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Predict the future with Machine Learning

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11–20 of 46 posts

Re: Predict the future with Machine Learning

#11
I'm a PhD candidate related to statistical forecasting and projection related to natural science (hydrology/streamflow projection under climate change uncertainty).

The article seems to be a decent introduction article that shows what Machine Learning is about (which is great) and shows how it can POSSIBLY be applied to forecasting and prediction. However, I think it would be even better if there was a simple example or two with each method being applied and showing different outcomes and then the significance of each methodology through those examples.

Also, I'd like to add a comment to this.

This article is great when you look at it from the Machine Learning perspective. However, when you look at it from a forecasting perspective it only shows a very small portion of what forecasting/predicting really is.

Algorithms you develop through machine learning is something known as a black-box model. You know that the input data and the output data you're matching up with are related somehow, but don't know exactly how they're matched up. That relationship is established based on a performance index determined from a trial-and-error method (of course depending on what actual method you use).

There are different methods available such as ARMA and ARIMA based models. In regards to physical science, there are models that focus on the physical interaction between the input data to simulate what is happening inside the system. ML methods are simply just a taste of other methods available.

Regards to programming use (as I'm sure most of you folks here are used to), ML is a good tool to use for forecasting if you're really interested in it. But just like any forecasting model you use, you should probably determine the performance of your model based on not one index but multiple indices which consider different parts of your "needs". Percent accuracy only shows how accurate you are, you should probably also consider how frequently you're over-estimating vs under-estimating, how many series of overestimation there is, etc. The most important one though in my books is bias correction. When working with ML Algorithms most of them do not consider for bias. So you, as the modeller need to prepare for bias correction. However this article kinda glossed over it by saying "right amount of data" and "combination of data" (which I understand is an introductory post, but I think this is very important).

Maybe look into applying a method like the K-Fold Cross Validation to make sure the final output parameters aren't AS biased. It really depends on the modeller and the model and your performance indices you use.

Re: Predict the future with Machine Learning

#12
For anyone who still sees ML as a big of a magic black box, I can't highly recommend this book enough: https://www.amazon.com/Make-Your-Own-Neural-Network-ebook/dp... it does a fantastic job of breaking down the concepts into incredibly straightforward ideas.

In fact, the linked article does (IMO) a terrible job at touching on NN by displaying a large equation without a great deal of context - possibly the last thing anyone actually needs when trying to grok the basic principles behind a NN

Re: Predict the future with Machine Learning

#14
post #9

We shouldn't ever confuse machine learning with predicting the future -- just because you've never encountered a black swan in the wild, doesn't mean they don't exist. That being said, the article otherwise seems like a great introduction. Not sure why they chose that title.

It is an unfortunate misconception that statistical probability can be used to predict the future. Any time you extend a statistical model temporally it immediately becomes mathematically invalid since probabilistic statistics are only valid for a fixed population at a fixed moment in time. Unfortunately business and government is rife with people predicting the future based on statistical models that have no more ma…

What??? Prediction is certainly a type of extrapolation, but to claim that it's "mathematically invalid" reveals a severe lack of knowledge on your part. In fact, under parametric assumptions about the data generating mechanism, we can exactly quantify the expected coverage of prediction intervals. That's literally a standard topic in an introductory statistics course.

Re: Predict the future with Machine Learning

#16
Future cannot be defined for a any stochastic process with unknown number of hidden variables with unknown weights. Everything core complex than a roll of a dice is unpredictable by definition, just because the model is incomplete. Even next roll of a dice cannot be predicted.

Probability is not reality. Simulations are cartoons. Map is not the territory. Models and simulations based on them are different from reality in the same way a movie is not reality.

People who can't grasp these simple ideas cannot be legitimately called scientists.

Re: Predict the future with Machine Learning

#17

I would like to read mathematical foundations of machine learning written for those who are bad at calculus but good at discrete mathematics and algorithms. For example, I'm learning algorithms, participate at contests, quite comfortable with combinatorics and discrete probability theory but I'm absolute zero at calculus. I would like to read machine learning's math introduction which is friendly to my "discrete" bra…

I am in the same boat. I get the feeling that most Calculus books are just a compilation of tips and tricks. So I am suggesting you invest time into learning real analysis proper. Right now I am learning from [1]. It follows Rudin closely and as opposed to many other analysis books meant to "better explain" stuff, it goes deep into the trenches and actually tackles the subject.

[1] https://www.amazon.com/Real-Analysis-Lifesaver-Understand-Pr...

I think time invested into studying real analysis pays off because then you can later study measure theory, functional analysis and more advanced probability to deal with curse of dimensionality and whatnot.

edit: I started studying the book linked above starting from chapter 4 since the first 3 chapters are familiar from discrete math. Then did chapter 5, skimmed chapters 6(little linear algebra), 7, 8 (most "transition to higher math" books contain this stuff) and am currently in chapter 9.

Re: Predict the future with Machine Learning

#18
post #16

Future cannot be defined for a any stochastic process with unknown number of hidden variables with unknown weights. Everything core complex than a roll of a dice is unpredictable by definition, just because the model is incomplete. Even next roll of a dice cannot be predicted. Probability is not reality. Simulations are cartoons. Map is not the territory. Models and simulations based on them are different from realit…

You don't need perfect simulation, just a good enough one. Simulation is like a dynamic, extensible dataset. Neural nets can learn from simulation not only in game play, but also in genetics, robotics and general reasoning. I think simulation is at the core of what will lead to AGI.

Re: Predict the future with Machine Learning

#19
post #18
post #16

Future cannot be defined for a any stochastic process with unknown number of hidden variables with unknown weights. Everything core complex than a roll of a dice is unpredictable by definition, just because the model is incomplete. Even next roll of a dice cannot be predicted. Probability is not reality. Simulations are cartoons. Map is not the territory. Models and simulations based on them are different from realit…

You don't need perfect simulation, just a good enough one. Simulation is like a dynamic, extensible dataset. Neural nets can learn from simulation not only in game play, but also in genetics, robotics and general reasoning. I think simulation is at the core of what will lead to AGI.

My comment was is about inevitable philosophical gap between reality and any model or a simulation, which cannot be bridged in principle.

Yes, simulators as sources of sensory input to get similar experience are used, for example, to train airline pilots. Nevertheless, there is no airline which train its pilots on a simulator only. Algorithm, like a pilot, would learn a simulation, not reality.

Re: Predict the future with Machine Learning

#20
To me as an AI novice this article seemed like a good overview. It did not address one problem I have with AI however, which is the inherent lack of transparency. That is, unlike normal programs, we have an input and an output, but the reasoning in between is a black box to human intelligence. This problem has to be solved before we can turn over any really vital tasks to AI with confidence IMO.
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