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Computer Models and the Global Economic Crash

Anti-Globalism passes along a review in Ars of some recent speculation on the role of interconnected computer models in the global economic crash. "If Ritholtz, Taleb, Mandelbrot, and the rest of the computer modeling and financial engineering naysayers are correct about the big picture, then we really are arguably in the midst a bona fide computer crash. Not an individual computer crash, of course, but a computer crash in the sense of Sun Microsystems' erstwhile marketing slogan, 'the network is the computer.' That is, we have all of these machines in different sectors of the economy, and we've networked all of them together either directly (via an actual network) or indirectly (by using the collective 'output' of machines in one sector as input for the machines in another sector), and like any other computer system the whole thing hums along nicely... up until the point when it doesn't."

8 of 361 comments (clear)

  1. Can somebody 'splain this? by seanadams.com · · Score: 5, Interesting

    I am not an economist but I have owned a couple businesses and consider myself a reasonably practical person.

    I have always believed that the vast majority of today's financial instruments have been invented out of thin air for no reason other than to ultimately ensure the employment of bankers and brokers.

    For example, lots of people have a checking account, savings account, credit card, poersonal line of credit, HELOC, brokerage account, and more. I see absolutely no reason why a single account could not offer all those features. The only reason you "need" all that is because the banks created all these funny rules so that they could introduce more and more products and services. This is done so they can charge you more for each of those things, and also to differentiate them from their competitors.

    Besides consumer banking, can somebody explain to me why we NEED "commercial paper"? Yes, I've read the wikipedia page and I know how it's used, but I don't understand why it's needed. If you can't make payroll then you're pulling from your credit one way or another - why do we need separate instruments for a 2 week loan versus a longer term loan, or a credit card, or whatever?

    And don't even get me started on real estate lending...

    It's like freaking starbucks - you can get your banking services just as special as an upside-down triple no foam half calf non fat 160 degree two splenda mocha. But it's one thing for a coffee company to cater to every individual snowflake's desire, and quite another IMHO for something as important as our financial system to become as absurdly complex and fragile as it is.

    As for the people who are really benefitting from all this complexity - well, it's only during recession that we all collectively take a good hard look at who's making a contribution to society and who isn't. Unfortunately the powers that be think they can beat a recession by tweaking some rates, stealing from taxpayers, or shuffling money from one hand to the other. That's just going to hurt us more in the long term. We need to clean this shit up now - get rid of unnecessary products and overhead, and let the unproductive companies go bankrupt. Let the UAW strangle themselves to death. Just get it done.

    1. Re:Can somebody 'splain this? by 2nd+Post! · · Score: 5, Insightful

      I am not an economist but I have owned a couple businesses and consider myself a reasonably practical person.

      I have always believed that the vast majority of today's financial instruments have been invented out of thin air for no reason other than to ultimately ensure the employment of bankers and brokers.

      Actually, probably not. I suspect (I'm a programmer by nature, so my experience with code may apply here) it's more of each institution and "network" offering redundant services until multiple institutions mature to the point where these services collide and become confusing.

      For example, lots of people have a checking account, savings account, credit card, personal line of credit, HELOC, brokerage account, and more.

      That wasn't true one generation ago. My parents had only a checking acount, savings account, and credit card.

      I see absolutely no reason why a single account could not offer all those features.

      With the advent of computers and networks, now it is possible. But 20 years ago? Not possible.

      How would a bank know how much equity you had in your house? How would your credit card company know how much you had in the bank? How would your mortgage company know what your investment amount was?

      Today, you actually have one company that handles all of it (and in cases where they don't, they can still trade information). So now I can have a HELOC, personal line of credit, credit card, savings account, etc, all tied together, in that credit from one reduces the amount of credit available on another, and all paid from the same account.

      The only reason you "need" all that is because the banks created all these funny rules so that they could introduce more and more products and services.

      In this case I actually disagree. Different people have different had different "collateral", so different kinds of credit were available to them. That explains why different products exist. Someone with a house vs someone with a strong credit rating vs someone who had lots of money all had access to different products. Now a single person has access to all of them.

      This is done so they can charge you more for each of those things, and also to differentiate them from their competitors.

      Besides consumer banking, can somebody explain to me why we NEED "commercial paper"? Yes, I've read the wikipedia page and I know how it's used, but I don't understand why it's needed. If you can't make payroll then you're pulling from your credit one way or another - why do we need separate instruments for a 2 week loan versus a longer term loan, or a credit card, or whatever?

      As before, commercial paper was "invented" before credit cards (or business lines of credit or whatever) existed. It satisfied a market need that probably doesn't exist today.

      And don't even get me started on real estate lending...

      It's like freaking starbucks - you can get your banking services just as special as an upside-down triple no foam half calf non fat 160 degree two splenda mocha. But it's one thing for a coffee company to cater to every individual snowflake's desire, and quite another IMHO for something as important as our financial system to become as absurdly complex and fragile as it is.

      It's this statement that brought me to this answer. Software is flexible (soft), so it can be molded quite easily to different needs according to different usages. The problem is that after four versions needs have evolved, but the original code has not, so now you have something complex and fragile that was originally quite simple and straightforward.

      As for the people who are really benefitting from all this complexity - well, it's only during recession that we all collectively take a good hard look at who's making a contribution to society and who isn't.

      So like software, it's only

    2. Re:Can somebody 'splain this? by uncreativeslashnick · · Score: 5, Insightful

      Most of it is the way it is because it evolved that way, and because of the laws/rules under which it all evolved. You paint with too broad a brush when you say that the vast majority of today's financial instruments have been created out of thin air. That's nonsense spoken out of ignorance, the same way a non-geek might say, "why can't software designers create programs without bugs?"

      Commercial paper is a very broad term and encompasses everything from promissory notes to normal consumer checks. Just about any transaction not involving cash or electronic transfer is done with commercial paper. A huge portion of financial transactions are still done with commercial paper. So in the general sense of the term, it is still very, very necessary.

      Now if you want to start examining specific financial instruments, like the derivatives backed by (partially) crap mortgages, we can have a conversation. I think the idea behind those instruments was basically sound, but the things ended up being a lot more complicated than people thought. It makes sense that if you lump a bunch of mortgages together, only a small percentage of those will default, thereby distributing your risk. But in a climate where fraud was rampant and the people signing people up for mortgages had no incentive to make sure people could actually pay those mortgages back, your lump of mortgages has a much higher chance of containing too many bad mortgages to make the resulting instrument profitable.

      The derivatives market had the perverse effect of creating and encouraging that climate, because the mortgage buyers would buy without enough questions because they knew there were buyers who would buy the derivatives without too many questions. The fundamental problem with the whole concept, it seems to me, is that the derivative buyers and sellers forgot to insist on and question the credentials of the individual mortgagees they were investing in. Had they done a little bit of verification there, we might not be in this place right now.

    3. Re:Can somebody 'splain this? by HisMother · · Score: 5, Insightful

      This bullshit is exactly what's wrong with our entire capitalist system.

      --
      Cantankerous old coot since 1957.
  2. The source of the problem by Anonymous Coward · · Score: 5, Insightful

    has nothing to do with computers. The source of the problem is the source of money. Who decides how much money there is? Who reaps the benefits of creating money which is not backed by real productivity? If you're truly looking for the root of the problem instead of symptoms, then you have to find out about the inner workings of the money system. In other news, the "Federal" "Reserve" bank has once more lowered the interest rate. The dollar is now less than 0.25% away from being free (i.o.w. worthless) money.

  3. Re:pointing fingers by AJWM · · Score: 5, Interesting

    Two words: "emergent behaviour".

    No one group of programmers programmed all these computers, there was no single set of specs for the whole network. All the components may well be "functioning exactly as they should be" (although in reality I'm sure there are a few bugs in the systems, but that's irrelevant here), but the system overall may behave in an unexpected way.

    (That said, I don't think that's the whole problem either -- too many people playing a bit fast and loose and less than honestly with other people's money is also part of the problem.)

    --
    -- Alastair
  4. Re:pointing fingers by Znork · · Score: 5, Insightful

    Considering the fundamental basis of the whole system is based on the flawed assumption that credit can be infinitely expanded the current failure is hardly surprising. The Austrian school pointed out the fallacies that caused both the last depression and the current one almost a hundred years ago.

    Computers have very little to do with it. Constructing models to fit political economics rather than to reflect reality is closer to the actual problem.

  5. The model assumptions were ideological by grandpa-geek · · Score: 5, Interesting

    There are two equally valid descriptions of markets. One is by Adam Smith, with the "unseen hand" guiding the markets. Smith markets are well behaved, efficient, and amenable to analysis by what amount to small-signal statistics.

    The other description is by Charles Mackay in his book "Extraordinary Popular Delusions and the Madness of Crowds." In that book he describes the Dutch tulip craze and other bubbles in history prior to the mid 1800's. This economic crash is more of the same.

    The models, probably because of "free market" ideology, assume a market where Adam Smith's "unseen hand" is at work. The modelers don't consider the kinds of markets described by Charles Mackay. Most of the models are based on the Black-Scholes option pricing theory. If you look at the assumptions underlying that theory, they describe good behavior, efficiency, and changes describable by what amount to small-signal statistics.

    Mackay markets are boom and bust, with greed and lies and herd behavior all around. That's what we had. The underlying mathematics has been studied, but not for markets. If you have a pre-LCD TV, an electronic circuit that is non-statistical but related to boom-and-bust market behavior creates the sawtooth sweeps that paint the picture onto your screen.