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Why is machine learning 'hard'? (2016)

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Re: Why is machine learning 'hard'? (2016)

#121

Earlier quoted context omitted.

Here’s an example of something similar. Say you have a baseline model with an AUC of 0.8. There’s a cool feature you’d like to add. After a week or two of software engineering to add it, you get it into your pipeline. AUC doesn’t budge. Is it because you added it in the wrong place? Is the feature too noisy? Is it because the feature is just a function of your existing features? Is it because your model isn’t big eno…

>AUC doesn’t budge. Is it because you added it in the wrong place? Is the feature too noisy? Is it because the feature is just a function of your existing features? Is it because your model isn’t big enough to learn the new feature? Is there a logical bug in your implementation? Or is it because lack of expertise and experience and because someone tries stuff blindly without understanding a bit in the hope they will…

Isn't that all of AI? I get the impression that not even the "experts" really understand what new techniques will get good results - they're guided by past successes, and have loose ideas about why past successes were successful, but can't really predict what else will work.

It seemed like the tremendous success of transformer architectures was a surprise to everyone, who had previously been throwing stuff at the wall and watching it not stick for multiple decades. And when you look at what a transformer is, you can see why QKV attention blocks might be useful to incorporate into machine learning models... but not why all the other things that seem like they might be useful weren't, or why a model made of only QKV attention blocks does so much better than, say, a model made of GRU blocks.

Re: Why is machine learning 'hard'? (2016)

#122

Earlier quoted context omitted.

Here’s an example of something similar. Say you have a baseline model with an AUC of 0.8. There’s a cool feature you’d like to add. After a week or two of software engineering to add it, you get it into your pipeline. AUC doesn’t budge. Is it because you added it in the wrong place? Is the feature too noisy? Is it because the feature is just a function of your existing features? Is it because your model isn’t big eno…

>AUC doesn’t budge. Is it because you added it in the wrong place? Is the feature too noisy? Is it because the feature is just a function of your existing features? Is it because your model isn’t big enough to learn the new feature? Is there a logical bug in your implementation? Or is it because lack of expertise and experience and because someone tries stuff blindly without understanding a bit in the hope they will…

> Or is it because lack of expertise and experience and because someone tries stuff blindly without understanding a bit in the hope they will nail it with enough fiddling?

So, 99% of software development?

Re: Why is machine learning 'hard'? (2016)

#123
post #88

Earlier quoted context omitted.

You are right. That's why you want to avoid doing science, when you can. Ideally, you want to be solving engineering problems instead.

You being? We really need people to try to solve problems that might not work because that is how new technology develops.

Let's rephrase: If you have to solve a problem, you'd better hope that problem is an engineering problem rather than a science problem.

Re: Why is machine learning 'hard'? (2016)

#124

Earlier quoted context omitted.

I dont feel like im doing statistical modeling when i do ml. Usually feels more like pipe alignment, followed by tremendous amounts of debugging.

The heuristic I use for distinguishing between statistical modelling, machine learning and AI is is through feature engineering and model specification: - Statistical modelling: Manual feature engineering, manual model specification (y = ax + b) - Machine learning: Manual feature engineering, automated model specification (y = ax + b or y = ax^2 + b, I don't care, the algorithm should figure it out). - AI: Automated…

IDK about this. The model y = ax + b is not specified, parameters a and b have to be chosen by optimization. Now add regularization that some of those parameters are shrinked to 0 (lasso) and you have "automatated model specification" where only some parameters are left and others discarded.

And furthermore the models are always chosen from a predefined hypothesis set, so there can never be truly automated specification.

Re: Why is machine learning 'hard'? (2016)

#125

Earlier quoted context omitted.

You being? We really need people to try to solve problems that might not work because that is how new technology develops.

Let's rephrase: If you have to solve a problem, you'd better hope that problem is an engineering problem rather than a science problem.

Even many engineering problems are too difficult to know a priori that they will work. No new knowledge is needed as such, just the bounds on what is possible might be fuzzy.

Re: Why is machine learning 'hard'? (2016)

#126
Unless computer scientist really try to understand how actual brain build their networks, I don't think ML will really bring real advances.

Computer science is pointless when it's not applied to another field of science.

Re: Why is machine learning 'hard'? (2016)

#127

Earlier quoted context omitted.

Would there be enough of a financial incentive to do so? Seems like a prime startup opportunity.

I was just thinking the same, but I'm skeptical. When researchers want to publish a paper, are they going to pay extra money for extra difficulty in publishing their paper? No, they'll just use whatever toy environment is free or already established and get that paper published!

[deleted]

Re: Why is machine learning 'hard'? (2016)

#128
post #51

I used to work on an ML research team. In addition to what the author mentions, there is an entirely separate issue: whether or not what you're attempting to do is possible with the approach you've chosen. Consider making an iOS app. For the most part, an experienced software engineer can tell you if making a given app is possible, and they'll have a relatively clear idea about the steps required to realize the idea.…

You nailed where I currently stand. At my company I've been a jack of all trades but mostly software/dba work. My boss and I were very excited about ML when the hype cycle was taking off several years ago and completed a successful project. Fast forward to today, I got loaned out to another team that lost their data scientist, and for the first time in my career I'm having to say - "I don't think we can do what you w…

Every data science team should have a wall decoration with John Tukey's quote "The combination of some data and an aching desire for an answer does not ensure that a reasonable answer can be extracted from a given body of data."

Re: Why is machine learning 'hard'? (2016)

#129
post #5

I'm a bit sceptical of the exponentially harder debugging claim. First it looks polynomially harder for the given example :p. Second other engineering domains arguably have additional dimensions which correspond to the machine learning ones mentioned in the article. The choice of which high level algorithm to implement is another dimension to traditional software engineering that seemingly exists and corresponds to t…

I had similar thoughts on this. It looks polynomial because he classified errors into certain groups and spread them across an axis which we implicitly think is a dimension. But it's not... as he says, "Along any one dimension we might have a combination of issues (i.e. multiple implementation bugs)". So looking at the grid and thinking you're at a single point is wrong... but so is thinking you could be any configuration of locations (you couldn't be at points (1, 1) and (2, 2), you also need to be at points (1, 2) and (2, 1), i.e. the set of points you're at is transitive). Thus this is a bad way to "enumerate the failure cases" and makes his notion of "adding a dimension" pretty unintuitive. It makes more sense to see every point of his dimensions as itself a dimension. Each of these dimensions could be either correct or incorrect, 1 or 0. So you're configuration could be visualized as a string of 1's and 0's. Thus, the number of possible configurations grows exponentially (2^n).

Re: Why is machine learning 'hard'? (2016)

#130

As with everything, if you don't know the fundamentals, the basics, you are very limited on what you can achieve and find stuff difficult. To use a parallel from software if you just know a programming language, how to call libraries and APIs you can't compare to a guy with a solid CS background who also understands algorithms, data structures, complexity, math and knows how computers work down to NAND gates. Because…

> and knows how computers work down to NAND gates.

I lol'd

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