<instructions>Your goal is to analyze the following comment and estimate how highly it will be upvoted by the Hacker News community.</instructions><comment><author>iramiller</author><text>Why not setup a system that detects the presence of your Bluetooth phone?  Perhaps even look for your phone on the wireless network if a sensitive detector is not sufficient?&lt;p&gt;It would not be a stretch at that point to have a simple website served from the device that let you see the history and choose some basic night/day setback points.&lt;p&gt;It takes some time to raise/lower the temperature of the house depending on the outside temperature so learning the rate at which the house warms/cools is required to reach the desired set point at the requested time.  Including the local weather forecast as a sensor and being able to see a graph of temps and system demand cycles would be really nice.</text><parent_chain><item><author>brk</author><text>This is interesting.  I&apos;ve been involved in home automation for about 15 years now, and HVAC controls are one of the top things to control in most systens.&lt;p&gt;Occupancy sensing is also extremely difficult to do passively in any kind of reliable scenario, especially when your occupancy sensor is limited to a single location in the house.&lt;p&gt;I&apos;ve frequently seen two broad categories around regulating HVAC systems:
1) People keep a fairly regular schedule, and a standard 7-day programmable thermostat works sufficiently.&lt;p&gt;2) People keep a very non-regular schedule, and a standard programmable thermostat doesn&apos;t work, nor is there any inferable pattern to their home/away schedule.&lt;p&gt;In case #2, it is usually more beneficial to get home/away status from something with a more direct output eg: a burglar alarm system, vehicle presence detectors in the garage (photobeams), status of lights, etc.&lt;p&gt;I&apos;ll be very curious to see what the real-world reactions are to the Nest thermostat.  If they can come up with some truly creative solutions it could be a really cool device.</text></item></parent_chain></comment><story><title>Nest - The Learning Thermostat</title><url>http://www.nest.com/</url></story>
<instructions>Your goal is to analyze the following comment and estimate how highly it will be upvoted by the Hacker News community.</instructions><comment><author>_delirium</author><text>From what&apos;s on the website it looks like they&apos;re trying to learn largely from user feedback of the &quot;I wanted it cooler/hotter&quot; variety. Agree that this will be a problem in case #2, without good occupancy sensing, because the prediction problem is inherently impossible to do well with only time-of-day-and-week if there isn&apos;t much regularity.&lt;p&gt;I would guess the real target audience is people who fall into #1 but never get around to programming their thermostat, and maybe don&apos;t even have an accurate self-assessment of their home/away or sleep/wake patterns. In particularly warm or cold climates this might also include people who make wrong guesses about latency, e.g. how early before they return the heater needs to kick on for it to be comfortable by the time they get home. I could see it being useful in that case: there&apos;s a regular enough pattern to infer a reliable heating/cooling schedule, but the person doesn&apos;t want to, or isn&apos;t able to manually program that pattern.</text><parent_chain><item><author>brk</author><text>This is interesting.  I&apos;ve been involved in home automation for about 15 years now, and HVAC controls are one of the top things to control in most systens.&lt;p&gt;Occupancy sensing is also extremely difficult to do passively in any kind of reliable scenario, especially when your occupancy sensor is limited to a single location in the house.&lt;p&gt;I&apos;ve frequently seen two broad categories around regulating HVAC systems:
1) People keep a fairly regular schedule, and a standard 7-day programmable thermostat works sufficiently.&lt;p&gt;2) People keep a very non-regular schedule, and a standard programmable thermostat doesn&apos;t work, nor is there any inferable pattern to their home/away schedule.&lt;p&gt;In case #2, it is usually more beneficial to get home/away status from something with a more direct output eg: a burglar alarm system, vehicle presence detectors in the garage (photobeams), status of lights, etc.&lt;p&gt;I&apos;ll be very curious to see what the real-world reactions are to the Nest thermostat.  If they can come up with some truly creative solutions it could be a really cool device.</text></item></parent_chain></comment><story><title>Nest - The Learning Thermostat</title><url>http://www.nest.com/</url></story>