I just came across a book with the promising title „Street-Fighting Mathematics — The Art of Educated Guessing and Opportunistic Problem Solving“ by Sanjoy Mahajan (2010), which is actually licensed under Creative Commons, so it can be found for free online. The basic premise is to provide some mathematical tools or heuristics to sufficiently approximate solutions to everyday problems (and maybe also provide a more general framework for that kind of reasoning). And it starts teasingly with a topic called „Dimensions“ and „The power of multinational corporations“. Here’s the problem:

In Nigeria, a relatively economically strong country, the GDP [gross domestic product] is $99 billion. The net worth of Exxon is $119 billion. “When multinationals have a net worth higher than the GDP of the country in which they operate, what kind of power relationship are we talking about?” asks Laura Morosini.

What is the most egregious fault in the comparison between Exxon and Nigeria?

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In his „Comments on the State of Psychotherapy Research (As I See It)“ David Orlinsky points to some old wounds in psychotherapy research (and in many ways research in psychology in general). I think it is worth re-reading every now and then while you are active in the field. Right now I discovered some stimulating words on the „Placebo Effect“, something I feel will be important to really understand and utilize in practice in the next decade. Unless we want to leave it to modern shamans of good and bad intentions.

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Granted that Google has grown into a controversial giant, with a grip on our personal data and lives so firm that a skeptic watchfulness seems in place. They do stay in front of a digital revolution that often serves the common good as well as their own. The latest trick has the magic name „N-Grams“, refering to combinations of N words, starting with single words. The idea is to use the scanned Google Books database to count the frequency of words over time. The data is available freely, both for download to be used in „serious“ statistical analysis, and in an easy online tool.

A NYTimes article points to an example comparing the appearance of „men“ and „women“ and supposedly showing a „feminism bump“ in the 1970s. The German newspaper ZEIT twittered a history of nuclear energy and the nuclear waste debate.

Of course, this entry of an abundance of numbers into classical research domains of the humanities is controversial, as the NYTimes reports. The founders are aiming high:

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Wie gut, dass die ZEIT in der Serie „Stimmt’s“ nach und nach mit den Überzeugungen aufräumt, die unseren Alltag steuern und oft genug einschränken.

Und wer wurde noch nicht beim Anblick verlockender Beeren auf einer Wanderung von wohlmeinenden Freunden vor dem Fuchsbandwurm gewarnt? Zu Unrecht. Zwar ist die Infektion mit dem Fuchsbandwurm wirklich gefährlich. Aber es gab 2008 nur 26 Fälle in Deutschland. Und die haben sehr wahrscheinlich nichts mit Beeren zu tun:

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Ich hoffe, dass die Nachrichten über diese Sache bald ein Ende haben — nachdem ich schon vor drei Jahren darüber gelesen habe bin ich wohl sensibilisiert, und stolpere immer wieder über einen Artikel. Nachdem sich am Beispiel Bisphenol A sehr gut die Gefahren von industriefinanzierten wissenschaftlichen Studien zeigen ließen, und in den USA die Regulierung voranschritt, liefert die Substanz jetzt den Anlass für einen Artikel in der ZEIT über die Verquickung der EU-Lebensmittelbehörde EFSA mit der Industrie. Viele Mitglieder sind gleichzeitig einer Organisation der Chemie– und Lebensmittelindustrie. Entsprechend lax fallen ihre Regulierungen aus:

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In einem ZEIT Interview, das sich nur knapp explizit auf Sarrazin bezieht, aber trotzdem sicherlich in die mit ihm explodierte Diskussion einzuordnen ist, bezieht ein Berliner Historiker und Antisemitismus-Experte seine Erkenntnisse auf den heutigen Umgang mit Minderheiten, vor allem Muslimen. Spannend! Er spricht mir aus der Seele, wenn er fordert, historische Forschungserkenntnisse für die Gegenwart relevant zu machen:

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I wouldn’t usually like to end a post title with a question mark — it does remind me of yellow press. But what else can I do writing about a book I haven’t read myself?

Judging from a NYTimes book review of „Disconnect“ by Devra Davis, though, the German radiation paranoia might turn out to be quite sensible. To put it cautiously: It is at least scientifically plausible that cell phone usage (i.e. holding it to your head while speaking) is linked to brain cancer:

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Wie die ZEIT berichtet ging gerade ein großer Feldtest mit Elektroautos von BMW (in Gestalt des Mini-E) zu Ende. Die Erprobung sei fast schon überraschend positiv verlaufen, so haben sich die Testfahrer selbst ohne die für die Zukunft vorgesehene Elektro-Infrastruktur kaum eingeschränkt gefühlt. Allerdings war das Elektroauto oft Zweitwagen, und die Erprobung lief in großen Städten. Zu kaufen soll das erste Serienauto mit Elektroantrieb schon 2013 sein.

The good old Sarrazin debate taking place in my room this morning made me search for some scientific publications on the issue myself. I found one highly cited paper that seems to lay out the situation quite clearly:

Studies of correlations among twins or adoptees and their biological and adoptive parents typically yield large genetic effects and relatively smaller effects of family environment, whereas studies that compare the mean IQs of children rescued from poverty with the IQs of their parents or impoverished siblings often find large differences that are attributed to the environment (Turkheimer, 1991).

So what Sarrazin quotes in terms of high heritability is only half of the truth. How can these disparate findings be unified? Here is the hypothesis that was confirmed in the study:

One possible resolution of this paradox is that the effect of family environment on cognitive ability could be nonlinear (Jensen, 1981; Scarr, 1981). If differences between impoverished environments and adequate ones have large consequences for cognitive ability, but differences between adequate and enriched environments do not, one would expect amelioration of impoverished status to show a substantial effect, whereas correlational findings based on middle-class family members in typical twin and adoption studies would not.

In a way (as has been rightfully pointed out for the debate as a whole) this is just elaborating on what has been said on differences in IQ between groups before: A certain degree of heritability within a group says close to nothing about the genetic differences between groups. The quoted article just shows how this applies to socioeconomic groups as well es ethnic groups, which had been a central issue in the similar debate in the US some 15 years ago.

Which makes Sarrazins point (Germany is threatened by an increase in proportion of genetically less intelligent individuals due to different rates of reproduction between socio-economic groups) scientifically implausible on top of what it has been from the beginning: politically and morally tasteless and neglecting of the historic dimension and practical implications of trying to change the genetic composition of society.

Apart from that, I think it is useful to point out an old misunderstanding with the theory of evolution: One naively tends to conclude that evolution must favor intelligence, and that the „natural“ way of things should be for intelligent people to procreate more. This would make the (assumed) opposite direction of „evolutionary shift“ due to the way our society is structured „unnatural“ and imply that it is wrong (which is itself a moral-philosophic misunderstanding called the Naturalistic Fallacy). However, the fact that there still are genetically more and less intelligent (one should say: predisposed to developing intelligence) people around proves that „evolution“ has nothing against them. If one wanted to speculate wildly and freely one could say that „evolution likes them“ precisely for the fact that they procreate more… A remotely similar point has recently been made about sheep with stronger and weaker immune systems and, some years ago, about learning ability in fruit flies.

I have strayed from the topic, but I’m glad I had an opportunity to link to that sheep article in a useful way after all

Mal wieder über Greg Mankiw komme ich zu einem Video, dessen Inhalt eigentlich zu speziell ist, um mich wirklich zu interessieren. Es geht um die Arbeitsmarktentwicklung der USA und darum, welche Politik darauf wie gewirkt hat.

Spannend daran ist, dass auf sehr anschauliche Weise ein ehemaliger Wirtschaftsberater unter George W. Bush die Aussagen kritisiert, die in einem ursprünglichen Video vom derzeitigen Chef des ökonomischen Beratergremiums unter Barack Obama gemacht werden. Die Aussagen werden auf clevere Weise nebeneinander gestellt, und dabei wird sehr schön illustriert, wie wenig Halt leider die von beiden Seiten präsentierten „harten“ Zahlen bieten. Im Video klingt natürlich der Kritiker überzeugend, aber ich bin ziemlich sicher, dass sich dem wiederum überzeugend entgegnen ließe. Gibt es eine „richtige“ Art, Zahlen auszuwählen und zu interpretieren? Und wenn nicht, was dann?

Hier ist jedenfalls das Video:

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