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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."

24 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 cbiltcliffe · · Score: 4, Insightful

      It's easily explained by the Golden Rule:

      He who has the gold makes the rules.

      There. Explained.

      --
      "City hall" in German is "Rathaus" Kinda explains a few things......
    2. Re:Can somebody 'splain this? by Anonymous Coward · · Score: 4, Funny

      It all goes back to the "invisible fist" of the free market...

    3. Re:Can somebody 'splain this? by Z34107 · · Score: 4, Insightful

      I am also not a financial expert, but I can see a bunch of reasons why financial paper exists.

      Maybe they're like payday loans for corporations. You have a long-term contract due, but not 'till the end of the month, and you want to keep your employees in the meantime. (I'm guessing this isn't as likely; only corporations with outstanding credit ratings can actually have any success in issuing corporate paper.)

      Maybe it's a way of getting a loan without going through a bank or issuing stock. Say you want to build a new factory with payroll rather than actually pay your employees; maybe you're assuming the factory will pay off the interest on the corporate paper and then some.

      The biggest thing at the end of the Wikipedia article you read is that, whatever the reason the money is needed, it's cheaper than getting it from a bank. If a corporation is big enough and has good enough credit, they can issue corporate paper, at a lower interest rate, instead of paying interest to a bank.

      So, that one, at least, wasn't invented by bankers just to secure their own employment. Maybe somebody who actually knows something about this (a banker, maybe?) could enlighten me.

      --
      DATABASE WOW WOW
    4. 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

    5. 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.

    6. 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.
    7. Re:Can somebody 'splain this? by SerpentMage · · Score: 4, Insightful

      Oh come on...

      Here is a question do you have a mortgage or did you pay for your house UPFRONT?

      What about a car? Pay for all of it upfront?

      I am not saying over leverage yourself, but to say companies and businesses don't need credit is completely fool hardy.

      Credit is needed in a system where you are able to make purchases in certain items. The problem is when people over leverage themselves.

      --

      "You can't make a race horse of a pig"
      "No," said Samuel, "but you can make very fast pig"
    8. Re:Can somebody 'splain this? by hey! · · Score: 4, Interesting

      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.

      Neither did advocates of banking deregulation in the 1990s.

      One of the reasons for this "redundancy" is (or used to be) that different rules apply to each kind of account. You used to have have commercial banks, investment banks, and insurance companies, and each did something different under different rules. Then the rules that had been in place since the Great Depression were repealed by Gramm-Leach-Bliley, and suddenly the legal boundaries between these kinds of financial services was gone.

      Subsequently, we are facing the greatest economic crisis since the Great Depression. Coincidence? I'm not entirely sure, but surely some of the problem is that practices and attitudes that were normal in investment banking suddenly started to crop up in other businesses.

      Although Hank Paulson is actually, in my opinion, one of the more decent individuals as a person in the administration, he's very much the wrong man at the wrong time. One of the things he did as head of Goldman Sachs was to convince the SEC to get rid of the "net capital rule". That was the rule that required banks to maintain a certain level of cash on hand to cover cash demands in unusual situations. This is obviously extremely expensive for companies who had to keep huge volumes of cash on hand, losing mind boggling amounts of value even against modest inflation.

      Had the rule been kept in place, we might not have had to pony up seven hundred billion dollars to bail out Wall Street.

      --
      Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
    9. Re:Can somebody 'splain this? by Estanislao+Mart�nez · · Score: 4, Informative

      Instead of doing Shady and immoral accounting practices why not do what honest small business do. YOU HAVE THE CASH ON HAND TO PAY YOUR BILLS.

      Because once a business gets large enough, the cash flow becomes enormously more complex, and very short term credit becomes a cost-effective way of managing cash flow.

      Basically, a business wants to match cash inflows with outflows (and to simplify the model, we'll count "profits" as one of the outflows). The problem is when you know that your business is owed cash that's going to arrive in unpredictable payments over the next 30-90 days. Setting up the cash outflows so that they precisely match the inflows becomes hellishly more complex when the number of transactions gets big enough. Short term debt provides a buffer that allows a business to simplify this.

      In principle, yes, a business could do the same thing by keeping cash reserves as a buffer, too. But when you take into account the time value of money, that really comes down to the same thing: by keeping cash, the business implicitly pays the opportunity cost of keeping that cash. (And with an inflationary monetary policy, of course, the cash itself becomes less valuable over time.)

      So, to sum up, the money owed to the business over the short terms is its accounts receivable; short-term debt allows a business to convert, for a fee, a large fraction of its accounts receivable into cash, and therefore, to draw upon its accounts receivable to finance its operations. I.e., instead of having n dollars of pure, unencumbered cash at its disposal at any one time, it can have n + ((accounts_receivable * reliable_fraction_of_a_r) - interest_on_short_term_debt)); or, equivalently, to keep less unencumbered cash than it would otherwise need to.

    10. Re:Can somebody 'splain this? by Spasemunki · · Score: 4, Insightful

      ...,who are the original spark that started the fire, I do not want to claim it's "their fault", but they are part of the problem)

      This whole post is total bullshit. The notion that, somehow, attempts to counter historic discrimination against blacks and other minorities set off the economic crisis is just foolish. The regulations imposed on certain banks were very modest, and were essentially designed to prevent worthy borrowers from being denied due to where their house was located ("redlining"). Nothing in the CRA requires banks to extend loans to people who can't pay them back. Most of the banks that were hit hardest by the mortgage crises weren't even subject to the CRA, because they weren't commercial banks. Yet the whiners in the pundit class persist in arguing that armies of poor people strong-armed poor, defenseless banks into making bad sub-prime loans. Never mind the studies that have shown that CRA-regulated banks were less likely to make subprime loans, and less likely to re-sell their loans. Never mind the fact that only one in four sub-prime loans originated from a CRA-regulated bank. Yep... poor people. The secret masters of our economy.

      And Jimmy Carter? He might have been a tool of a president, but blaming him for Iran is bizarre. Horrible policy making in the region going back to WWII sunk Iran. Jimmy was just lucky enough to be there when the music stopped.

    11. Re:Can somebody 'splain this? by Red+Flayer · · Score: 4, Insightful

      Your understanding of accounting is way off (and so you shouldn't claim to speak for accountants when you write that gibberish).

      Also there are a few uncertain assumptions in your little 'analysis' -- one, that the seller chooses to reinvest his sale profits with the bank. You claim that most cash proceeds from the sale of houses was deposited in banks -- this is false. Most was actually reinvested in other real property or elsewhere.

      Plus, you ignore the opportunity cost of the funds the bank is due and the risk of default (hence the interest rate on the loan).

      I know the banking industry has its problems, but claiming it's a ponzi scheme is just uneducated. The banking system is NOT dependent on influx of new investors to pay their creditors (leaving a gaping cash hole when new investors stop appearing). They are dependent on the stream of payments from existing debtors. When that stream dries up, their ability to lend dries up, since they become cash-flow negative, and eventually have no capital to lend.

      The problem is that the banks are unwilling to lend when the expected return on their capital outlay is negative. Due to the fluxed up state of the economy, banks in general have decided that lending is unwise, since the risk of default is so high. The big problem is that banks did not properly assign risk to certain loans, so that they undercharged on the interest rate. The reason this slightly relates to a Ponzi scheme, is that as long as another bank was willing to underwrite a risky loan, then bank could get rid of its risk when the property in question was sold. It was a game of hot potato -- whoever was left holding the risky loan when everyone stopped lending lost. And the big problem was that it continued for too long -- eventually the amount of risky loans was so large that almost *everyone* was left holding a sack of hot potatoes. If credit rules had been tightened, rather than loosened, then a few banks would have gotten burnt early, and the problem would not have spiraled.

      --
      "Trolls they were, but filled with the evil will of their master: a fell race..." -- J.R.R. Tolkien on Olog-hai
    12. Re:Can somebody 'splain this? by johnsonav · · Score: 4, Informative

      The part I want 'splained is: Why does anyone think that the stock market is a serious indicator of the state of the economy?

      If you're looking to the stock market as a barometer, you're in for a let down. The price of a stock depends on so much more than just the state of the economy. The only real rule is: historically high stock prices usually indicate overconfidence, and historically low stock prices usually indicate undue pessimism.

      Everyone knows the market is going to be way up in a few years because it is currently highly undervalued...

      You sound like the prognosticators in 1929. But it took 22 long years for the Dow to surpass its pre-depression highs. Don't commit the same sin of hubris that got us here in the first place.

      Maybe if someone was required to hold a stock for a minimum period of time it would make stocks an indicator of something.

      But that would remove one of the main reasons to own stocks, their liquidity. We don't need stocks to be an indicator of anything at all. All they represent is the value the market places on projected earnings.

      I really think that the government could free up a huge quantity of the credit blockade by lending directly to the enduser to force the various credit companies to wake up and try to compete for their markets.

      Now here's where you lost me. You think that banks are going to try and compete with the government, which can borrow money to lend at almost zero cost. Banks have to get their money from somewhere, and their risk of default is seen as so much higher than the government's, that the interest rates they can borrow at are sky high right now. Why would they try to compete with the government at all? They're almost guaranteed to lose.

      If they would just refinance the so called "Toxic debt" mortgages at 3% over prime it would drop the payments down to a point where most of the "toxic" loans would be workable for the debtors and then they wouldn't be toxic. At 3% over prime it would be plenty profitable too. If they would force the mortgage companies to carry the paper on a portion of the loans (selected at random) it would guarantee that they wouldn't write fraudulent loans either...

      I think you underestimate the scale of the mortgage problem. There is too much debt out there on homes that are worth nowhere near what is owed. What incentive does the homeowner have to repay a loan when they are $100,000 underwater? Even at a zero percent interest rate, it just doesn't make sense for the borrower. Those toxic loans are called "toxic" because there's really no good way to fix them.

      --
      ... and that's when the C.H.U.D.'s came at me.
    13. Re:Can somebody 'splain this? by billcopc · · Score: 4, Insightful

      Banks have to get their money from somewhere

      No, they don't.

      Fractional reserve is the root of our problems today. The system is designed to lend out more money than actually exists, thus the economy is overloaded by design, and inflation is guaranteed.

      Well I don't know about you, but I'm pretty sure them cows don't produce 3% more milk with each passing year, nor do they yield 3% more meat. You can say what you want about wealth, but there is a fixed amount of natural, life-sustaining resources in the world, and printing more money isn't going to change that.

      --
      -Billco, Fnarg.com
  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. pointing fingers by girlintraining · · Score: 4, Insightful

    I'd just like to point out the bleedingly obvious: That people programmed these computers. They are functioning exactly as they should be. If they weren't, we'd have heard about it by now. So the problem is not the computers, or the network, but rather the people who control them. Thank you. You may now resume your regular ranting, already in progress.

    --
    #fuckbeta #iamslashdot #dicemustdie
    1. 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
    2. Re:pointing fingers by BigTom · · Score: 4, Interesting

      What is tightly regulated? Half the Quant algo trading models get thought up in the evening, coded overnight and activated in the market the next morning.

      If you try and slow them down they just run to the head of the desk bleating that the "nasty IT man stopped me making $1000,000,000 for the bank with his silly QA nonsense" and whoosh, its in production. It is prop trading so its their risk.

    3. 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.

    4. Re:pointing fingers by DragonWriter · · Score: 4, Insightful

      Two words: "emergent behaviour".

      Its not emergent behavior of computer systems. Its the exact same kind of behavior markets have displayed without computers.

      Sure, things haven't been this bad recently, so some elements of it are new, at least in the short term, and the details change always. But none of the big picture stuff has much to do with computers, fundamentally. Economic markets are vastly interconnected because their substantive outputs and inputs (not just data outputs and inputs of the computer systems currently used as tools in managing them) are directly linked.

      Blaming computers is about as justified as blaming witches.

    5. Re:pointing fingers by girlintraining · · Score: 4, Insightful

      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.

      There's a bug in Internet Explorer. That must mean the entire internet is broken. No. Financial transaction systems are heavily audited, rigorously tested, and subjected to heavy regulation. They are the most hardened systems in wide use in the commercial sector. Period. That doesn't mean there aren't problems, but a problem big enough to cause a network-wide malfunction are very, very low.

      What we're dealing with now are people who made bad assumptions about the economy, got cocky, and now we all are paying the price for the lack of oversight and auditing done on the decision-makers responsible. Looking for simple solutions (ie, "the computer did it") to complex problems is naive at best. This took many several thousand people, all making the same bad decisions, to bring us to where we are now. I will say it again -- this is not a technological failure, it's a failure of people. And if you ask me, we should start publishing the "bugs" -- ie, the names and faces of these people, so the rest of us know to never let them anywhere near the financial sector ever again.

      But that would just be too easy.

      --
      #fuckbeta #iamslashdot #dicemustdie
  4. Can't model in human traits by HW_Hack · · Score: 4, Interesting

    How can you model in greed - corruption - and the ever popular human trait of freaking out ?

    Tech bubble - Real Estate bubble ... next time I even see/hear the word bubble in the markets I'm cashing out for a while

    --
    Its not the years, its the mileage .....
  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.

  6. Taleb's explanation of the Narrative Fallacy by icke · · Score: 4, Informative

    http://en.wikipedia.org/wiki/Nassim_Taleb "Narrative fallacy: creating a story post-hoc so that an event will seem to have an identifiable cause."