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Cuchulainn
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### Re: Universal Approximation theorem

If you're talking about UAT, then what does GD have to do with it?
Oh dear.
UAT talks about activation functon
AF used in GD

Ergo
UAT related to GD.
AF is a confounder here.
Another less than useful 1-liner.
Achtung: I'm writing the requirements. Don't change the problem.

The properties of AF determine how goof GD will be.
Last edited by Cuchulainn on October 21st, 2019, 4:01 pm, edited 2 times in total.
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Approach your problem from the right end and begin with the answers. Then one day, perhaps you will find the final question..
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Cuchulainn
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### Re: Universal Approximation theorem

There is a difference between numerical optimisation and statistical learning algorithms, which I think you and Cuch are missing. The goal of the first is, given f(x), find x0 = argmin x f(x). The goal of the latter is given a training set, find model parameters which lead to the expected error rate being "low enough" by minimising the empirical error rate. See e.g. the textbook by Shalev-Shwartz and Ben-David.
Bayesian optimisation is which?
From Wiki

Bayesian optimization is a sequential design strategy for global optimization of black-box functions[1] that doesn't require derivatives
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Approach your problem from the right end and begin with the answers. Then one day, perhaps you will find the final question..
R. van Gulik

katastrofa
Posts: 8622
Joined: August 16th, 2007, 5:36 am
Location: Alpha Centauri

### Re: Universal Approximation theorem

That was "less than useful", love.

FaridMoussaoui
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Location: Genève, Genf, Ginevra, Geneva

### Re: Universal Approximation theorem

People trying to communicate but not speaking the same language .... This thread is going nowhere.

katastrofa
Posts: 8622
Joined: August 16th, 2007, 5:36 am
Location: Alpha Centauri

### Re: Universal Approximation theorem

Що?

Cuchulainn
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Joined: July 16th, 2004, 7:38 am
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### Re: Universal Approximation theorem

People trying to communicate but not speaking the same language .... This thread is going nowhere.
Correct.
http://www.datasimfinancial.com
http://www.datasim.nl

Approach your problem from the right end and begin with the answers. Then one day, perhaps you will find the final question..
R. van Gulik

JohnLeM
Posts: 372
Joined: September 16th, 2008, 7:15 pm

### Re: Universal Approximation theorem

People trying to communicate but not speaking the same language .... This thread is going nowhere.
Correct.
Too bad, maybe a little bit of good will could help ? For me the topic is good, if I understood it well : "dig in Cybenko Theorem to turn it into a practical tool". This could really help the IA community to understand their tools.

Cuchulainn
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Posts: 60753
Joined: July 16th, 2004, 7:38 am
Location: Amsterdam
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### Re: Universal Approximation theorem

People trying to communicate but not speaking the same language .... This thread is going nowhere.
Correct.
Too bad, maybe a little bit of good will could help ? For me the topic is good, if I understood it well : "dig in Cybenko Theorem to turn it into a practical tool". This could really help the IA community to understand their tools.
I agree. This was always -and still is- the goal. There's a whole bunch of relevant use cases around this topic.
http://www.datasimfinancial.com
http://www.datasim.nl

Approach your problem from the right end and begin with the answers. Then one day, perhaps you will find the final question..
R. van Gulik

Cuchulainn
Topic Author
Posts: 60753
Joined: July 16th, 2004, 7:38 am
Location: Amsterdam
Contact:

### Re: Universal Approximation theorem

That was "less than useful", love.
It's what Wiki says, so it must be right..
Or was it a rhetorical question on your part?
Last edited by Cuchulainn on October 21st, 2019, 8:43 pm, edited 1 time in total.
http://www.datasimfinancial.com
http://www.datasim.nl

Approach your problem from the right end and begin with the answers. Then one day, perhaps you will find the final question..
R. van Gulik

JohnLeM
Posts: 372
Joined: September 16th, 2008, 7:15 pm

### Re: Universal Approximation theorem

Correct.
Too bad, maybe a little bit of good will could help ? For me the topic is good, if I understood it well : "dig in Cybenko Theorem to turn it into a practical tool". This could really help the IA community to understand their tools.
I agree. This was always -and still is- the goal. There's a whole bunch of relevant use cases around this topic.
maybe should we do this work once for all. It is not that hard I think, since I could reuse most of my work. I am sure also that there are a lot of use case / business cases. However is there any sponsor out there for such a study ?

katastrofa
Posts: 8622
Joined: August 16th, 2007, 5:36 am
Location: Alpha Centauri

### Re: Universal Approximation theorem

Last edited by katastrofa on October 24th, 2019, 3:12 am, edited 1 time in total.

JohnLeM
Posts: 372
Joined: September 16th, 2008, 7:15 pm

### Re: Universal Approximation theorem

I see. Meantime, I hear more and more voices warning that billions of public and private money are wasted in a technology without any foundation, thus inefficient. The last time that this legitimacy problem popped up, the artificial intelligence community crossed a 15 years desert as nice as your picture...

ISayMoo
Posts: 2246
Joined: September 30th, 2015, 8:30 pm

### Re: Universal Approximation theorem

People trying to communicate but not speaking the same language .... This thread is going nowhere.
Correct.
Too bad, maybe a little bit of good will could help ? For me the topic is good, if I understood it well : "dig in Cybenko Theorem to turn it into a practical tool". This could really help the IA community to understand their tools.
Or, equally fairly, it could help the numerical optimisation community understand machine learning theory

ISayMoo
Posts: 2246
Joined: September 30th, 2015, 8:30 pm

### Re: Universal Approximation theorem

Oh dear.
UAT talks about activation functon
AF used in GD

Ergo
UAT related to GD.
AF is a confounder here.
Another less than useful 1-liner.
I'm sorry. I will follow your example and start composing my posts from multiple 1-liners. Like the one I responded to above.

JohnLeM
Posts: 372
Joined: September 16th, 2008, 7:15 pm

### Re: Universal Approximation theorem

Correct.
Too bad, maybe a little bit of good will could help ? For me the topic is good, if I understood it well : "dig in Cybenko Theorem to turn it into a practical tool". This could really help the IA community to understand their tools.
Or, equally fairly, it could help the numerical optimisation community understand machine learning theory
re-reading this thread, I think that the real problem is not a language problem, but an ego one. Mixing egos and science is usually a poor idea, as is to bite a tendered hand. Since we all gave a poor image of our discipline up to now, could we start to be constructive ?

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