Causality for Machine Learning (2020)
ff13.fastforwardlabs.com
ff13.fastforwardlabs.com
A few headings down:
> Causal inference provides us with tools that allow us to answer the question of why something happens.
This is not necessarily so.
Randomized controlled trials suffer from black box problems the same as models. This is clear enough when thinking about something like a tutoring program. Suppose I randomly assign a bunch of schools to learn algebra with curriculum X and the rest to continue business as usual.
Program X does better, so we infer the program has a causal impact on algebra learning.
However, we still do not know for sure why program X does better, only that it does better. This is important to inform how to take what works about the program and apply it to other circumstances, adapt it, and so on.
I suppose compared to a big data set, we have a better "why" answer to the variation between the outcome and the treatment. The difference being that we actually know the cause of the observed effect with a trial, whereas with correlational analyses we're not so sure. But that's a very deflationary view of "why." I don't mean to be too cynical here; we can always push "real" causality one more level down. For example, suppose we figure out the secret sauce to better algebra teaching relates to a specifical pedagogical practice. We can then say "but why does that practice work? what does it do in the brain?" So I don't want be too reductive.
But even gold standard RCTs don't always give us a "why?" answer. I remember attending a conference about a decade ago among causal inference-devoted social researchers specifically about "the black box" of causal inference as it pertains to RCTs.
But you know that, based on randomized assignment (or at least representative assignment school by school) an impact that A versus B determines.
So you do know E(Y | do(X), Z) to a degree, at least partially.
It never directly answers a "why" or "how" type question. You provide the why/how and then use data to estimate "by how much?"
But that doesn’t mean we can’t answer the question of why something happens. A cause doesn’t cease to be cause just because it also has a cause.
“Causal Inference in Python” by M. Facure https://amzn.to/46byWnl
Well written and to the point.
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I also have a series of blog posts on the topic: https://github.com/DataForScience/Causality where I work through Pearls Primer: https://amzn.to/3gsFlkO
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A similar book is What If by Hernán and Robins. By the end they focus on time-varying treatments, but the first half introduces a lot of the same concepts as this book. What If ia also available for free - https://www.hsph.harvard.edu/wp-content/uploads/sites/1268/2...
In Academia and in "more reputable" projects, domain knowledge is vital to the success of an ML project. This doesn't seem to be the case for startups, looking to make some quick cash. Lots of online articles tout the lack of domain knowledge needed to create models... just googling "machine learning without domain knowledge" brings up a ton of articles saying machine learning is "easy" even without expert knowledge.
Super intuitive explanations and all examples translated to Python code.
A friend recommended it to me and I love it!
https://news.ycombinator.com/item?id=37517137
Only that the article is very long.
I have a hunch that from this path of inquiry and others, we are going to identify and classify modes and methods of reasoning particular to ML systems. I think it seems overly-simplistic to assume that a thinking machine would need to think exactly like a human.
We react to situations and then rationalize why we reacted that way at leisure, and those often turn into excuses and not reasons. It's a story about why you got angry. Why you got angry was something only slightly related to your stated reason.
If an AI can narrow that gap then they will have exhibited the sort of capacity for reason that we expect from them but have yet to even glimpse.
With AI designed for real tasks, not artificial games, it will be probably the same story. They will do a search of depth N in any case, but in situations of time pressure they will keep N very low.
Historically attempts to replicate high level understanding of a human mind to build an AI didn't work. Simulations of low level understanding, like neurons and suchlike did work. We can draw parallels between AI developments and human mind traits as we see them, but they are very shaky constructs. At least as shaky as all these psychology "high level" theories, which try to refine naive human understanding how human mind works.
> We react to situations and then rationalize why we reacted that way at leisure, and those often turn into excuses and not reasons.
I do believe it is not because of limitations of a human mind, but due to training peculiarities. I believe that reasoning itself was "designed" with a goal of communicating inner states of mind to others, by getting an "explanation" that fits the current social situation and helps to reach current social goals. I agree with the idea that politics was a driver of evolution of human intelligence. And it probably still the driver. Humans learned how to apply these new abilities to other kinds of problems, like engineering ones, but it was when their intelligence evolved a lot under a pressure of natural selection driven by politics.
Probably people can do better than that, and could understand themselves a way better, could explain their anger by real reasons, but we still learning to seek excuses from the very young age. We are punished when we have "wrong reasons" for our behaviour and reinforced for "good reasons". The idea of such an education is to eliminate wrong reasons and remove their power to influence a person's behaviour, but the unintended consequence is person's preference for excuses over reasons.
In other words, it is a cultural thing I believe, not some genetic limitations.