Garbage In, Money Out

In my Forbes column last week, I discuss the incredible similarity between the computer models that are used to justify the Obama stimulus and the climate models that form the basis for the proposition that manmade CO2 is causing most of the world’s warming.

The climate modeling approach is so similar to that used by the CEA to score the stimulus that there is even a climate equivalent to the multiplier found in macro-economic models. In climate models, small amounts of warming from man-made CO2 are multiplied many-fold to catastrophic levels by hypothetical positive feedbacks, in the same way that the first-order effects of government spending are multiplied in Keynesian economic models. In both cases, while these multipliers are the single most important drivers of the models’ results, they also tend to be the most controversial assumptions. In an odd parallel, you can find both stimulus and climate debates arguing whether their multiplier is above or below one.

How similar does this sound to climate science:

If macroeconometrics were a viable paradigm, we would have seen major efforts to try to bring this sort of model up to date from its 1975 time warp. However, for reasons I have documented, the profession has decided that this macroeconometric project was a blind alley. Nobody bothered to bring these models up to date, because that would be like trying to bring astrology up to date.

This, from Arnold Kling about macroeconomic models could have been written just as well to describe the process for running climate models

Thirty-five years ago, I was Blinder’s research assistant, doing these sorts of simulations on the Fed-MIT-Penn model for the Congressional Budget Office. I think they are still done the same way. See lecture 13. Here are some of the things that Blinder had to tell his new research assistant to do.1. Make sure that there were channels in the model for credit market conditions to affect consumption and investment.

2. Correct the model’s past forecast errors, so that it would track the actual behavior of the economy over the past two years exactly. With the appropriate “add factors” or correction factors, the model then produces a “baseline scenario” that matches history and then projects out to the future. For the future, a judgment call has to be made as to how rapidly the add factors should decay. That is mostly a matter of aesthetics.

3. Simulate the model without the fiscal stimulus. This will result in the model’s standard multiplier analysis.

4. Make up an alternative path for what you think would have happened in credit markets without TARP and other extraordinary measures. For example, you might assume that mortgage interest rates would have been one percentage point higher than they actually were.

5. Simulate the model with this alternative scenario for credit market conditions.

6. (4) and (5) together create a fictional scenario of how the economy would have performed had the government not taken steps to fight the crisis. According to the model, this fictional scenario would have been horrid, with unemployment around 15 percent.

In the case of climate, the equivalent fictional scenario would be the world without manmade CO2, but the process of tweaking input variables and assuming one’s conclusions is the same.

  • WaldoWell

    Well Russ,

    Here are the questions you dodged despite being asked twice.

    Why are you dealing with science from the 1980s?

    Why don’t you hold your blog skeptics to the same level of criticism that you hold climate scientists?

    And I only asked this once, but do you hold other predictive disciplines to the same standard that you hold climate science? A question you thoroughly ignored.

    As for Hansen’s early predictions, I ignored nothing. Fine, he made predictions – they were not exact but they have proven essentially sound. The data is there; great, good for you. We differ (and I might point out that I have the science community on my side). What more do you want?

    As for Hansen, I never said he admitted to over-estimating, simply that he believes we have more to learn. I believe it is from one of his op-eds but I am too tired to look for it at the moment. You may if you really must obsess over it more.

    And fine if you want to take your ball and go home in a huff – you are not the first to back away from the tough questions you do not want to answer. But please, look at the list above before you decide you have any moral or intellectual superiority here.

    So…C’ya.

  • mglfnafh

    “Fine, he made predictions – they were not exact but they have proven essentially sound.”

    No, they haven’t. They weren’t even close.

  • Wally

    “I think the term “denialist” is apt. Please don’t take it personally. ”

    And I think the term “idiot” is appropriate of you, but hey, don’t take it personally!

  • Steve A Morris

    Very good analogy. It didn’t escape me that Macroeconomics and Anthropogenic Global Warming are little different in nature, at least with regards on how their advocates present them. It’s the same people who fall for both.

    Given this, is it hard to imagine why AGW has such a large following? Macro-economists have to run everything thru very complicated algorithms and so do AGW ‘Scientists’. So it becomes more of a PR game on who can convince the most people rather than being able to actually predict anything.

    The general public then has to rely on ‘Trust’. Go to any AGW Advocate site and look for the words ‘trust’, ‘credibility’, ‘consensus’, ‘estimated’, ‘revised’, ‘adjusted’, ‘modest’, ‘alarming’, ‘likely’, and the list goes on an on.

    Find another Theory that relies on such a myriad of subjective terms, and you have found us a Theory that holds no water.

  • netdr2

    Did not post on CS.

  • netdr2

    So Waldo it all boils down to ” trust us we are professionals”. No one else can read a graph can they ?
    Don’t trust your own analysis because you can’t possibly interpret a graph.
    .
    Even when the professionals models fail to predict the future and only predict the past because they are adjusted until they do.

    .
    Arguably, the most famous model prediction is Dr Hansen’s 1988 graph of expected warming which isn’t doing very well as of 2009. [We don’t know about 2010 yet.]
    .
    You don’t have to be a climatologist to see that reality didn’t match the prediction. Oh I forgot you DO have to be a trained climatologist to read a graph.
    .
    Here is a graph from Dr Hansen’s 2005 defense of his model.
    .
    http://cstpr.colorado.edu/prometheus/archives/hansenscenarios.png
    .
    Here is the prediction itself. See page 7.
    .
    http://pubs.giss.nasa.gov/docs/1988/1988_Hansen_etal.pdf
    .
    As of 2005 he was doing pretty well, but the value of the anomaly as of 2009 is .57 ° C which puts it below scenario “C”.
    .
    http://data.giss.nasa.gov/gistemp/graphs/Fig.A2.txt
    .
    Even using the UHI polluted data of GISS which is obviously too high he didn’t do well. My OUIJA board could do better !
    .
    Scenario “C” was what would be expected if massive carbon restrictions were put in place in 1988 which didn’t happen did it ?
    .
    Did any model predict the lack of warming from 1998 to 2009 ?
    .
    If it did it was hushed up and hidden from the public because it didn’t fit the agenda of the climate alarmists. The scientists whispered his results into a closet when no one was listening.
    .
    This one was used to extort huge amounts of funds from congress !
    .
    I believe the manipulation of the surface temperature data is to rescue this and other such models from utter disgrace. Who put the fox in charge of the hen house ?
    .
    Comparing a climate alarmist scientist to a doctor is insulting to the doctor. If a doctor is wrong he buries his mistake and if he is wrong long often enough he is forced out of the profession. A climate alarmist can be wrong for 30 to 50 years and be hailed as a near rock star. Someday one will be given a Nobel prize like Al Gore.

  • netdr2

    So Waldo it all boils down to ” trust us we are professionals”. No one else can read a graph can they ?
    Don’t trust your own analysis because you can’t possibly interpret a graph.
    .
    Even when the professionals models fail to predict the future and only predict the past because they are adjusted until they do.

    .
    Arguably, the most famous model prediction is Dr Hansen’s 1988 graph of expected warming which isn’t doing very well as of 2009. [We don’t know about 2010 yet.]
    .
    You don’t have to be a climatologist to see that reality didn’t match the prediction. Oh I forgot you DO have to be a trained climatologist to read a graph.
    .
    Here is a graph from Dr Hansen’s 2005 defense of his model.
    .
    http://cstpr.colorado.edu/prometheus/archives/hansenscenarios.png
    .
    Here is the prediction itself. See page 7.
    .
    http://pubs.giss.nasa.gov/docs/1988/1988_Hansen_etal.pdf
    .
    As of 2005 he was doing pretty well, but the value of the anomaly as of 2009 is .57 ° C which puts it below scenario “C”.
    .
    http://data.giss.nasa.gov/gistemp/graphs/Fig.A2.txt
    .
    Even using the UHI polluted data of GISS which is obviously too high he didn’t do well. My OUIJA board could do better !
    .
    Scenario “C” was what would be expected if massive carbon restrictions were put in place in 1988 which didn’t happen did it ?
    .

    Comparing a climate alarmist scientist to a doctor is insulting to the doctor. If a doctor is wrong he buries his mistake and if he is wrong long often enough he is forced out of the profession. A climate alarmist can be wrong for 30 to 50 years and be hailed as a near rock star. Someday one will be given a Nobel prize like Al Gore.

  • netdr3

    Did any model predict the lack of warming from 1998 to 2009 ?
    .
    If it did it was hushed up and hidden from the public because it didn’t fit the agenda of the climate alarmists. The scientists whispered his results into a closet when no one was listening.
    .
    This one was used to extort huge amounts of funds from congress !
    .
    I believe the manipulation of the surface temperature data is to rescue this and other such models from utter disgrace. Who put the fox in charge of the hen house ?
    .