Why Get Fuzzy About Logic?

| 56 Comments | No TrackBacks

Historical stock chart
Figure 1: Financial markets exhibit variations at all time scales with amplitude proportional to period. Based on data from stockcharts.com.


Yesterday kicked off the first day of the NIWeek 2009. This is the annual National Instruments user group meeting. NI to followers of this company, makes hardware and software for data acquisition and control applications. For general engineering and research laboratory software, the company's LabVIEW product enjoys a dominant position. The way the company has built and maintains this position is by working hard to anticipate major technology trends that will affect their users, and what their executives learn from this ongoing exercise comes out in comments during keynote speeches at NIWeek.


During NI Chairman James Truchard's opening comments this year, he expressed the opinion that some of the economic difficulties we have experienced globally over the past year can be traced to inappropriate use of mathematics in finance


"... Mathematics, the way it has been taught in business schools the last few years," he said, "has a serious problem ..."


Dr T, as he is known to his friends in the industry, also trotted out the oft-quoted comment by Warren Buffet: "It seems like the higher mathematics, with more false precision, should help you, but it doesn't."


This reminded me of a couple of themes I've been studying over the past few years chaos and fuzzy logic as they apply to things in general, and financial markets in particular. These are surprisingly easy to understand, easy to explain, and universal in application.


Chaos has bad connotations in western philosophy, which guides most of what we do for better or worse. In western thought, chaos is the enemy of order, and one of western civilization's stated goals is maintaining order. Eastern philosophy, on the other hand, seeks to balance the "forces" of yin and yang. These are complex concepts, but the important point for this discussion is that, among other things, yin is an order-seeking force, and yang is a chaos-seeking force. The theory is that both yin and yang are necessary for good health, and specifically must be maintained in an dynamic balance.


Mathematically, chaotic systems can most easily recognized by being in constant motion with cycles represented at all time scales, and the amplitudes of these motions are roughly proportional to their periods. Thus, weekly fluctuations tend to have an amplitude 5-10 times larger than daily fluctuations, with the largest amplitude movements appearing on decades-long time scales.


What makes chaos important is that it can be shown to govern the operation of virtually every complex system, from ocean waves to all human history. If it's a large dynamic system with lots of independently moving parts, its behavior most likely is chaotic.


Fuzzy logic, on the other hand, seems unmathematical for a different reason. The term sounds like a synonym for "fuzzy thinking," which people associate with foolishness and ignorance. Mathematically, however, fuzzy logic is a way of dealing logically with things that cannot be precisely quantified.


Humans, in fact, make nearly all personal decisions - especially life-and-death decisions - using fuzzy logic.


When you merge your car into a busy traffic lane, for example, you don't get out a radar gun to precisely measure the speeds of vehicles already in the lane, then analyze video images of the spacings between cars, then do a calculation based on the measured data plus known performance of your vehicle at various settings of throttle and steering controls. You don't have the equipment available to make the measurements, and you wouldn't have time available to make the calculations if you did.


Instead, your brain converts sense impressions and memories from previous encounters into more-or-less broad categories. Spaces between other cars, for example, are "tight," "okay," or "really big." Their speeds are "slow," "medium," or "fast." Your car "accelerates fast," "moves out okay," or "handles like a dead whale." Instead of a dozens of variables with 12-bit precision, your brain reduces the data set to a handful of variables with at most two-bit precision. It also doesn't use arithmetic to work out the answer, but a fuzzy logic algorithm that resembles a decision tree. The answer comes back as "it's safe - go for it;" "gee, it's borderline," or "that looks like a trip to the emergency ward." The final fuzzy calculation says "no" in the last instance, causes you to look further in the middle instance, and spurs you into action in the first instance.


That's fuzzy logic. It's the fastest and most reliable way to make difficult decisions when time is limited (as it always is). It's also virtually the only way to deal with chaotic systems, which, as I said above, almost all real systems are.


Probably (in a fuzzy-logic sense) the way to solve the problem Truchard and Buffet identified, is by mentally taking chaos and fuzzy logic out of the "advanced mathematics" cubbyhole, and teach it to high-school freshman. If we did that, we'd quickly have a generation with the mental tools needed to analyze and deal with the real world, rather than a hypothetical world of mathematical abstractions.

No TrackBacks

TrackBack URL: http://www.cgmasieyeontechnology.com/mt-tb.cgi/21

56 Comments

Epic. It's a real shame more folks haven't heard about this place, it had exactly what I needed to know :)

if every editor wrote like you believe me the world would be a better place! this was an excellent read expecting more!

I truly like keeping up with these posts! It honestly adds something to my day.

Very interesting and useful article.

What would happen if we took his perspective seriously?

Well, your article is the greatest on this notable topic. I concur with your conclusions and will eagerly look forward to your upcoming updates. Saying thanks will not be enough, for the extraordinary clarity in your writing. I will immediately grab your feed to stay informed of any updates. Admirable work and much success in your business enterprise!

This is really among the most interesting websites I have seen. It's so easy to get jaded, but there is really still some terrific things on the net, and I think your blog is on the short list!

Arrg, my mouse got jammed. What I was about to say, was that this is a terrific post. Very insightful and informative at the same time.

Will you do a follow up article?

Hey very nice blog!!....I'm an instant fan, I have bookmarked you and I'll be checking back on a regular....See ya

Thanks for some quality points there. I am kind of new to web surfing, so I printed this off to put in my file, any better way to go about keeping track of it then printing?

Hey there - I just needed to give you thanks since you shared your thoughts on us all. After I read the post, I am interested in some of your opinions on these latest earthquakes in Haiti, Chili, Japan, and Turkey.

i think you have a pretty nice site here... today was my first time coming here.. i just happened to find it doing a google search. anyway, excellent post.. i'll be bookmarking this blog for sure.

Hello from Russia . Great Work . Keep Posting Awesome Articles Like This .

I am not new to blogging and truly value your site. There is much special subject that peaks my interest. I am going to bookmark your internet site and keep checking you out.

Nice site! I adore several from the articles which were written, and particularly the comments posted! I will definately be visiting again!

Hello, I tried to e-mail you regarding this post that i have a few inquires, but can't seem to achieve you. Please email me when get a moment. Thanks.

Cute photos! LOL. I find it so interesting!! Thanks for sharing this brilliant post.

howdy there, i just saw your blog via google, and i would like to tell that you compose awesomely good on your blog. i am really taken by the way that you write, and the message is good. in any event, i would also like to acknowledge whether you would like to exchange links with my site? i will be to the great extent than willing to reciprocate and insert your link off in the link section. waiting for your response, i give my sincere thanks and have a great day!

very good article,thans for your sharing

Thanks for your helpful Post, I hope you have a good day!

Informative information and excellent posts you have!

I truly appreciate you taking the time to post this. I really liked reading it and am looking forward to more posts from you! Keep 'em coming.

Excellent read, I just passed this onto a colleague who was doing a little homework on that. And he in fact bought me lunch because I found it for him

That's great.very helpful,thanks a lot

Really nice post here - I don't know why you don't just get the most out of these tools whilst they are free.

Thank you for your article,It's well written, in depth posts like these that have aided me in becoming a good forex trader.

I truly appreciate you taking the time to post this. I really liked reading it and am looking forward to more posts from you! Keep 'em coming.

I truly appreciate you taking the time to post this. I really liked reading it and am looking forward to more posts from you! Keep 'em coming.

Thank you for your article,It's well written, in depth posts like these that have aided me in becoming a good forex trader.

Good day from Spain! Will i be able to quote a post as part of your blog using the link to you? I've tried contacting you about this issue but it seems i cant reach you, please response when get a time, thanks.

Hi, Thanks. Having been going through exactly the same problem. Solved now Regards.

Thanks for the share, I have been readin online all day and this was actully worth reading. Thanks

Thanks for the share, I have been readin online all day and this was actully worth reading. Thanks

That's great.very helpful,thanks a lot

very good article,thans for your sharing

I was very pleased to find this site.I wanted to thank you for this great read I definitely enjoying every little bit of it and I have you bookmarked to check out new stuff you post.

Great information that is much appreciated. Thank you for providing such interesting content in my quest to lose the flab.

That's great.very helpful,thanks a lot

Very good text. I've found your site via Google and I'm really glad about the information you provide in your articles.

very good article,thans for your sharing

Informative information and excellent posts you have!

I truly appreciate you taking the time to post this. I really liked reading it and am looking forward to more posts from you! Keep 'em coming.

I truly appreciate you taking the time to post this. I really liked reading it and am looking forward to more posts from you! Keep 'em coming.

Now and then I'll stumble across a post like this and I'll recall that there really are still interesting pages on the web. ^_^. Thanks.

Thank you for your article,It's well written, in depth posts like these that have aided me in becoming a good forex trader.

Very good text. I've found your site via Google and I'm really glad about the information you provide in your articles.

This read was very worthwhile, the tips was definitively great! Keep up the great work.

Excellent read, I just passed this onto a colleague who was doing a little homework on that. And he in fact bought me lunch because I found it for him

That's great.very helpful,thanks a lot

Excellent read, I just passed this onto a colleague who was doing a little homework on that. And he in fact bought me lunch because I found it for him

Great information that is much appreciated. Thank you for providing such interesting content in my quest to lose the flab.

Wow! really piece of information, I had come to know about your site from my friend shubodh, kolkatta,i have read atleast nine posts of yours by now, and let me tell you, your site gives the best and the most interesting information. This is just the kind of information that i had been looking for, i'm already your rss reader now and i would regularly watch out for the new posts, once again hats off to you! Thanks a lot once again, Regards, Multibagger

I don’t usually reply to posts but I will in this case, great info…I will bookmark your site. Keep up the good work!

Leave a comment

About this Entry

This page contains a single entry by C.G. Masi published on August 5, 2009 12:50 PM.

Sorting the Computer Wheat from the Chaff was the previous entry in this blog.

If It's Too Good To Be True ... is the next entry in this blog.

Find recent content on the main index or look in the archives to find all content.