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blauwbilgorgel | 11 years ago

> ... how exactly none of those are the ones with the necessary PhDs in statistics and algorithms to get anything of any value done.

I see it almost the other way around: Companies strictly demand PhD's for Big Data jobs and can't find this unicorn. Yet we live in a time where we don't need a PhD program to receive education from the likes of Ng, LeCun and Langford. We live in a time where curiosity and dedication can net you valuable results. Where CUDA-hackers can beat university teams. The entire field of big data visualization requires innate aptitude and creativity, not so much an expensive PhD program. I suspect Paul Graham, when solving his spam problem with ML, benefited more from his philosophy education than his computer science education.

Of course, having a PhD. still shows dedication and talent. But it is no guarantee for practical ML skills, it can even hamper research and results, when too much power is given to theory and reputation is at stake.

In my experience Machine Learning was locked up in academics, and even in academics it was subdivided. The idea that "you need to be an ML expert, before you can run an algo" is detrimental to the field, not helping so much in adopting a wider industry use of ML. Those ML experts set the academic benchmarks that amateurs were able to beat by trying out Random Forests and Gradient Boosting.

I predict that ML will become part of the IT-stack, as much as databases have. Nowadays, you do not need to be a certified DBA to set up a database. It is helpful and in some cases heavily advisable, but databases now see a much wider adoption by laypeople. This is starting to happen in ML. I think more hobbyists are right now toying with convolutional neural networks, than there are serious researchers in this area. These hobbyists can surely find and contribute valuable practical insights.

Tuning parameters is basically a gridsearch. You can bruteforce this. In goes some ranges of parameters, out come the best params found. Fairly easy to explain to a programmer.

Adapting existing algorithms is ML researcher territory. That is a few miles above the business people extracting valuable/actionable insight from (big or small or tedious) data. Also there is a wide range of big data engineers making it physically possible to have the "necessary" PhD's extract value from Big Data.

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yid|11 years ago

While there's some truth in what you're saying, you sort of demonstrate a very common pitfall:

> Tuning parameters is basically a gridsearch. You can bruteforce this. In goes some ranges of parameters, out come the best params found.

This sounds so simple. However, if you just do a bruteforce grid search and call it a day, you're most likely going to overfit your model to the data. This is what I've seen happen when amateurs (for lack of a better word) build ML systems:

(1) You'll get tremendously good accuracies on your training dataset with grid search (2) Business decisions will be made based on the high accuracy numbers you're seeing (90%? wow! we've got a helluva product here!) (3) The model will be deployed to production. (4) Accuracies will be much lower, perhaps 5-10% lower if you're lucky, perhaps a lot more. (5) Scramble to explain low accuracies, various heuristics put in place, ad-hoc data transforms, retrain models on new data -- all essentially groping in the dark, because now there's a fire and you can't afford the time to learn about model regularization and cross-validation techniques.

And eventually you'll have a patchwork of spaghetti that is perhaps ML, perhaps just heuristics mashed together. So while there's value in being practical, when ML becomes a commodity enough to be in an IT stack, it is likely no longer considered ML.