pb collisions at √sNN = 2.76 TeV as a function of collision centrality and the average transverse momentum of the pair kT. ...
• #### Centrality Dependence of the Charged-Particle Multiplicity Density at Midrapidity in Pb-Pb Collisions at √sNN =5.02 TeV

(Journal article; Peer reviewed, 2016)
The pseudorapidity density of charged particles, dNch/dη, at midrapidity in Pb-Pb collisions has been measured at a center-of-mass energy per nucleon pair of √sNN=5.02  TeV. For the 5% most central collisions, we measure ...
• #### Centrality dependence of the nuclear modification factor of charged pions, kaons, and protons in Pb-Pb collisions at √sNN =2.76 TeV

(Journal article; Peer reviewed, 2016)
Transverse momentum (pT) spectra of pions, kaons, and protons up to pT=20GeV/c have been measured in Pb-Pb collisions at √sNN=2.76TeV using the ALICE detector for six different centrality classes covering 0%–80%. The ...
• #### Event-shape engineering for inclusive spectra and elliptic flow in Pb-Pb collisions at √sNN =2.76 TeV

(Journal article; Peer reviewed, 2016)
We report on results obtained with the event-shape engineering technique applied to Pb-Pb collisions at √sNN=2.76 TeV. By selecting events in the same centrality interval, but with very different average flow, different ...
• #### Inclusive quarkonium production at forward rapidity in pp collisions at √s = 8 TeV

(Peer reviewed; Journal article, 2016)
• #### Measurement of an excess in the Yield of J/ψ at very low pT in Pb-Pb collisions at √sNN=2.76 TeV

(Journal article; Peer reviewed, 2016)
We report on the first measurement of an excess in the yield of J/ψ at very low transverse momentum (pT<0.3  GeV/c) in peripheral hadronic Pb-Pb collisions at √sNN=2.76  TeV, performed by ALICE at the CERN LHC. Remarkably, ...
• #### Measurement of Ds + production and nuclear modification factor in Pb-Pb collisions at √sNN = 2.76 TeV

(Journal article; Peer reviewed, 2016)
The production of prompt D s + mesons was measured for the first time in collisions of heavy nuclei with the ALICE detector at the LHC. The analysis was performed on a data sample of Pb-Pb collisions at a centre-of-mass ...
• #### Multipion Bose-Einstein correlations in pp,p -Pb, and Pb-Pb collisions at energies available at the CERN Large Hadron Collider

(Journal article; Peer reviewed, 2016)
Three- and four-pionBose-Einstein correlations are presented in pp, p-Pb, and Pb-Pb collisions at the LHC.We compare our measured four-pion correlations to the expectation derived from two- and three-pion measurements. ...
• #### Production of K∗(892)0 and ϕ (1020) in p–Pb collisions at √sNN = 5.02 TeV

(Journal article; Peer reviewed, 2016)
• #### Search for weakly decaying Λn and ΛΛ exotic bound states in central Pb-Pb collisions at √sNN=2.76 TeV

(Journal article; Peer reviewed, 2016)
• #### Study of cosmic ray events with high muon multiplicity using the ALICE detector at the CERN Large Hadron Collider

(Journal article; Peer reviewed, 2016)
ALICE is one of four large experiments at the CERN Large Hadron Collider near Geneva, specially designed to study particle production in ultra-relativistic heavy-ion collisions. Located 52 meters underground with 28 meters ...


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# Fight Finance

#### CoursesTagsRandomAllRecentScores

A company runs a number of slaughterhouses which supply hamburger meat to McDonalds. The company is afraid that live cattle prices will increase over the next year, even though there is widespread belief in the market that they will be stable. What can the company do to hedge against the risk of increasing live cattle prices? Which statement(s) are correct?

(i) buy call options on live cattle.

(ii) buy put options on live cattle.

(iii) sell call options on live cattle.

Select the most correct response:

Below are 4 option graphs. Note that the y-axis is payoff at maturity (T). What options do they depict? List them in the order that they are numbered.

You have just sold an 'in the money' 6 month European put option on the mining company BHP at an exercise price of $40 for a premium of$3.

Which of the following statements best describes your situation?

Below are 4 option graphs. Note that the y-axis is payoff at maturity (T). What options do they depict? List them in the order that they are numbered

You operate a cattle farm that supplies hamburger meat to the big fast food chains. You buy a lot of grain to feed your cattle, and you sell the fully grown cattle on the livestock market.

You're afraid of adverse movements in grain and livestock prices. What options should you buy to hedge your exposures in the grain and cattle livestock markets?

Select the most correct response:

Suppose that the US government recently announced that subsidies for fresh milk producers will be gradually phased out over the next year. Newspapers say that there are expectations of a 40% increase in the spot price of fresh milk over the next year.

Option prices on fresh milk trading on the Chicago Mercantile Exchange (CME) reflect expectations of this 40% increase in spot prices over the next year. Similarly to the rest of the market, you believe that prices will rise by 40% over the next year.

What option trades are likely to be profitable, or to be more specific, result in a positive Net Present Value (NPV)?

Assume that:

• Only the spot price is expected to increase and there is no change in expected volatility or other variables that affect option prices.
• No taxes, transaction costs, information asymmetry, bid-ask spreads or other market frictions.

All things remaining equal, according to the capital asset pricing model, if the systematic variance of an asset increases, its required return will increase and its price will decrease.
If the idiosyncratic variance of an asset increases, its price will be unchanged.

What is the relationship between the price of a call or put option and the total, systematic and idiosyncratic variance of the underlying asset that the option is based on? Select the most correct answer.

Call and put option prices increase when the:

The 'option price' in an option contract is paid at the start when the option contract is agreed to. or ?

The 'option strike price' in an option contract, also known as the exercise price, is paid at the start when the option contract is agreed to. or ?

Which one of the following is NOT usually considered an 'investable' asset for long-term wealth creation?

You believe that the price of a share will fall significantly very soon, but the rest of the market does not. The market thinks that the share price will remain the same. Assuming that your prediction will soon be true, which of the following trades is a bad idea? In other words, which trade will NOT make money or prevent losses?

Which option position has the possibility of unlimited potential losses?

In the Merton model of corporate debt, buying a levered company's debt is equivalent to buying risk free government bonds and:

In the Merton model of corporate debt, buying a levered company's shares is equivalent to:

In the Merton model of corporate debt, buying a levered company's debt is equivalent to buying the company's assets and:

Which of the following is the least useful method or model to calculate the value of a real option in a project?

A risky firm will last for one period only (t=0 to 1), then it will be liquidated. So it's assets will be sold and the debt holders and equity holders will be paid out in that order. The firm has the following quantities:

$V$ = Market value of assets.

$E$ = Market value of (levered) equity.

$D$ = Market value of zero coupon bonds.

$F_1$ = Total face value of zero coupon bonds which is promised to be paid in one year.

The levered equity graph above contains bold labels a to e. Which of the following statements about those labels is NOT correct?

A risky firm will last for one period only (t=0 to 1), then it will be liquidated. So it's assets will be sold and the debt holders and equity holders will be paid out in that order. The firm has the following quantities:

$V$ = Market value of assets.

$E$ = Market value of (levered) equity.

$D$ = Market value of zero coupon bonds.

$F_1$ = Total face value of zero coupon bonds which is promised to be paid in one year.

The risky corporate debt graph above contains bold labels a to e. Which of the following statements about those labels is NOT correct?

One of the reasons why firms may not begin projects with relatively small positive net present values (NPV's) is because they wish to maximise the value of their:

A moped is a bicycle with pedals and a little motor that can be switched on to assist the rider. Mopeds are useful for quick transport using the motor, and for physical exercise when using the pedals unassisted. This offers the rider:

You're thinking of starting a new cafe business, but you're not sure if it will be profitable.

You have to decide what type of cups, mugs and glasses you wish to buy. You can pay to have your cafe's name printed on them, or just buy the plain un-marked ones. For marketing reasons it's better to have the cafe name printed. But the plain un-marked cups, mugs and glasses maximise your:

Some financially minded people insist on a prenuptial agreement before committing to marry their partner. This agreement states how the couple's assets should be divided in case they divorce. Prenuptial agreements are designed to give the richer partner more of the couples' assets if they divorce, thus maximising the richer partner's:

An expansion option is best modeled as a or option?

An abandonment option is best modeled as a or option?

A timing option is best modeled as a or option?

According to option theory, it's rational for students to submit their assignments as or as possible?

The cheapest mobile phones available tend to be those that are 'locked' into a cell phone operator's network. Locked phones can not be used with other cell phone operators' networks.

Locked mobile phones are cheaper than unlocked phones because the locked-in network operator helps create a monopoly by:

Your firm's research scientists can begin an exciting new project at a cost of $10m now, after which there’s a: • 70% chance that cash flows will be$1m per year forever, starting in 5 years (t=5). This is the A state of the world.
• 20% chance that cash flows will be $3m per year forever, starting in 5 years (t=5). This is the B state of the world. • 10% chance of a major break through in which case the cash flows will be$20m per year forever starting in 5 years (t=5), or instead, the project can be expanded by investing another $10m (at t=5) which is expected to give cash flows of$60m per year forever, starting at year 9 (t=9). Note that the perpetual cash flows are either the $20m from year 4 onwards, or the$60m from year 9 onwards after the additional $10m year 5 investment, but not both. This is the C state of the world. The firm's cost of capital is 10% pa. What's the present value (at t=0) of the option to expand in year 5? A European call option will mature in $T$ years with a strike price of $K$ dollars. The underlying asset has a price of $S$ dollars. What is an expression for the payoff at maturity $(f_T)$ in dollars from owning (being long) the call option? A European put option will mature in $T$ years with a strike price of $K$ dollars. The underlying asset has a price of $S$ dollars. What is an expression for the payoff at maturity $(f_T)$ in dollars from owning (being long) the put option? A European call option will mature in $T$ years with a strike price of $K$ dollars. The underlying asset has a price of $S$ dollars. What is an expression for the payoff at maturity $(f_T)$ in dollars from having written (being short) the call option? A European put option will mature in $T$ years with a strike price of $K$ dollars. The underlying asset has a price of $S$ dollars. What is an expression for the payoff at maturity $(f_T)$ in dollars from having written (being short) the put option? Question 432 option, option intrinsic value, no explanation An American style call option with a strike price of $K$ dollars will mature in $T$ years. The underlying asset has a price of $S$ dollars. What is an expression for the current intrinsic value in dollars from owning (being long) the American style call option? Note that the intrinsic value of an option does not subtract the premium paid to buy the option. A risky firm will last for one period only (t=0 to 1), then it will be liquidated. So it's assets will be sold and the debt holders and equity holders will be paid out in that order. The firm has the following quantities: $V$ = Market value of assets. $E$ = Market value of (levered) equity. $D$ = Market value of zero coupon bonds. $F_1$ = Total face value of zero coupon bonds which is promised to be paid in one year. What is the payoff to equity holders at maturity, assuming that they keep their shares until maturity? A risky firm will last for one period only (t=0 to 1), then it will be liquidated. So it's assets will be sold and the debt holders and equity holders will be paid out in that order. The firm has the following quantities: $V$ = Market value of assets. $E$ = Market value of (levered) equity. $D$ = Market value of zero coupon bonds. $F_1$ = Total face value of zero coupon bonds which is promised to be paid in one year. What is the payoff to debt holders at maturity, assuming that they keep their debt until maturity? Will the price of a call option on equity or if the standard deviation of returns (risk) of the underlying shares becomes higher? Will the price of an out-of-the-money put option on equity or if the standard deviation of returns (risk) of the underlying shares becomes higher? Two call options are exactly the same, but one matures in one year and the other matures in two years. Which option would you expect to have the higher price, the option which matures or , or should they have the price? Two put options are exactly the same, but one matures in one year and the other matures in two years. Which option would you expect to have the higher price, the option which matures or , or should they have the price? Two call options are exactly the same, but one has a low and the other has a high exercise price. Which option would you expect to have the higher price, the option with the or exercise price, or should they have the price? Two put options are exactly the same, but one has a low and the other has a high exercise price. Which option would you expect to have the higher price, the option with the or exercise price, or should they have the price? Which of the following statements about European call options on non-dividend paying stocks is NOT correct? A man just sold a call option to his counterparty, a lady. The man has just now: Which one of the following statements about option contracts is NOT correct? Which of the following statements about option contracts is NOT correct? For every: If trader A has sold the right that allows counterparty B to buy the underlying asset from him at maturity if counterparty B wants then trader A is: After doing extensive fundamental analysis of a company, you believe that their shares are overpriced and will soon fall significantly. The market believes that there will be no such fall. Which of the following strategies is NOT a good idea, assuming that your prediction is true? Which of the below formulas gives the payoff $(f)$ at maturity $(T)$ from being long a call option? Let the underlying asset price at maturity be $S_T$ and the exercise price be $X_T$. Which of the below formulas gives the payoff $(f)$ at maturity $(T)$ from being short a call option? Let the underlying asset price at maturity be $S_T$ and the exercise price be $X_T$. Which of the below formulas gives the payoff $(f)$ at maturity $(T)$ from being long a put option? Let the underlying asset price at maturity be $S_T$ and the exercise price be $X_T$. Which of the below formulas gives the payoff $(f)$ at maturity $(T)$ from being short a put option? Let the underlying asset price at maturity be $S_T$ and the exercise price be $X_T$. Which one of the below option and futures contracts gives the possibility of potentially unlimited gains? A trader buys one crude oil European style call option contract on the CME expiring in one year with an exercise price of$44 per barrel for a price of $6.64. The crude oil spot price is$40.33. If the trader doesn’t close out her contract before maturity, then at maturity she will have the:

Which of the below formulas gives the profit $(\pi)$ from being long a call option? Let the underlying asset price at maturity be $S_T$, the exercise price be $X_T$ and the option price be $f_{LC,0}$. Note that $S_T$, $X_T$ and $f_{LC,0}$ are all positive numbers.

Which of the below formulas gives the profit $(\pi)$ from being short a call option? Let the underlying asset price at maturity be $S_T$, the exercise price be $X_T$ and the option price be $f_{LC,0}$. Note that $S_T$, $X_T$ and $f_{LC,0}$ are all positive numbers.

Which of the below formulas gives the profit $(\pi)$ from being long a put option? Let the underlying asset price at maturity be $S_T$, the exercise price be $X_T$ and the option price be $f_{LP,0}$. Note that $S_T$, $X_T$ and $f_{LP,0}$ are all positive numbers.

Which of the below formulas gives the profit $(\pi)$ from being short a put option? Let the underlying asset price at maturity be $S_T$, the exercise price be $X_T$ and the option price be $f_{LP,0}$. Note that $S_T$, $X_T$ and $f_{LP,0}$ are all positive numbers.

A trader sells one crude oil European style call option contract on the CME expiring in one year with an exercise price of $44 per barrel for a price of$6.64. The crude oil spot price is $40.33. If the trader doesn’t close out her contract before maturity, then at maturity she will have the: A trader buys one crude oil European style put option contract on the CME expiring in one year with an exercise price of$44 per barrel for a price of $6.64. The crude oil spot price is$40.33. If the trader doesn’t close out her contract before maturity, then at maturity she will have the:

Which of the following statements about call options is NOT correct?

A trader just bought a European style put option on CBA stock. The current option premium is $2, the exercise price is$75, the option matures in one year and the spot CBA stock price is $74. Which of the following statements is NOT correct? A bank buys 1000 European put options on a$10 non-dividend paying stock at a strike of $12. The bank wishes to hedge this exposure. The bank can trade the underlying stocks and European call options with a strike price of 7 on the same stock with the same maturity. Details of the call and put options are given in the table below. Each call and put option is on a single stock.  European Options on a Non-dividend Paying Stock Description Symbol Put Values Call Values Spot price ($) $S_0$ 10 10 Strike price ($) $K_T$ 12 7 Risk free cont. comp. rate (pa) $r$ 0.05 0.05 Standard deviation of the stock's cont. comp. returns (pa) $\sigma$ 0.4 0.4 Option maturity (years) $T$ 1 1 Option price ($) $p_0$ or $c_0$ 2.495350486 3.601466138 $N[d_1]$ $\partial c/\partial S$ 0.888138405 $N[d_2]$ $N[d_2]$ 0.792946442 $-N[-d_1]$ $\partial p/\partial S$ -0.552034778 $N[-d_2]$ $N[-d_2]$ 0.207053558 Gamma $\Gamma = \partial^2 c/\partial S^2$ or $\partial^2 p/\partial S^2$ 0.098885989 0.047577422 Theta $\Theta = \partial c/\partial T$ or $\partial p/\partial T$ 0.348152078 0.672379961

Which of the following statements is NOT correct?

Which of the following quantities from the Black-Scholes-Merton option pricing formula gives the Delta of a European call option?

Where:

$$d_1=\dfrac{\ln[S_0/K]+(r+\sigma^2/2).T)}{\sigma.\sqrt{T}}$$ $$d_2=d_1-\sigma.\sqrt{T}=\dfrac{\ln[S_0/K]+(r-\sigma^2/2).T)}{\sigma.\sqrt{T}}$$

Which of the following quantities from the Black-Scholes-Merton option pricing formula gives the Delta of a European put option?

Which of the following quantities from the Black-Scholes-Merton option pricing formula gives the risk-neutral probability that a European call option will be exercised?

Which of the following quantities from the Black-Scholes-Merton option pricing formula gives the risk-neutral probability that a European put option will be exercised?

Which derivatives position has the possibility of unlimited potential gains?

Which of the following terms about options are NOT synonyms?

What derivative position are you exposed to if you have the obligation to sell the underlying asset at maturity, so you will definitely be forced to sell the underlying asset?

You just paid $4 for a 3 month European style call option on a stock currently priced at$47 with a strike price of $50. The stock’s next dividend will be$1 in 4 months’ time. Note that the dividend is paid after the option matures. Which of the below statements is NOT correct?

When does a European option's last-traded market price become a sunk cost?

A European call option should only be exercised if:

A put option written on a risky non-dividend paying stock will mature in one month. As is normal, assume that the option's exercise price is non-zero and positive $(K>0)$ and the stock has limited liability $(S>0)$.

Which of the following statements is NOT correct? The put option's:

Below are some statements about futures and European-style options on non-dividend paying stocks. Assume that the risk free rate is always positive. Which of these statements is NOT correct? All other things remaining equal:

Below are some statements about European-style options on non-dividend paying stocks. Assume that the risk free rate is always positive. Which of these statements is NOT correct?

Question 831  option, American option, no explanation

Which of the following statements about American-style options is NOT correct? American-style:

A 12 month European-style call option with a strike price of $11 is written on a dividend paying stock currently trading at$10. The dividend is paid annually and the next dividend is expected to be $0.40, paid in 9 months. The risk-free interest rate is 5% pa continuously compounded and the standard deviation of the stock’s continuously compounded returns is 30 percentage points pa. The stock's continuously compounded returns are normally distributed. Using the Black-Scholes-Merton option valuation model, determine which of the following statements is NOT correct. Which of the following statements about an option (either a call or put) and its underlying stock is NOT correct? Which of the following statements about an option (either a call or put) and its underlying stock is NOT correct?  European Call Option on a non-dividend paying stock Description Symbol Quantity Spot price ($) $S_0$ 20 Strike price ($) $K_T$ 18 Risk free cont. comp. rate (pa) $r$ 0.05 Standard deviation of the stock's cont. comp. returns (pa) $\sigma$ 0.3 Option maturity (years) $T$ 1 Call option price ($) $c_0$ 3.939488 Delta $\Delta = N[d_1]$ 0.747891 $N[d_2]$ $N[d_2]$ 0.643514 Gamma $\Gamma$ 0.053199 Theta ($/year) $\Theta = \partial c / \partial T$ 1.566433 Being long a call and short a put which have the same exercise prices and underlying stock is equivalent to being: A stock, a call, a put and a bond are available to trade. The call and put options' underlying asset is the stock they and have the same strike prices, $K_T$. Being long the call and short the stock is equivalent to being: A stock, a call, a put and a bond are available to trade. The call and put options' underlying asset is the stock they and have the same strike prices, $K_T$. You are currently long the stock. You want to hedge your long stock position without actually trading the stock. How would you do this? A one year European-style call option has a strike price of$4. The option's underlying stock pays no dividends and currently trades at $5. The risk-free interest rate is 10% pa continuously compounded. Use a single step binomial tree to calculate the option price, assuming that the price could rise to$8 $(u = 1.6)$ or fall to $3.125 $(d = 1/1.6)$ in one year. The call option price now is: A one year European-style put option has a strike price of$4. The option's underlying stock pays no dividends and currently trades at $5. The risk-free interest rate is 10% pa continuously compounded. Use a single step binomial tree to calculate the option price, assuming that the price could rise to$8 $(u = 1.6)$ or fall to $3.125 $(d = 1/1.6)$ in one year. The put option price now is: A one year European-style call option has a strike price of$4.

The option's underlying stock currently trades at $5, pays no dividends and its standard deviation of continuously compounded returns is 47% pa. The risk-free interest rate is 10% pa continuously compounded. Use the Black-Scholes-Merton formula to calculate the option price. The call option price now is: A one year European-style put option has a strike price of$4.

The option's underlying stock currently trades at $5, pays no dividends and its standard deviation of continuously compounded returns is 47% pa. The risk-free interest rate is 10% pa continuously compounded. Use the Black-Scholes-Merton formula to calculate the option price. The put option price now is: Question 903 option, Black-Scholes-Merton option pricing, option on stock index A six month European-style call option on the S&P500 stock index has a strike price of 2800 points. The underlying S&P500 stock index currently trades at 2700 points, has a continuously compounded dividend yield of 2% pa and a standard deviation of continuously compounded returns of 25% pa. The risk-free interest rate is 5% pa continuously compounded. Use the Black-Scholes-Merton formula to calculate the option price. The call option price now is: Question 904 option, Black-Scholes-Merton option pricing, option on future on stock index A six month European-style call option on six month S&P500 index futures has a strike price of 2800 points. The six month futures price on the S&P500 index is currently at 2740.805274 points. The futures underlie the call option. The S&P500 stock index currently trades at 2700 points. The stock index underlies the futures. The stock index's standard deviation of continuously compounded returns is 25% pa. The risk-free interest rate is 5% pa continuously compounded. Use the Black-Scholes-Merton formula to calculate the option price. The call option price now is: A non-dividend paying stock has a current price of$20.

The risk free rate is 5% pa given as a continuously compounded rate.

Options on the stock are currently priced at $5 for calls and$5.55 for puts where both options have a 2 year maturity and an exercise price of $24. You suspect that the call option contract is mis-priced and would like to conduct a risk-free arbitrage that requires zero capital. Which of the following steps about arbitraging the situation is NOT correct? If a call option is in-the-money, then the spot price ($S_0$) is than, than or to the call option's strike price ($K_T$)? If a put option is in-the-money, then the spot price ($S_0$) is than, than or to the put option's strike price ($K_T$)? If a call option is out-of-the-money, then the spot price ($S_0$) is than, than or to the call option's strike price ($K_T$)? Question 954 option, at the money option If a put option is at-the-money, then the spot price ($S_0$) is than, than or to the put option's strike price ($K_T$)? If a put option is out-of-the-money, then the spot price ($S_0$) is than, than or to the put option's strike price ($K_T$)? A bank sells a European call option on a non-dividend paying stock and delta hedges on a daily basis. Below is the result of their hedging, with columns representing consecutive days. Assume that there are 365 days per year and interest is paid daily in arrears.  Delta Hedging a Short Call using Stocks and Debt Description Symbol Days to maturity (T in days) 60 59 58 57 56 55 Spot price ($) S 10000 10125 9800 9675 10000 10000 Strike price ($) K 10000 10000 10000 10000 10000 10000 Risk free cont. comp. rate (pa) r 0.05 0.05 0.05 0.05 0.05 0.05 Standard deviation of the stock's cont. comp. returns (pa) σ 0.4 0.4 0.4 0.4 0.4 0.4 Option maturity (years) T 0.164384 0.161644 0.158904 0.156164 0.153425 0.150685 Delta N[d1] = dc/dS 0.552416 0.582351 0.501138 0.467885 0.550649 0.550197 Probability that S > K at maturity in risk neutral world N[d2] 0.487871 0.51878 0.437781 0.405685 0.488282 0.488387 Call option price ($) c 685.391158 750.26411 567.990995 501.487157 660.982878 ? Stock investment value ($) N[d1]*S 5524.164129 5896.301781 4911.152036 4526.788065 5506.488143 ? Borrowing which partly funds stock investment ($) N[d2]*K/e^(r*T) 4838.772971 5146.037671 4343.161041 4025.300909 4845.505265 ? Interest expense from borrowing paid in arrears ($) r*N[d2]*K/e^(r*T) 0.662891 0.704985 0.594994 0.551449 ? Gain on stock ($) N[d1]*(SNew - SOld) 69.052052 -189.264008 -62.642245 152.062648 ? Gain on short call option ($) -1*(cNew - cOld) -64.872952 182.273114 66.503839 -159.495721 ? Net gain ($) Gains - InterestExpense 3.516209 -7.695878 3.266599 -7.984522 ? Gamma Γ = d^2c/dS^2 0.000244 0.00024 0.000255 0.00026 0.000253 0.000255 Theta θ = dc/dT 2196.873429 2227.881353 2182.174706 2151.539751 2266.589184 2285.1895

In the last column when there are 55 days left to maturity there are missing values. Which of the following statements about those missing values is NOT correct?

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# What is the cumulative hazard function?

## What is the cumulative hazard function?

Cumulative hazard is integrating (instantaneous) hazard rate over ages/time. Hazard rate is conditional on not having experienced the event before t, so for a population it may sum over 1. You may look up some human mortality life table, although this is a discrete time formulation, and try to accumulate mx.

### How do you find the cumulative hazard function?

The cumulative hazard for the Weibull distribution is H(t) = (t/\alpha)^\gamma, so a plot of y versus x on a log-log scale should resemble a straight line with slope \gamma if the Weibull model is appropriate.

#### What is survival hazard function?

The hazard function (also called the force of mortality, instantaneous failure rate, instantaneous death rate, or age-specific failure rate) is a way to model data distribution in survival analysis. The function is defined as the instantaneous risk that the event of interest happens, within a very narrow time frame.

How do you read a hazard function plot?

These patterns can be interpreted as follows.

1. Decreasing: Items are less likely to fail as they age. A decreasing hazard indicates that failure typically happens in the early period of a product’s life.
2. Constant: Items fail at a constant rate.
3. Increasing: Items are more likely to fail as they age.

What is Cox regression used for?

Cox regression (or proportional hazards regression) is method for investigating the effect of several variables upon the time a specified event takes to happen. In the context of an outcome such as death this is known as Cox regression for survival analysis.

## What is Cox hazard ratio?

Cox proportional hazards model and hazard ratio. The Cox model, a regression method for survival data, provides an estimate of the hazard ratio and its confidence interval. The hazard ratio is an estimate of the ratio of the hazard rate in the treated versus the control group.

### How do you calculate hazard function?

λ(t)=f(t)S(t), which some authors give as a definition of the hazard function. In words, the rate of occurrence of the event at duration t equals the density of events at t, divided by the probability of surviving to that duration without experiencing the event.

#### How do you calculate cumulative hazard in R?

The cummulative hazard is commonly used to estimate the hazard probability. It’s defined as H(t)=−log(survivalfunction)=−log(S(t)). The cumulative hazard (H(t)) can be interpreted as the cumulative force of mortality.

Is survival function the same as hazard function?

Because of the given sign here, the hazard function is sometimes called a conditional failure rate. Note that, in contrast to the survival function, which focuses on not failing, the hazard function focuses on failing, that is, on the event occurring.

What is survival function in statistics?

The survival function is a function that gives the probability that a patient, device, or other object of interest will survive beyond any specified time. The survival function is also known as the survivor function or reliability function.

## How do you read hazard rates?

Interpretation of the Hazard Ratio A hazard ratio of 1 implies equal hazard in the two groups; if the hazard ratio is less than 1, it would mean that the hazard was less in persons with this putative risk factor—that its presence was protective.

### Which is the best description of the Gompertz function?

It is a sigmoid function which describes growth as being slowest at the start and end of a given time period. The right-hand or future value asymptote of the function is approached much more gradually by the curve than the left-hand or lower valued asymptote.

#### When is the hazard function greater than 1?

When is greater than 1, the hazard function is concave and increasing. When it is less than one, the hazard function is convex and decreasing. t h(t) Gamma. > 1 = 1 < 1 Weibull Distribution: The Weibull distribution can also be viewed as a generalization of the expo- nential distribution, and is denoted W(p;).

Is the Gompertz-Makeham survival distribution accurate?

This model is both logical and reasonably accurate. The Gompertz-Makeham survival distribution starts with the assumption that “instantaneous risk of death” has two components: 1) a constant term that everyone is susceptible to, and 2) a term that increases exponentially over time.

Which is the model that modifies the Gompertz law?

Such a modeling framework can be also widely called the nonlinear mixed-effects model or hierarchical nonlinear model. Based on the above considerations, Wheldon proposed a mathematical model of tumor growth, called the Gomp-Ex model, that slightly modifies the Gompertz law.


text:
Communicating astronomy with the public: perspectives of an international community of practice

Abstract:

Communities of practice in science communication can make important contributions to public engagement with science but are under-researched. In this article, we look at the perspectives of a community of practice in astronomy communication regarding (relations with) their public(s). Most participants in this study consider that public(s) have several deficits and vulnerabilities. Moreover, practitioners have little to no contact with (and therefore make no use of) academic research on science communication. We argue that collaboration between science communication researchers and practitioners could benefit the science-public relationship and that communities of practice may be critical to that purpose.

Keywords:

12 November 2020

19 February 2021

10 May 2021

1 Context

Science and Technology (S&T) are at the core of contemporary culture, welfare and democracy. S&T are expected to increase economic growth and improve people’s lives in many ways, and shape citizens’ identities and thinking regarding societal issues such as climate change, energy, food security and health [National Academies of Sciences, Engineering, and Medicine et al., 2016; Davies and Horst, 2016].

Such expectations put the relations between the scientific community and (the rest of) society under the spotlight and increase the importance of individuals and organizations working as facilitators (or translators) of science. This is not an easy task. The complex environment of modern societies — where different specializations, cultures, languages and modes of meaning-making coexist — adds to the challenges of developing science communication practices that may serve multiple publics and their diverse needs.

Science communicators “move knowledge around” [Meyer, 2010, p. 118], and also create new forms of knowledge [Meyer, 2010]. As key actors in the establishment of connections “between science and society at large, making elements of the science domain approachable, understandable and eventually appealing” [Bucchi and Trench, 2014, p. 2], they are essential to implement activities towards public engagement with science at various levels and may even operationalize science policies driven by political agendas [Weingart and Joubert, 2019].

In order to foster connections and mutual understanding between research communities and other sectors of society, science communicators aim to develop a “common language” in their practice [Meyer, 2010; Stocklmayer, Gore and Bryant, 2001]. Practitioners of science communication may simultaneously be members of multiple professional groups and take up different roles, such as scientists, informal science educators, press officers, science journalists, bloggers, and others. It is often the case that science communicators organize themselves into networks of knowledge and experience sharing, i.e. into communities of practice. These are composed of (groups of) individuals that gather around a common goal: the wish to improve communication practices brings the community together. Practitioners act within their community of practice according to their institutional role and develop various forms of interaction thereby aligning perspectives and facilitating transactions among multiple stakeholders [Kuhn, 2002; Meyer, 2010; Wenger and Wenger-Trayner, 2015].

Several studies have focused on scientists’ participation in science communication [e.g. Bauer and Jensen, 2011; Besley and Nisbet, 2013; Entradas and Bauer, 2019; Wellcome Trust, 2001]; however, research that focuses primarily on practitioners’ perceptions, and especially on the roles of this community of practice, is scarce. Hence, the contribution of these specific social groups and structures to the science-society relationship has been overlooked.

Aside from this research gap, there seems to be a certain distance between the practice of science communication and the corresponding academic research [Miller, 2008; Riesch, Potter and Davies, 2016]. On the one hand, the normative ways in which public understanding of science (PUS) research often addresses science communication matters neglect the body of reflections and knowledge that practitioners develop in their practice; on the other hand, that research is seen as of little use for practitioners1 [Riesch, Potter and Davies, 2016]. Although science communication practitioners and academics are distinct communities, narrowing the relationship between research and practice in science communication is a continuously important goal [Seethaler et al., 2019]. In fact, there is evidence that when this kind of collaboration between research and practice on science communication occurs, multiple benefits are achieved, as reported by Riedlinger et al. [2019] with regard to storytelling for engaging with the public. Such collaboration can “also produce generalisable findings and contribute to theory building in the science communication field” [p. 10]. Therefore, furthering dialogues between science communication research and practice [Jensen and Gerber, 2020], bringing practitioners’ experiences to peer-reviewed literature,2 and linking empirical scholarship to practice are expected to promote mutual gains, and unleash diverse opportunities for improvement concerning a variety of topics and methods for communicating science. This kind of cooperation may be particularly encouraged within communities of practice, which typically gather multiple groups of people around common interests and experiment different approaches. Moreover, communities of practice may use and spread academic research contributing to bridge the scholarship-practice divide.

In line with the points that we are making, the systematic review of science communication research conducted by Gerber et al. [2020] identified the lack of knowledge transfer between theory and practice as a challenge for the area. They also found a gap concerning research on science communication practitioners themselves. This article offers contributions to start filling these gaps.

2 Objectives

This study analyses the perceptions and practices of a specific community in science communication, namely the astronomy communication community, which is briefly characterized in the next paragraph.

The International Astronomical Union (IAU) was founded in 1919 “to promote and safeguard the science of astronomy in all its aspects, including research, communication, education and development, through international cooperation”.3 To pursue its objectives, the IAU created several Divisions (D), Commissions (C) and Working Groups (WG). Among them, we find the Commission C2 — Communicating Astronomy with the Public,4 which brings together a worldwide group of individuals working on public communication of astronomy. The Commission functions as a hub for members with the common interest of communicating astronomy to the public, and provides opportunities for the community to share resources and best practices via several platforms, such as the practitioner journal Communicating Astronomy with the Public (CAP)5 and the biannual CAP conference. Described as a “think/do tank that convenes the astronomy communication community, and seeds initiatives to explore new ways to communicate astronomy with the public”, the conference is a privileged encounter of the astronomy communicators’ community of practice aiming to “endorse standards, best practices and requirements for public communication”.6 The 2018 CAP conference took place in Fukuoka, Japan, and had 446 participants from 53 countries. The gathering provided an opportunity to study practitioners’ perceptions about public engagement with astronomy and interconnections of science communication research and practice.

We explore the following questions:

1. How do astronomy communication practitioners conceive their public(s) and which impacts do they expect to have?
2. What kind of public engagement do practitioners seek and how is that embedded in their interventions?
3. How do they appropriate science communication research in their practices?

This work results from the authors’ multiple lenses: on the one hand, as elements of the community of practice in astronomy communication (the two first authors) and, on the other hand, as researchers in the field of science communication. Supported by diverse methods of data collection, we conducted an exploratory analysis of the community’s perspectives, as detailed below.

3 Methodology

A key starting point for this study is the assumption that social subjects’ interpretations and the meanings that they ascribe to reality are essential to inform social research.

In looking at community practices, we used a participant observation approach, which focus on meanings as seen from the standpoint of insiders [Flick, 2004; Hammersley, 2015]. In order to acquire detailed insights into participants’ experiences and perspectives, we conducted a set of semi-structured interviews [Jensen and Laurie, 2016]. In addition, we used other data sources, namely document analysis (of certain aspects of the conference proceedings book) and a field diary. These methods allowed us to complement the information offered in the interviews, showing us how practices really work [Flick, 2004].

The question of representativeness was present in our multiple discussions of the study: can we present findings in terms of the community or can we only speak of the perceptions of some of its members? Although we acknowledge that communities of practice are varied and formed by individuals with different profiles, we realized that certain ideas and perspectives kept appearing recurrently in the interviews. As we neared ‘meaning saturation’, we considered that more interviews would not have changed our findings substantively. Observation of conference presentations, informal conversations and other forms of interaction of community members further contributed to identifying shared views. What we offer below is thus the result of multiple methods for collecting and analysing data that led to an interpretative and critical analysis of practices and meanings. We focus on what appears to be most common within the astronomy communication community, although care should be exercised in appraising this analysis to avoid over-generalizations. Science communication is always situated, and is motivated by diverse reasons and purposes [Aikenhead, 2001; Canfield et al., 2020; Entradas, 2016], which requires looking at the specific contexts where it happens.

We selected 16 interviewees ($N=16$; 5 female, 11 male) during the conference, including practitioners from different countries, at different career stages and, working with different audiences (see Table 1). Most interviewees ($N=12$) held a university degree in the field of Physics or Astronomy, and four reported having some advanced training in informal science education or science communication. For the selection of respondents, 10 community active members were initially identified. To this end, we took the following factors into account: participation in previous editions of the CAP; membership of the C2 committee and other IAU groups of interest to the community (such as the WG Astronomy for Equity and Inclusion, the WG Astronomy Educational Resources — AstroEDU, the Office of Astronomy for Outreach, and the Office of Astronomy for Development); and/or involvement as members of the 2018 conference organizing committee. The remaining interviewees were suggested as interviews progressed and were selected considering their age, career stage, function, geographical location, and the type of audience to which they address their practices. A strong presence of interviewees from Asia reflected the distribution of conference participants: 277 came from Asia, of which 200 came from Japan, the conference venue. The interviews were anonymous in order to reduce possible restrictions on responses, associated with constraints related to name, institution, function or position as astronomy communicators.

Table 1: Respondents profiles and audiences.

Despite the practitioners’ identification of several publics, it was possible to realize that more than half developed their main activity, directly or indirectly, in formal and informal educational settings (with pre-University students, teachers and educators). Four interviewees spoke of the media as a significant audience. It should also be noted that two individuals worked in the tourism sector (where there has been a growth in the offer of experiences of astronomical observation).

Table 2 presents our research goals regarding the interviews in connection with the interview script. The script was adjusted while conducting the interviews with the various participants to acknowledge their spontaneous references to some themes and to enhance the depth of responses (for instance, by asking for specific examples or drawing on something that was said and asking for elaboration). Interviews ranged from 15 to 50 minutes and were audio-recorded after verbal permission. Further to transcription, we analysed the data assisted by RQDA software [Huang, 2014]. We then constructed 33 codes, which after additional investigation led to three main themes: the public; the community’s concerns regarding public engagement; and practices for engagement (see Table 2).

Table 2: Goals, questions, and themes regarding the interviews.

We also considered the field diary notes collected throughout the conference (concerning observations at workshops, and parallel and poster sessions) with the aim of searching for common goals, methodologies, and narratives among the community.

Finally, we analysed the conference proceedings book and looked for references to academic publications on science communication with the goal of understanding how that knowledge may be considered and appropriated by astronomy communicators.

4 Findings

In this section, we present findings associated with the main themes found in the interviews, complemented with insights from observation of practices and with analysis of the CAP proceedings book. Regardless of the diversity of respondents and conference participants (the community is geographically spread, targets different audiences and communicates on behalf of different stakeholders), we found several common views and practices across the community.

4.1 Views on the public

Understandings of the public(s) of science communication are vitally important to practice. Below we discuss several traits that emerged from our interviewees.

The public is emotionally connected to astronomy. Practitioners consider that the public values the science of astronomy in seeking answers to their questions and appreciate those who can elucidate them. Astronomy, they claim, offers “magestical” pictures (namely from NASA and ESO) and addresses the big questions (“Where do we come from? Where are we going? What will happen to our home, the Earth? What is our place in the universe? Are we alone?” [E6]). Besides, there is some “magic and romance” in the stars and planets (“we wish upon a star” [E9]), contributing for people to have an affective liaison to the subject. The public is, therefore, portraited as emotionally connected to astronomy, which can be a powerful hook to trigger interest for science in general, especially STEM (Science, Technology, Engineering and Mathematics) subject areas.

The public lacks knowledge and has several misconceptions and stereotypes about science and scientists. Most interviewees ($N=13$) mentioned that the public lacks knowledge of science and the scientific process and holds several misconceptions, which are particularly damaging in face of various forms of pseudoscience. For astronomy communicators, the confusion between astronomy and astrology is a much-referenced example. In this respect, the lack of scientific literacy to distinguish science from pseudoscience is seen as critical [Allum, 2011; Stocklmayer, Gore and Bryant, 2001].

According to interviewees ($N=11$), the public associates several stereotypes with science and scientists: “science is difficult”, “[it is] only for special people” [E16]. Some referred to concrete actions to combat stereotypes, such as gender-related ones: “I always try to use examples of the female astronomers in my talks” [E13]. The mentioned barriers for access to science also included racial, ethnic, disability or socio-economic conditions. In contrast, interviewees emphasized that astronomy is inclusive and suited to all, as it addresses fundamental questions that concern the whole of humanity: “Astronomy is a science that can be reached by everyone through inclusion, through diversity, through equity policies, through empathy” [E6]. In fact, the idea that astronomy brings improvements to society (“the importance of astronomy for the betterment of society” [E6]) is a recurrent assumption in the speech of community members, who seem personally committed to its promotion.

The public may influence science policies. Several interviewees ($N=7$) recognized that public support is essential to influence science policies, especially science funding. Science policies and the role of governments and scientific organizations were highlighted as crucial aspects of the science-society relationship. Policies were prized either by potentially promoting equal access amongst several groups (considering gender, ethnicity, race, disabilities), by promoting proximity and free access to science, or by levering the economy through investments on science infrastructures.

Although astronomy communicators saw the public as very important in relation to science policies, we found no considerations in the interviews that would lead us to think that, in their opinion, the public should be a participant in the governance of science. This was not even the case in the speech of practitioners based in Europe where there is a substantial investment in relevant programs, such as the European Union’s framework programme Horizon 2020 Science With and For Society (Swafs),7 which is based on democratic ideals. Communication practitioners tend to assume that people have the right to know where their money and taxes are being spent, and to know what are the products and applications for society of the investment in science, but this is how far views on science governance and democratization go. Public engagement understood as participation in policy seems to remain confined to abstract discourses in politics and academia, with the astronomy communication community paying little attention — and assigning only a limited role — to the public in policymaking [Entradas, 2016].

4.2 Practices for public engagement

Astronomy communicators see themselves as facilitators between science and the public, with the tools and methodologies to bring science to the public being planned in a way that matches people’s interests and expectations. The community appears to respond to the public’s perceived emotional connection to astronomy by using emotional content (namely scientific storytelling), and by promoting empathy towards science and scientists (scientists are “just humans” [E7]). They also emphasized the relevance of astronomy in people’s daily life and in society, and how it may help solve societal issues.

In order to change the public’s attitude towards science, communicators point them to “reliable sources” about the science of astronomy and the processes involved in knowledge-building in order to build a “scientific mind” and “critical thinking” [E3]. Communicators described a diverse range of actions, both in form and content, but the predominant model of communication with the public rests on the idea of “transmission” of information about science and scientists (“this is the message I have to transmit” [E7]; “that will make sure that the message gets across” [E13]). This prevailing traditional view, based on the transmission model, according to the theory of communication [e.g. McQuail, 1998], indicates the continuing dominance of a one-way communication model for enhancement of scientific literacy [Bauer, 2009; Pardo and Calvo, 2004].

Nevertheless, we found clues in practitioners’ speech to spaces for quasi-dialogue and discussion about science subjects. The perception that the public enjoys to converse about and discuss science, and knowing the daily life of a scientist and science institution, shows that the public seeks a relationship of trust, closeness and transparency (“the public is very interested in what we do” [E7]). Closer proximity to scientists and scientific institutions are associated with a positive attitude by the public. Although not clear about the terms in which dialogue may occur, interviewees seemed to suggest that it is mostly related to knowledge of facts and processes of science, and to returns on investment in science and finance:

everything nowadays has to have an economic value, […] every time you talk about astronomy then you have one person in the group asking: ‘— yeah but what is the output, what can we sell out of astronomy?’” [E7].

Although interviewees employed the term “engagement” several times, it seemed to refer to people’s involvement with science in a cognitive, behavioural or emotional sense (aspects that tend to be foregrounded in education research) and not so much in the sense of participation and governance of science (more commonly discussed in the field of science communication research) [e.g. Lewenstein, 2015].

The astronomy communication community seems to conceive this cognitive and emotional engagement as the first step for science literacy. In their responses to our questions, practitioners offered clues to multiple goals for engaging the public with astronomy, namely:

• to increase interest in and awareness of science;
• to talk about the process of scientific knowledge construction;
• to make people aware of the practices and constraints of science and scientists;
• to demonstrate the applications of science in the practical life of citizens (Global Positioning System (GPS), charge-coupled device (CCD), etc.);
• to make connections between astronomy and other areas of knowledge and entertainment (STEM, History, Music, Art);
• to talk about astronomy’s contributions to solve societal problems (global warming, waste, energy, health);
• to help develop critical thinking for assessing the trustworthiness of scientific claims (mainly in the media).

All these aspects support the construction of critical science literacy [Carvalho, 2004; Priest, 2013], which accounts for broad questions related to the production of scientific research and its links to several contexts of people’s lives.

Despite interviewees referring to motives for concern related to the education and media arenas, we found that the astronomy communication community aspires to have education and media agents as allies in promoting interest in science and helping address several of their priorities.

4.3 Major concerns on engagement

Interviewees pointed to various types of concerns relevant to their public engagement practices. They mainly concern science at school, STEM careers, the gender gap, and the media.

Interviewees corroborated the idea that students’ dislike for science at school is one of the reasons for low rates in academic and professional careers linked to science [DeWitt, Osborne et al., 2013] and aimed for attitude change. They consider that they can play a part by providing resources and fun activities:

at school, I think kids tend to say they don’t like science or they hate math”; “once they get out of the school and come to our science centre and they have lots of fun things, they usually enjoy science” [E14].

Another concern is the gender gap on STEM subjects, and how astronomy may contribute positively [e.g. Sjøberg and Schreiner, 2010]. Some studies [e.g. DeWitt and Bultitude, 2020; Lane, Goh and Driver-Linn, 2012] have pointed out that the link between science, power and male roles can be an obstacle to some disadvantaged groups, including women, indigenous and African-descent communities, which some of the practitioners interviewed in our research also mentioned. This raises questions about the ways in which science literacy has been problematized to contribute to attitude change among these specific social groups and how communities of practice are addressing this concern. Although the astronomy communication community seemed open and alert to this kind of issues, members showed some uncertainty on how to direct their practices. One interviewee suggested looking into social sciences research on matters such as gender balance and inclusion: “[we have] a specific section on diversity and inclusion in a more formal research on social sciences” [E6].

The media also seem to represent a concern to this community. Despite being seen as essential to disseminate scientific information and to raise public interest in science, interviewees consider that the media reinforce existing stereotypes and misconceptions related to science and scientists, and that media professionals do not always bother to convey the correct information by checking sources:

some people view, — and sometimes the media views — scientists like geniuses” [E14];

usually I write [a news story] myself, and I give it for the media, [or else] […] there is a wrong interpretation and so I don’t want to have that” [E1].

They attribute an important role to the media in shaping opinions about science and scientists (“the media has a very important role because they are also the ones who define people right now” [E3]). However, interviewees affirm that there is a barrier between the media and the scientific community, a mutual misunderstanding and mistrust, which some academic studies also demonstrate [e.g. Besley and Nisbet, 2013; Peters et al., 2008]. Suspicion is stronger concerning new media in online platforms than the traditional press, which frequently has (or used to have) specialized science journalists:

we have the reporter or journalist for print media, they have their rules, and they stick to the rules up until now. I know them, I can say that because I know them, I work with them, the problem is in online media” [E3].

We noticed an attempt to work with the media, so that media professionals may have a better understanding of science, scientific facts, science processes and scientists. However, once again, the vast majority of interviewees refer to the media and the communication process in a simplistic, linear, sender/receiver-type model (“the information that they [the media] are going to transmit” [E1]). We found no reference to how people interpret and infer meanings (in increasingly multimodal forms of communication) and understand scientific discourses in the media in real-life, contextual settings [e.g. Basu and Barton, 2010; Kress, 2003].

4.4 Research-practice divide

The community regularly shares experiences as a means for identifying, monitoring and enhancing good practices, in other words, as a kind of self-regulation and peer-review practices. Our observation of the conference, where most presentations focused on members’ “do’s and do not’s”, reinforced this idea. Analysis of the proceedings book references section showed many links to organizations and project websites but rather few to academic publications (see Table 3). This confirms that academic research has little to no weight on the community’s practice and should prompt further study to explain the motives behind this fact.

Table 3: Analysis of the references section of the CAP 2018 proceedings book.

Personal experiences and “lessons learned” steer a large part of the community’s activities, with little objective evidence of their efficacy or impact. Evaluation seems to be left to a secondary plane, even though practitioners recognize its importance to improve practice. Science communication scholars have put forth several proposals to do so in a systematic manner [Falk and Needham, 2011; Fischhoff, 2019; Jensen and Gerber, 2020], which could create collaboration opportunities between research and practice in science communication. Projects involving storytelling, where this kind of cooperation has shown several advantages to research and practice likewise, may also offer interesting opportunities [Riedlinger et al., 2019]. Yet another example is research on emotions and emotional appeals in the context of science communication, which suggests that they can be an instrument to promote action and a significant predictor of perceived trustworthiness [Reif et al., 2020; Taddicken and Reif, 2020]. This may be useful to confirm if interest (e.g. triggering interest in STEM) and trust are being enhanced by this community. These kinds of collaborations may be useful to guide and adjust action plans, and likely result in better ways of relating to the public(s).

Looking more deeply at the issues of concern to the community, which are frequently discussed in communication research, may be beneficial to the practice of astronomy communication. Reflecting on communication models, symbols and logics used by the media would probably be helpful to promote change in public attitudes regarding misconceptions and stereotypes identified by many of the interviewees. This becomes even more relevant with regard to younger audiences, as they make a constant use of online communication platforms and are, therefore, potentially more exposed to information and opinions about science that circulate in those media, which are more difficult to follow or control.

Several scholars have analysed the potential to promote public debate and participation in scientific processes through social media platforms [Bik and Goldstein, 2013; Brossard and Schefeule, 2013]. This is also a way for scientists to make their work and opinions known [Bik and Goldstein, 2013], and to become influencers and opinion makers on science subjects. Although the media were constantly referred to, we did not find clues that allowed us to think that, in general, this community of practice is using media to promote discussion and participation in science matters. In fact, the work of Entradas and Bauer [2019] showed that astronomers make little use of social media, and many of the CAP network members identify themselves as astronomers. Mostly, the media’s role was confined to publicizing scientific events (such as talks or astronomical observations, for example), disseminating scientific content and enhancing organizational communication (of science institutions). Many studies focus on scientists’ skills to use and comprehend media [e.g. Peters, 2013; Peters et al., 2008; Pinto and Carvalho, 2011] but it is necessary to continue examining these matters in a context where online media have assumed a greater role in the selection of the scientific sources of information that people consume [Brossard and Schefeule, 2013].

The community is skilled in the use of multimedia tools on different platforms and certainly has the potential to use media to foster participation. However, their involvement in dialogical and participatory forms of communication can be much improved.

In our view, citizen science projects have a great potential for public engagement in the sense of democratic participation, as well as for greater interconnection between research and practice in science communication. As put by Lewenstein [Gerber et al., 2020, p. 39]:

“Citizen science is one of the areas where the boundaries of science communication research and practice are getting more diffuse and dissolving because people in that world are trying to ask questions about motivation, recruitment and outcomes to improve their practice.”

However, we found a thin representation of this type of project at the CAP conference with only 5 articles and 8 posters referring to citizen science initiatives in the proceedings book. Some of these make use of social media to encourage people to contribute to the science of astronomy (e.g. by sending photographs or extracting scientific results) and it seems to us that it can be leveraged for a greater diversity of citizen engagement in science.

5 Conclusions

Based on this exploratory study, we can draw several conclusions and reflect on interconnected aspects that are worthy of further research. Firstly, most interviewees in the astronomy communication community tended to homogenize the public and to emphasize deficits and vulnerabilities of several kinds (for instance, the ideas that the public has only a basic knowledge about science, that they have/had little interest in science while at school, and that they are strongly influenced by the media). Most seemed to disregard various factors that may make people’s relationship with science vary. The public is hence mostly seen as having a single role, that is, of a recipient of science information (except concerning science policies, which practitioners admit the public may influence). Given the perceived multiple deficits of the public [Bauer, 2009; Trench, 2008; Bauer, Allum and Miller, 2007], concerns with the risks of misunderstandings and misinformation rise, as well as the perceived need to defend science from such risks [Bucchi and Trench, 2014; Dudo and Besley, 2016]. For a generally unknowledgeable, passive and influenceable audience, the prevailing focus is on the need to transmit the “right message of science”, which is expected to change the public’s attitude towards science and increase interest in science. In addition, showing scientists and science in action to the public appears to be perceived as an important strategy for communication practitioners to re-establish the “truths” of science and foster an emotional connection. By seeing the behind-the-scenes of the scientific enterprise the public would presumably be more interested and supportive.

Therefore, in the interviewees’ speech, we identified two types of functions of the community: a) dissemination of scientific knowledge in order to fill the public’s knowledge deficit; b) bridging the gap between the public and the scientific community, which would allow for a better understanding of the processes of production of scientific knowledge and an increase of interest in science. There is a recognition from the community that the public’s positive attitude towards science enables science to advance, either by promoting research funding or by attracting potential new scientists. Insofar as they perceive the public as influential with regards to science policies, they constitute the members of the public into citizens that function as political agents in democratic societies. The kind of scientific citizenship they expect from their public frames the kind of engagement they promote with science, which is aligned with existing structures of knowledge production and involves only a low level of dialogue.

Although this community of practice recognizes multiple goals for public engagement, many of which are critical to scientific citizenship, it seems that astronomy communicators are still discovering different forms of relating to their audiences. Awareness of, and reflection on, the multiple ways of assigning meanings to science-related issues are ongoing processes and need to be further encouraged. This calls for cultivating linkages between scientific specialties and other subject areas, as well as analysis of social, political and cultural aspects in each context. The transition of science communication practices to “knowledge building” models requires considering the public as an active co-constructor and user of scientific information [Falk and Dierking, 2012; Stocklmayer and Rennie, 2017]. Therefore, the notion that astronomy communication practitioners tend to hold of their audiences seems to limit the relationship they build with the public(s) of science.

Secondly, we observed that as school and media are viewed as sources of some misconceptions and stereotypes, the community tries to liaise with teachers and journalists on a regular basis so that those agents may “transmit” the “message” of science more accurately. Recognizing the critical role of the media in framing science issues and influencing public perceptions and attitudes, the community shows concerns about media distortion of science overall, affecting science credibility. Trust and credibility have for long been a concern for science communication research, especially regarding the public’s perceptions of the credibility of sources of science information [e.g. Bubela et al., 2009; Weingart and Guenther, 2016]. However, it seems that the community holds a traditional stereotyped perspective that holds science as distinct and separate from society at large [e.g. Bucchi and Trench, 2014], which limits their comprehension of other stakeholders’ roles in science communication.

Public trust in science is a critical question that needs to be further explored, especially considering new ways of information circulation, increasingly via social media and other internet spaces where scientists do not always participate. Scientists and science institutions are using “media logics” [Bauer, 2008] in their practices in communicating science to the “end-user”, not always knowing how to deal with the “dynamics and potential risks of such engagement” [Bucchi, 2017, p. 891].

Also, the institutional connections we have found in interviewees’ profiles points to distinct motives for communicating science, and thus the need to consider other factors involved in the trustworthiness of science. Likewise, the growing trend for private funding in science and the instrumentalization of science in political and economic discourses are changing the symbolic environment and challenging traditional forms of certifying the reliability of science information, and, more generally, the social authority of science [e.g. Weingart and Joubert, 2019]. The astronomy communication community needs to be prepared to face growing challenges regarding an open and democratic view of science governance, which call for expanded debates on potential implications of research applications, research funding and research agendas. In our view, this community may be instrumental in challenging the public to take up other (deeper, far-ranging) roles in science governance in collaboration with other agents.

Thirdly, we observed a limited influence of science communication research on this community of practice. We found interviewees to have a limited scholarly knowledge of science communication theory, such as communication models and processes, and audience research. The lack of references to science communication research in CAP participants’ speech and in the CAP proceedings book, as well as the interviewees’ profiles and answers, lead us to conclude that this community does not engage with — or is not aware or knowledgeable of — science communication research. We should ask why that is the case. Topics of interest to the community, such as inclusion and gender balance, are frequently studied in the social sciences [e.g. Mitchell and McKinnon, 2019; Osborne, Simon and Collins, 2003]. As science communication activities grow and become a more professionalized activity, practitioners’ shortcomings to address complex processes of science communication vis-à-vis diversified audiences upsurge. As most practitioners have formal training in science, there is a need for additional training on science communication, as well as for widening collaborations and partnerships with other science communication stakeholders, such as journalists and scholars.

Notably, we identified a need for training oriented to dialogue and to capacity-building of astronomy communicators to foster public participation [Trench and Miller, 2012]. Science communication research mostly refers to “public engagement” as a relationship based on transparent and dialogical communication between citizens, scientists and policy-makers [de Oliveira and Carvalho, 2015]. In this relationship, communication practitioners, as mediators, are expected to play a critical role. Needless to say, an effective collaboration between research and practice is expected to benefit the science-society relationship. Practitioners’ lack of familiarity with science communication research may also be a responsibility of the research community and closed-access publication policies.8 It is thus likewise important that the science communication research community develops new approaches to engage more broadly with practitioners to foster a wealthy exchange of experiences and lessons learned from both sides. There are studies that suggest the existence of several barriers between science communication researchers and practitioners, related to two very different cultures, which may create some tension (see, for instance, Gerber et al. [2020]). This article aims to contribute to help lower some of these barriers, by looking at science communication practice with the lenses of science communication researchers and helping enable a dialogue between the two fields, which will hopefully contribute to boost debate in the forums of these communities, such as conferences and workshops.

Future research may clarify some of the questions that this exploratory study enfolds. The present study offers a “snapshot” of the astronomy communication community at a given moment in time. Since communities of practice are by nature organic and dynamic structures, by observing them we do not expect to find stable “truths” and unique ways of acting in the face of increasingly complex and diverse contexts for the science and society interface. Nonetheless, as various trends, shared ways of seeing and common practices were observed in this study, it is worth examining them, as we have attempted to do, in order to support the community in developing processes of reflexive science communication practice.

Acknowledgments

Sara Anjos held a Ph.D. grant (SFRH/BD/123276/2016) co-financed by FCT/FSE/MCTES through national funds.

Note added. A preliminary version of this study was presented at the ‘VII Jornadas Doutorais em Comunicação & Estudos Culturais’ held in Braga, Portugal, October 14–15, 2019, and is included in its proceedings: Anjos, S., Russo, P. and Carvalho, A. (2020). Comunicar Astronomia: representações do público e implicações para a práxis. In Z. Pinto-Coelho; T. Ruão and S. Marinho (eds.), Dinâmicas comunicativas e transformações sociais. Atas das VII Jornadas Doutorais em Comunicação & Estudos Culturais (pp. 5–8). Braga: CECS.

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Authors

Sara Anjos is a Ph.D. candidate jointly at the University of Minho and at the University of Leiden. Her research interests focus on Science-Technology-Society Studies, particularly on public engagement with Astronomy. Holds a four years university degree in Astronomy, an MSc in Science Education and an MBA. She is an active member of several research groups in the Science Communication and Education intersection and was the Portuguese Language Office of Astronomy for Development — International Astronomical Union (PLOAD-IAU) coordinator until 2017. ORCID: https://orcid.org/0000-0002-8544-7471. E-mail: saraanjos@gmail.com.

Pedro Russo is assistant professor of Astronomy & Society at Leiden Observatory and the Department of Science Communication & Society and coordinator of the Astronomy & Society group. Pedro is the president of the International Astronomical Union Commission on Communicating Astronomy with the Public. He was the global coordinator for the largest network ever in Astronomy, the International Year of Astronomy 2009. ORCID: http://orcid.org/0000-0002-8589-7800. E-mail: russo@strw.leidenuniv.nl.

Anabela Carvalho (Ph.D., University College London) is Associate Professor at the Department of Communication Sciences of the University of Minho, Portugal. Her research focuses on various forms of environment, science and political communication with a particular emphasis on climate change. Her publications include ‘Communicating climate change: discourses, mediations and perceptions’ (2008), ‘Citizen voices: enacting public participation in science and environment communication’ (with L. Phillips and J. Doyle; 2012), ‘Climate change politics: communication and public engagement’ (with T.R. Peterson; 2012). She is Director of the Ph.D. programme on Communication Studies: Technology, Culture and Society. ORCID: https://orcid.org/0000-0002-7727-4187. E-mail: carvalho@ics.uminho.pt.

How to cite

Anjos, S., Russo, P. and Carvalho, A. (2021). ‘Communicating astronomy with the public: perspectives of an international community of practice’. JCOM 20 (03), A11. https://doi.org/10.22323/2.20030211.

Endnotes

1See the report on the Rockefeller Science Communication Conference, at The Bellagio Center, Italy, 6–10 November 2017, Topic 3: Science Communication Practitioner “The world of the science communication practitioner” in https://www.scicom-bellagio.com/2017/12/20/bellagio-the-world- of-the-science-communication-practitioner/ (visited on 18 April 2019).

2For instance, Canfield et al. [2020] have noticed that several practitioners are experimenting with methodologies for inclusiveness in science communication that have not yet been addressed in academic literature.


text:
# Basic statistics calibration question

Hi guys,

My friend was asked the following question in an interview:

There are 3 weight scales and a 10kg weight.
You weigh the 10kg on each scale 5 times (total of 15 measurements for the 3 scales), each measurement is a bit off the 10kg mark (lets say the first scale shows: 11kg, 9.4kg, 12.1kg, 10.6kg. 10.2kg).

You are suppose to choose the criteria of which scales is more accurate.
Why is it better to use standard deviation instead of the medium or average?
How do you create a calibration formula for the scale?

Thanks!

verty
Homework Helper
The question is wrong. It is not better to use the standard deviation. This was a trick question, I think.

I won't say more but think about why the standard deviation might be bad to use.

I wish you would say more though :)
Standard deviation measures the variation from the average. If the standard deviation for one of the scales is smaller the of the others then the measurements are closer to the average... yet, the average could be someting like 20kg which is very far away from the true 10kg. Is that why you ment its not a good indication for accuracy?
So is using the average of measurements for each scale and measuring how far the average is from the 10kg the bets way to measure the accuracy and choose the "best scale"?
How about using the standard deviation formula with the mean value as 10kg instead of the true average of that scale?

Plus, any clarifications about a calibration formula would be great.

thanks

verty
Homework Helper
Yes, my point was that scale A could be less accurate even though it has a smaller standard deviation, if it has a crazy average. Without paying attention to the average, you couldn't calibrate the scale. For me it is more important.

I think by calibration formula they mean a list of steps to follow to calibrate one of the scales as much as possible. I don't you need many hints here, think of Hooke's law and how you would calibrate a scale at home.

Yes, my point was that scale A could be less accurate even though it has a smaller standard deviation, if it has a crazy average. Without paying attention to the average, you couldn't calibrate the scale. For me it is more important.

I think by calibration formula they mean a list of steps to follow to calibrate one of the scales as much as possible. I don't you need many hints here, think of Hooke's law and how you would calibrate a scale at home.

Consider the following set of data:

$$\begin{matrix}500 & 0 & 4922 & 0 & 0 & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 \\ 0 & 4003 & 0 & 0 & 0 & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 & 0 & 0 & 3 & 0 \\ 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 \end{matrix}$$

What's its average? What's its standard deviation? :tongue:

This is something of a ridiculous example, but it shows that in the context of the problem, standard deviation IS the best indicator.

The problem says that each one is "a bit off" the actual value of 10, so the average will be about 10.

Thus, we use our formula for a sample standard deviation, replacing ##\bar{x}=10##, to obtain ##\displaystyle s=\sqrt{\frac{1}{n-1}\sum_{i=1}^{n}\left[(x_i-10)^2\right]}##. The scale with the smallest value of ##s## is the most accurate.

Ok, great demonstration !
Follow up questions: Why 1/(n-1) and not 1/n?
How would you calibrate the following results: 11kg, 9.4kg, 12.1kg, 10.6kg. 10.2kg?

chiro
With regards to n-1 its because n-1 provides an unbiased estimate of the population value.

In statistics we use random variables to estimate population parameters (like mu or sigma). An unbiased estimator means that E[theta_hat] = theta where theta is the true population value and theta_hat is an estimator that represents the estimator distribution of theta.

Ok, great demonstration !
Follow up questions: Why 1/(n-1) and not 1/n?
How would you calibrate the following results: 11kg, 9.4kg, 12.1kg, 10.6kg. 10.2kg?
There are ##n-1## degrees of freedom.

For the data you gave, I would calculate ##s=\sqrt{\frac{(11-10)^2+(9.4-10)^2+(12.1-10)^2+(10.6-10)^2+(10.2-10)^2}{5-1}}=\sqrt{\frac{1+.36+4.41+.36+.04}{4}}=\frac{1}{2}\sqrt{6.17}\approx 1.241975 \text{ kg}##.

Note that the calculation assumes the "average" is 10, so it is not a standard form of standard deviation as much as a measure of the deviation from the "wanted" mean. The average of the data is not 10, but it should be fairly close.