Showing posts with label pseudoscience. Show all posts
Showing posts with label pseudoscience. Show all posts

Sunday, 17 July 2011

Pseudoscience 2


Hung out to dry
  One of the things that I do is save interesting items in my miscellaneous boxs for future reference if something along  the same topic happens to appear. The map above is a comparison of penis size (PS) for various countries from a Chinese newspaper which was only distributed locally and I happened to notice a couple of months ago. The writer of the article whose name I forgot tried to make the argument that PS is negatively correlate with economic growth. I dismissed the analysis at the time because the median length of a penis is genetically determined so you could have used the same map forty years ago when the Chinese cultural revolution was in flower as well as India mired in poverty and reached the opposite conclusion that PS had a positive correlation with GDP growth; however, you can't keep a good supposition down so I kept the map for future reference.

  Imagine my amazement today when I discovered a paper from of all places Finland that had the title," Male Organ and Economic Growth: Does Size Matter?" by Tatu Westling of the University of Helsinki.

Abstract:

This paper explores the link between economic development and penile length between
1960 and 1985. It estimates an augmented Solow model utilizing the Mankiw-Romer-Weil
121 country dataset. The size of male organ is found to have an inverse U-shaped
relationship with the level of GDP in 1985. It can alone explain over 15% of the variation in
GDP. The GDP maximizing size is around 13.5 centimetres, and a collapse in economic
development is identified as the size of male organ exceeds 16 centimetres. Economic
growth between 1960 and 1985 is negatively associated with the size of male organ, and it
alone explains 20% of the variation in GDP growth. With due reservations it is also found
to be more important determinant of GDP growth than country's political regime type.
Controlling for male organ slows convergence and mitigates the negative effect of
population growth on economic development slightly. Although all evidence is suggestive
at this stage, the `male organ hypothesis' put forward here is robust to exhaustive set of
controls and rests on surprisingly strong correlations.

 I have to mention that there is no connection between the Chinese article and the Finnish paper of which I'm aware so two analysts working on opposite sides of  the world have independently arrived at the same conclusion with the addition that the paper also includes temporal data. First I was having some amusing thoughts about how the author of the paper controlled for the male organ - a procrustean bed perhaps?  Secondly both writers eliminated half of the population i.e female as having any effect on GDP. This is pretty sexist. Thirdly as I pointed out in my initial pseudo science post a correlation is not causality.

Getting down to particulars, the paper specifies that the PS was specifically the erect length and I wonder how this was achieved since the paper doesn't go into details and says "taken at face value, the findings suggest that the 'male organ hypothesis' put forward here is quite pentrating an argument. Yet for the best of the author's knowledge, the male organ has not been touched before in the growth literature before." Ok. I know what you're thinking. I'm just quoting verbatim here.

Then we get lots of fancy math, equations and graphs. Regression analysis, augmented Solow model using the Mankiw-Romer-Weil dataset etc. I can do this stuff on any data set and it doesn't add any validity to the fundamental set of assumptions and conclusions. My final conclusion - Pseudo science with a capital P.





Sunday, 3 July 2011

Pseudoscience (1)




  I’ve been putting off post(s) on this topic because I just would like to ignore it but it’s just like a bad toothache that won’t go away and sooner or later you have to deal with it. The reason I’m starting today is a co-authored paper by Assistant Prof. Andreas Madestam, Boccioni University and Assistant Prof. David Yanagizawa-Drottwhich, Harvard Kennedy School which was mentioned in the Harvard Gazette and concludes that taking children to see a Fourth of July parade turns them into Republicans so all you progressives beware this insidious right wing plot to indoctrinate your offspring. You still have time before tomorrow to pack your bags and drive to some left wing commie blue state campground.


Abstract:


Do childhood events shape adult political views and behaviour? This paper investigates the impact of Fourth of July celebrations in the US during childhood on partisanship and participation later in life. Using daily precipitation data to proxy for exogenous variation in participation on Fourth of July as a child, we examine the role of the celebrations for people born in 1920-1990. We find that days without rain on Fourth of July in childhood have lifelong effects. In particular, they shift adult views and behaviour in favour of the Republicans and increase later-life political participation. Our estimates are significant: one Fourth of July without rain before age 18 raises the likelihood of identifying as a Republican by 2 percent and voting for the Republican candidate by 4 percent. It also increases voter turnout by 0.9 percent and boosts political campaign contributions by 3 percent. Taken together, the evidence suggests that important childhood events can have persistent effects on political beliefs and participation and that Fourth of July celebrations in the US affect the nation’s political landscape.



   Among the footnotes is a suggested comparison to “the effect of the Hajj pilgrimage on adult (Muslim) pilgrims attitude, beliefs and practices” and arguments that “July the Fourth and similar public rituals can be rationalized as a common-knowledge generating co-ordinating mechanism that allows people to submit to a social or political authority.” So your kids turn into gun toting fundamentalist fanatics who submit to conservative ideology and only watch Fox news.


 There isn’t enough information in the truncated form of the paper to make a complete analysis but I do have some questions. The authors stated that the effect is in the shape of an inverted U with respect to age. This makes some sense. Children under 5 won’t understand the emotional implications other than an immediate response and teenagers are probably pretty jaded. Let’s say that we are left with 10 Fourth of July events which have maximal effect out of 15 in the study (3-18) Are the effects additive or non linear? The equation given in the paper has eight co variables to control for such things as age cohort, geographical location, race, gender, family income, education etc. What is the degree of imprecision in each variable given that the total imprecision is the sum of the individual imprecision. How do you assign someone to a particular race? Self identification or external assignment? After the authors control for these factors they do a regression analysis to calculate the degree of correlation which they state is statistically significant.


   A correlation is not causality. If you plot the degree of obesity geographically versus the degree of conservatism in the States, there is a strong correlation. You can’t infer that being porky makes you conservative or being conservative makes you fat.


  They don’t distinguish between variables (race, gender, education etc.) that are extraneous and those that are confounding. "An extraneous variable is a variable that MAY compete with the independent variable in explaining the outcome of a study.  A confounding variable (also called a third variable) is an extraneous variable that DOES cause a problem because we know that it DOES have a relationship with the independent and dependent variables. A confounding variable is a variable that systematically varies or influences the independent variable and also influences the dependent variable." The authors state that the co variables are not individually statistically significant and the use of an F-test demonstrates that the co variables are not jointly statistical significant with respect to the effect caused by an assumed and not measured exposure to F. of J. events. Note also that the education and family income variables are current at the time of study and not those existing at the time of the F. of J. events so the time dependency is not accounted for in their data.


  The caveats were not mentioned in media reports. They assumed that the effect on the individuals did not vary with age in their calculations although they stated the response was in an age related inverted U. If the effects were independently calculated for each age, the data was too “noisy” i.e. the imprecision was too high for statistically valid results. They also stated that the degree of adult conservative affiliation was self reported so I would assume that a primary variable had a lot of wiggle room in it which belies all their mathematical cleverness. This is called in stats parlance reactivity. Reactivity is defined as an alteration in performance that occurs as a result of being aware of participating in a study. In other words, reactivity occurs sometimes because research study participants might change their performance because they know they are being observed. You also have interpretative validity. Interpretive validity is present to the degree that the researcher accurately portrays the meanings given by the participants to what is being studied.

  They stated that the study was an investigation into “group identity formation.” (Clarissa – comments?) I would say that I made a very cursory analysis but from the Fox video the paper gives certain parties grist for their viewpoints without the important nuances and caveats which are critical. Given other recent news reports such as the post I gave on the paper, debt gives students higher self esteem, what else is new. It would also be interesting to do a control study in Canada with Canada Day. Is this effect specific to America? I would say that this represents pseudoscience given all the assumptions, variables and methodological approach. Comments?