How to be a Baller

The term Climateball has been gaining in popularity recently, with a number of people being labeled Climateballers. Like many newish terms, it’s not entirely clear how the word should be used. To help people out, I’m going to discuss an example of how one can be a Climateballer. You should begin by saying something like user KR said:

their ‘red-noise’ model is absurd, given that they didn’t detrend the proxies first (leaving hockey-stickiness in the ‘noise’), and having utterly absurd persistence in their noise, leading to non-stationary series. Fail.

Which was said more simply by user Kevin O’Neill:

M&M contaminated their “persistent red noise” by not detrending the proxy data.

Don’t let the terminology frighten you. The complaint is quite simple. Steve McIntyre and Ross McKitrick generated random series to use as input for a methodology to see what the results would be. Fully random series are called “white.” “Red” series are series where one data point affects the value of the next. That is, in red noise, how high your second point is depends partially on how high your first point is.

The complaint is regarding how “red” the test series should be. When generated red series, you have to decide how strong an effect each point should have on other, nearby points. MM decided to emulate the redness of a set of pre-existing series. The idea was to give their test series the same amount of noise as the series they were comparing to.

The complaint expressed by KR and Kevin O’Neill above is they feel you can’t measure the “redness” of a series which has a genuine signal in it without removing the signal first. They say attempting to results in your test series being “contaminated” by the signal.

Now, being a Climateballer takes far more than making a simple complaint like that. To understand, we’ll need to consider a second complaint posted by KR:

McIntyre and McKitrick did not apply standard significance tests, kept only two PCs, and threw the hockey-stick in the significant PC4 away. This is a basic error in PCA on their part.

This is about a somewhat different topic. The test series created by MM were created to show a methodology used by Michael Mann was biased toward cherry-picking hockey sticks. The idea was to show the methodology, a faulty implementation of principal component analysis (PCA), tended select hockey sticks as its PC1. PCs, or principal components, are the output of PCA. They are ranked according to how important they are, with PC1 being the most important.

MM argue when you use a correct version of PCA, rather than the faulty one used by Michael Mann, you don’t tend to get hockey sticks in PC1 (with the real or test data). KR accepts that but argues when using the correct version of PCA, MM ought to include PC4, which does have a hockey stick shape, even though it is only the fourth most important PC. He claims this is based upon “standard significance tests.”

This is where one can begin to be a baller. KR’s comments got a sarcastic response which quoted a source (which KR calls an “[e]xcellent reference), as saying:

FIGURE 1.
Comparison of eigenvalue spectrum resulting from a Principal Components Analysis (PCA) of the 70 North American ITRDB data used by Mann et al (1998) back to AD 1400 based on Mann et al (1998) centering/normalization convention (blue circles) and MM centering/normalization convention (red crosses). Shown also is the null distribution based on Monte Carlo simulations with 70 independent red noise series of the same length and same lag-one autocorrelation structure as the actual ITRDB data using the respective centering and normalization conventions (blue curve for MBH98 convention, red curve for MM convention). In the former case, 2 (or perhaps 3) eigenvalues are distinct from the noise eigenvalue continuum. In the latter case, 5 (or perhaps 6) eigenvalues are distinct from the noise eigenvalue continuum.

KR apparently missed the point of this quote being provideddespite the sarcastic commentary which framed the quote:

Indeed. McIntyre and McKitrick should have done what Michael Mann did and used an objective rule to calculate how many PCs to keep. Then they would have had to post:

Where they’d be criticized for estimating red noise parameters from tree ring networks without detrending first.

To explain, the excellent reference KR likes so much shows Michael Mann performing Monte Carlo simulations where he created many red noise series with the same autocorrelation structure as the actual data. There’s no mention of him having detrended the actual data first. In other words, he did the same thing McIntyre and McKitrick did (though the exact details of his red noise models are somewhat different).

And that’s how KR shows himself to be a Climateballer. He sees a post showing Michael Mann did something, and he calls it excellent. He sees McIntyre and McKitrick doing the same thing, and he calls it “absurd.”

It gets better though. The paper KR criticizes was published in 2005. The post I quote Michael Mann from was published in 2004. That means Mann not only did the same thing McIntyre and McKitrick did, he did it first. In fact, contemporary commentary at the time shows McIntyre and McKitrick did what they did because Mann did it first. Referencing material in the excellent source KR is fond of, McIntyre said:

We had seen this diagram and calculation in August 2004 and had fully considered it in our GRL submission – in fact, it contributed to the approach taken in our GRL submission, which differs substantially from our previous Nature submission.

So Michael Mann creates test series by using the autocorrelation structure of the actual data without detrending. McIntyre and McKitrick respond by doing the same thing. KR thinks that means McIntyre and McKitrick are horrible people who don’t know what they’re doing. He doesn’t have a problem with Mann though.

And that is how he proves himself to be a Climateballer. It’s not hard. You can do the same. Many others have.


It’s worth pointing the link to that contemporary commentary also shows Michael Mann did not use the rule he claimed to have used. In fact, more recent work strongly suggests there is no “standard significance tests” which could possibly justify the decisions Mann made about how many PCs to use.

Even if that weren’t true, the rule Mann claims to have used, Preisendorfer’s Rule N, is only one of nearly a dozen rules Preisendorfer created. Other people have created more rules. There is no way to say one rule is “right.”

(See here for far more detail about principal component analysis and the selection rules for it than you would likely ever want.)

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14 comments

  1. With regard to the suffix “baller”, isn’t this an allusion to the movie “MoneyBall”

    http://www.imdb.com/title/tt1210166/

    which involved a dogged minority of baseball coaches who used otherwise distrusted computer models to get
    their results?

    If so then a (Foo)Baller is someone who insists on (persists in ?) using computer models for his Foo work, regardless of the real world feedback, yes?

  2. I don’t believe so Pouncer. The word “baller” has been used as slang for as long as I can remember. Climateball comes from Calvinball. I don’t think either uas any connection to that movie. I think it’s just coincidence (the -ball suffix is appended to quite a few things).

    It’s probably just as well. I think the guys were successful in that movie.

  3. Thanks for the concise definition of the situation, succinct but clear. AFAIK, a “baller” is someone who has a good chance to get his date to “put out”. The reference being that the agenda affects the content? 😉

  4. You know there was a book before the movie? It really just focused on the Oakland As management, not the coaches. After the fact, the book doesn’t hold up as well. One entertaining scene is where they have all their advanced stats for measuring players, and the people they draft over several rounds they valued as being in their top 40 overall. Getting a Top 40 player in the fifth round of a 30 team draft is incredible. Now, we see that none of their players were any good except for Nick Swisher.

  5. HaroldW, indeed. That’s fluidity is why it is “absurd” to respond to Michael Mann’s calculations by performing the same type of experiment.

    eqibno, you’re welcome! I’ve actually been exposed to three different meanings of “baller” in my life. The most common was, “Someone who plays basketball.” The second most common was, “Someone who has lots of money and is showy about it.” That one is a spin-off from the first. There were basketball players who were called ballers who made it big and kept getting called ballers. Because they wound up being extravagant with all the money they made, the meaning of “baller” became associated with that. Another one I’ve heard, only rarely, is an alternative for “bawler,” as in a cry baby. I’m not sure any of them really apply to this situation.

    MikeN, I think I had heard something to that effect, but I didn’t pay any attention to the subject. I have a hard time watching things which are supposed to be based on reality (including documentaries). Whenever I watch one on a subject I know well, I see tons of problems. I have to assume that’ll be true for ones on subjects I don’t know well, and it bothers me I won’t be able to spot the problems.

  6. I’m cross-posting a comment I just posted on an older thread because it is relevant:

    Oh lord. I just tried looking for your comment Carrick, and one of the first I skimmed through had this remark by KR:

    AndyL – The Tiljander sediments were discussed as a potential issue in MBH, the bristlecones were an acceptable (although discussed) proxy at the time and have been further validated since then. Again, you are shot-gunning nonsense.

    Donald Graybill, the guy who collected the bristlecone data, specifically warned we couldn’t tell if they were appropriate for use as a temperature proxy. KR says they “were an acceptable… proxy at the time” despite this, offering no explanation why Graybill’s concerns were unjustified.

    The NAS panel specifically said bristlecones should be avoided in temperature reconstructions. KR says they “have been further validated since then” without explaining why specific warnings against using the data “validated” them.

    I’m getting the impression KR thinks anything which gives an answer he likes “validates” his answer.

  7. Reading this term at CA, I thought it might be related to the term spitball, or spitballing as it relates to the special topic of climate – i.e. Nic Stokes is spitballing. Just shooting things out to see if anything will stick.

  8. Gary, as far as I know, willard is the one who first used “Climateball.” Someone may have done it before him though. I didn’t pay much attention to the term until it started catching on more.

  9. Thank you! I was trying to find a definition in Webster but I will go with the Calvinball reference. Would one of the earlier commenters atempt a Webster variant? At this point I would define it as, “a knowledge person (internet troll) who performs the equlivant of yelling “squirrel” in a dog park” . This prevents the untrained (me) from reading the truth.

    The MM reference might seem disrespectful to Steamboat Willie and his creator; however, it fits the slang definition of “Mickey Mouse”.

    It is too bad that the Internet doesn’t allow the bloggers to limit trolls to one comment an article.

  10. CC Reader, you can actually place any limits you want on comments if you’re willing to do some work (and self-host your blog). The problem is more in how you determine who is a troll. People almost never agree on those determinations.

  11. I do not know the intricacies of blog hosting; however, let me give an example of how the problem of Internet trolls could be handled.

    Troll Database:
    Internet Troll Name = Y
    Today’s Date= TD

    Name on today’s blog entry = X

    IF X = Y
    and TD /= TD
    then post comment
    and fill TD with TD
    Send message ” you will not be able to post anymore.
    today.”

    Else Trash entry

    If this could be implemented, it would allow some individuals to post their initial comments but prevent internet trolls from taking over a post. In addition it could/should include a check for banned individuals. If nothing else it would make them choose their arguments wisely and would save moderator time.

  12. CC Reader, it’s easy to implement something like that if you self-host. If you host with WordPress though, you can’t do it. WordPress doesn’t let you add plug-ins or change the code.

    I think lucia (of The Blackboard) actually has code written to do something like that.

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