So I gotta ask HN...what the heck was so popular about Nests?! It's one thing to be go after shiny lures like new iPhone apps or luxury items...but a Thermostat?!
Mind boggling...
Generally this is an algorithm that might work for one person:
* Is it equal or higher than the upper temperature outside? Run COOLing function (if it exists) until the LOWER inside temperature bound is reached.
* ELSE Is it equal or lower than the lower temperature outside? Run HEATing function (if it exists) until the UPPER inside temperature bound is reached.
In both cases DO NOT continue to run the circulation fans, at least above a whisper quite slow circulation, past the thermal shift operation. Luke-warm airflow makes the system perceptibly anemic and the results dis-satisfactory.
There are a million and one cases where a pdocut could be 10x better with 10% more effort from me,and where that tradeoff is more than worth it (hell, it's why I use Linux). But the average consumer is aggressively turned off by having to do any "work", and the type of person hanging out on Hacker News is very high-percentile for wanting to put a nonzero amount of work into optimizing this type of thing.
If you have a fairly regular life I would think a schedule would outdo ML pretty much all the time, because you know exactly what that schedule should be. ML might be useful for a secret agent whose life is so erratic that a schedule would be useless.
That is to say ML is maybe better than falling back to nothing.
Sounds like in that case it's better to just control things manually.
ML is pattern recognition. Anything outside of that is still AI, but it isn't ML. I can think of very few feature sets we could supply to help predict someone will be deployed to East Asia for a few days other than scraping calendars and mail for religious and military organizations.
From a design perspective, Nest and others are either additively learning in situ to enhance a base model or they are working from a base model that doesn't directly learn, just classifies workflow to categorize observations on a base model. I doubt heavy training is occurring where the Nest and similar is treated as the central compute node.
If the task is clear enough, ML can take it on by itself, but this requires clear rules and an absolutely unambiguous definition of what winning means. For example, the best chess players in the world are machines, and are FAR better than the best human players. Same for Go (the game, not the programming language).
Then it became clear the thermostat wasn't getting enough power from my 2-wire thermostat transformer and that made it even flakier. I finally threw it away and replaced it with a $20 dumb thermostat, which will still be working fine after the zombie apocalypse. No more Nest products for me.
Away from home should be an easy problem to solve assuming Nest can talk to your phone(which is almost 100% true in real life). IN my experience there are several easy heuristics that can achieve ~ 90% precision and recall in home detection, like are you connected to a wifi or even combining it with some IMU data to be more confident.
In the end because most of the house was empty, I let the Nest do its thing and installed a separate mini-split AC in my office I kept set at 72 year-round because that's a sane and reasonable temperature for an office. Don't try to "nudge me into tolerating higher temps", respect my agency and choice about what is a comfortable environment for me to work in.
As a side note, I will never again buy a Nest product.
And then after a few instances, I just turn off all the automation and set up a schedule like normal.
Same with the "away from home" which seems to randomly think I'm away and I have no idea why.
Oh, and the app doesn't show me filter reminders, only the actual device, which I never touch all the way downstairs. There's not even any status to let me know if it's accepted a new dialed-in temperature, as I've had it fail to capture a request, and then I go back, and see it never updated/saved the new temp. Just zero feedback to confirm that the thermostat has responded to any input, and zero notification from the app if this happens.
Just thoroughly unimpressed.
Thankfully I didn't buy this junk, as it was pre-installed by the owner of my rental. Can't imagine actually paying for something that's only real feature is being able to remotely control my temperature once in a while.