3 ms·
I think the real biggest "gotcha" is not understanding where the control loops are in your data. The classic example is the "air conditioned room" thought expe
by bloaf 4y ago
I think the real biggest "gotcha" is not understanding where the control loops are in your data.
The classic example is the "air conditioned room" thought experiment. Imagine feeding an AI model a dataset with a bunch of datapoints like this
Room hot | AC on full blast
Room cold | AC off
Room warm | AC on 50%
Then asking the AI how to make a hot room cold. The AI is very likely to say "turn off the AC" because "AC off" is a feature of cold rooms.
Maybe we think that if we give the AI more information, it could do better. Lets imagine that our room has a window and an oversized AC. We'll now be feeding it info about the source of heat as well as the source of cold, so surely it will get the right answer this time:
Window open | AC on full blast | Room cold
Window closed | AC off | Room cold
Window 50% | AC on 50% | Room cold
This dataset is going to have the AI thinking that neither the window nor the AC impact room temperature, and that you might be able to close a window by turning off the AC.
The key thing to understand is that control loops change the "physics" of your system and that knowledge about the control-physics does not transfer to the uncontrolled-physics.
- nl 4y agoMachine learning can deal with this very easily by incorporating time as a feature.
- cwilkes 4y agoThat’s the point: without knowing that time is an important feature your ML model will come to the wrong conclusion.
- nl 4y agoI don't think that was the point the OP was making. I think they were trying to argue that ML cannot learn control loops or maybe that the system needs to "understand" physics (Not sure - it wasn't really clear to me). The fact there is a control loop here doesn't actually seem important if you represent the features correctly. I'd argue that data representation is actually what you need to get right (ie, in this case the behavior in the time domain).
- skybrian 4y agoThe correlation exists. If you see that the AC is running a lot then you can predict that the outside temperature is warmer. What machine learning algorithms even try to determine causation?