Saturday, August 23, 2014

Monkey Cage Match

A real smack down in the Monkey Cage via Jonathan Bernstein (who summarized better than I can)

A catch to Andrew Gelman for correcting an attempted but inaccurate catch by Alfred Moore, Joseph Parent and Joseph Uscinski, who thought they had caught Paul Krugman in an error on the always-fun topic of conspiracy theories. Not so!

I cut and paste from Gelman

More particularly, Moore et al. criticize liberal pundit Paul Krugman for writing, “Unlike the crazy conspiracy theories of the left — which do exist, but are supported only by a tiny fringe — the crazy conspiracy theories of the right are supported by important people: powerful politicians, television personalities with large audiences.” They respond, “Krugman is mostly wrong that nuttiness is found mainly among conservatives.” But that’s not what Krugman wrote!
This shows, among other things, the power of Krugman derangement syndrome -- people often right that his claim is refuted because of a fact noted in the criticized post.

I think there is a simple solution to the Moore et al etc problem. I think there should be an editorial rule that if one criticizes another for exaggerating (say Al Gore inventing the internet) oversimplifying or omitting inconvenient facts, then one is not allowed to paraphrase.

If Moore et al had been required to use only direct quotes of Krugman, their elision of his statement of exactly the fact which they claim contradicted his statement would have been obvious.

What's the problem even with the stronger rule that one must quote directly and only quote directly when one criticizes ? Would we run out of pixels ? I think the rule should be cut and paste and if you insist elide but don't ever paraphrase when criticizing.

This is now the editorial policy of this blog (catch me in comments and you will get the fame that comes when your comment is pulled back to the main window of a 50 hits a day blog).

I also wrote a comment which notes that we will obtain objectivity no sooner than nirvana, immortality and a pony.

My comment.

Excellent post.

I noticed something funny -- the figure from Kahan Peters et al (2012) doesn't illustrate your point well at all. You write "the research of Dan Kahan finding that roughly equal proportions of political liberals and conservatives in the United States engaged in irrational or “motivated” reasoning" but there is no evidence related to that issue in the figure.

In fact, the data for liberals happens to correspond exactly to the arbitrary hand drawn illustration of unmotivated reasoning with bounded rationality. Now I do not think that Kahan et al provide any evidence that liberals do not engage in motivated reasoning or even that liberals engage in it less than conservatives. The figure illustrates the prejudice of the person who made it based on Kahan et al 2012 [note in the comment over there I mistakenly asserted that the figure is in the published article -- I don't know who made it] prejudices (I guess based on it that he or she is a liberal who thinks that Climate change is a big risk).

My point (if any) is that one can't tell if reasoning is motivated without knowing the consequences of unmotivated reasoning. As far as I can imagine, we could only tell how vulnerable someone is to motivated reasoning if we were capable of perfect objectivity.

Teh figure could be explained if a hypothetical perfectly objective and well informed agent would answer 8 and liberals are completely immune to ideological reasoning, and equally well explained if that hypothetical agent would say 3 and conservatives were completely immune to ideological reasoning.

Until we achieve perfect rationality ourselves, we can't measure the irrationality of others. That is, I think your claim couldn't possibly be have been demonstrated scientifically given data available in 2014 AD or 1002014 AD.

I had some more pointless text here &ran out of allowed characters exactly when I tried to type "conservatives were completely immune to ideological reasoning." I figured it out (& can explain with my 90 left) but irrationally guessed ideological typos or bugs or something.

Tuesday, August 12, 2014

Copying It's not Just for Students any More

There is alleged to be a problem with students taking exams and knowledge spillovers. Another question is whether grownups do this too. Yes they do. In a totally brilliant post building on brilliant research by Joshua Clinton and Steven Rogers (pdf warning)

I comment

Brilliant. One obvious practical question is whether one gets better forecasts by averaging only gold standard polls (if any are available). Do the non traditional polls improve or worsen the average ? A purely hypothetical purely copycat pollster who took an average of other polls then added a bit of noise to disquise the purely hypothetical (non-irony alert really) would worsen the average.

Anyway a set of simple practical questions are of the form If there are N gold standard polls, the average of the N gold standard polls gives a lower forecast error than the average over all polls. Arithmetic says this can't be true if N is zero. I doubt it would be true if N is 1. It might not be true for any N (averaging is powerful and the purely hypothetical fraudulent pollster doesn't exist). So I ask when is N enough ?

Now I also think that forecasters would do better if they were to copy more, but this doesn't mean that averages would be better if forecasters were to copy more.

There is a real problem. Note that the purely hypothetical pollster might have low forecast errors. The simple trick that averaging improves forecasts, makes it possible to make good forecasts which don't contribute anything to the accuracy of the average. In the real world, pollsters who fiddle the numbers to make their results closer to the lagged average will have lower forecast errors than those who don't even if averaging them in improves forecasts less.

Tuesday, August 05, 2014

Paul Krugman has an unanswered question

Paul Krugman wrote
The answer all the deficit-panic types offer is basically that we must cut future benefits. But why, exactly, is that something that must be done immediately? If you state the supposed logic, it seems to be that to avoid future benefit cuts, we must cut future benefits. I’ve asked for further clarification many times, and never gotten it.
I am not a deficit-panic type demanding immediate cuts to future benefits, so I can't answer the question. That won't stop me from trying. I can think of three answers. The first is not

0) "Greece Greece I tell you." Krugman understands this argument. In fact I am quoting him putting words in the mouth of a straw man. He once believed something like the non parody version of this. This is one of the errors he pulls out when he is accused of not admitting errors. The short reply is "Japan Japan I tell you." The long one is to ask people to explain how the USA could run out of dollars. Greece can go bankrupt because it borrowed in Euros. California can and Argentina did default because they borrowed in dollars. The US Federal government can't run out of dollars. The true concern isn't for the debtor (US Treasury) but the creditors who don't want the value of their dollar denominated assets to be inflated away.

1) We must cut benefits now, because if we don't we won't cut benefits later (I favor this one). It is hard to cut future social security and Medicare benefits but it is essentially impossible to cut current benefits. If the USA reaches the point where the can can't be kicked down the road, taxes will be increased. My guess is that programs with dedicated revenue streams and trust funds will just continue if the trust fund reaches zero, with the general fund paying part of the cost. The fear of the deficit hawks is the so called bankruptcy won't amount to anything and things will just continue until investors loose confidence in Treasury securities. Even if something is then done, it will include tax increases and probably soak the rich type tax increases.

In contrast they might hope to legislate cuts in future benefits for the currently non-elderly. This means the argument cut future benefits now to avoid cutting them in the future is indefensible, because it is insincere. If the aim is to cut benefits rather than raise taxes on the rich, honesty is not the best policy. The argument that an empty trust fund will be like say Lehman going bankrupt and not like Social Security before the Greenspan commission is needed to convince people to accept distant future benefit cuts which they prefer to sharp emergency benefit cuts, but which they like less than current or future planned or emergency tax increases on high incomes.

2) Unfortunately, it might just be me first listen to me first nowwwww. If one's expertise is in long term budget forecasting, the frank statement that one knows about a problem which doesn't need immediate attention is a sure way to be ignored. No one likes the prospect of waiting 20 years before anyone will listen. Everyone argues we should listen to them now.

But I like explanation 1) better. I think it is about taxes on the rich, because it is generally about taxes on the rich.

Friday, August 01, 2014

Experiment in Information Retrieval, Moore's law and double or nothing betting.

How hard is it to get state employment data ? I want past 5 years (told goes through May). I go to What a pain. 10 minutes and raw data on my hard disk. I had to check I am doing seasonally unadjusted to seasonally unadjusted. I have a *.txt file. Now states are Texas, California, New York and Florida. All data in thousands data Texas May 2009 10,399.3 May 2014 11,562.5 difference 1,163.2 California May 2009 14,351.5 May 2014 15,487.2 difference 1,135.7 New York May 2009 8,605.2 May 2014 9,057.3 difference 452.1 Florida May 2009 7,399.3 May 2014 7,801.8 402.5 23 minutes in all data here, but I have to subtract. Twenty three Minutessss !!! is it me or is the BLS site a nightmare ? It's me it is now 25 minutes in and all I did was subtract 3 numbers from 3 numbers (I had done Texas) OK so 25 minutes to answer from what the hell is this BLS web site. I am sure it would have been quicker with FRED.