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Re:A watershed moment for protein structure prediction by perl4ever on Tuesday January 21, 2020 @09:55PM (#22114156)
It may be because I'm not an expert that I think I understand, but the gist of making a model explainable sounds straightforward from what I've read. You train a model that does who knows what, and then you define a very limited language and use ML to match the first model as well as possible. If the language is simple enough, humans can understand it, and according to what I read, it likely generalizes better than the original model as a bonus. I assume it's harder than it sounds though.

Quote:

"1. There’s a tiny functional language based on a small number of side-effect free combinators

2. For a given task, a program template (which the authors call a sketch), further constrains the set of programs that can be learned for the problem in hand. This also very handily constrains the search space of course, helping to make learning a suitable policy program tractable.

3. To help guide the search within the set of programs conforming to the sketch, a standard reinforcement learning algorithm is used to learn a (black box) policy.

4. The black box policy is used as an oracle (the Neural Policy Oracle), and a neurally directed program search (NDPS) tries to find the sketch-conforming program that behaves as closely to the oracle as possible."

The paper described:

http://proceedings.mlr.press/v80/verma18a/verma18a.pdf

...this seems kind of similar to the recent success in solving mathematical equations using deep learning. The language translation paradigm seems to have a lot more potential than some realized.

Re:A watershed moment for protein structure prediction by mlthoughts2018 on Friday January 24, 2020 @07:19AM (#22137423)
Yes, you are oversimplifying what is required to make a model explainable. The logical mechanism of the functional form of the model has very little to do with explainability. Explainability involves various kinds of model checking, overfitting analysis, tests for confounding variables, multicollinearity, interaction effects, model misspecification, etc.

Merely decomposing a prediction into say a linear combination of predictors does not, itself, provide any type of explanation unless a variety of more complicated assumptions about statistical model checking turn out to be true.

Even worse, because the naive approach is to just treat those regression coefficients as if they do automatically give explanatory power or feature-wise attribution, people misrepresent things unwittingly and don’t carry out enough robust model checking, leading to wrong explanations that appear to have deceptive degrees of confidence associated with them.

Re:A watershed moment for protein structure prediction by perl4ever on Friday January 24, 2020 @09:26PM (#22144225)
"The logical mechanism of the functional form of the model has very little to do with explainability"

I'm not sure we are talking about the same thing, or which of the three sources in my comment you are reacting to.

My understanding of "explainability" in this context is that it means "humans can understand why the model gives a certain prediction".

It seems like you are using it to mean "humans can understand why the thing modeled does something (presumably by referring to the model)". That isn't what I thought people meant by the term, nor does it seem like a reasonable goal to me.

Do we agree these are distinct ideas? Feel free to elaborate on where I've gone wrong.