Looking for Flynn effects in a recent online U.S. adult sample: Examining shifts within the SAPA Project

This is an heroic study. It tackles a very difficult question: Are average IQ levels rising or falling?

IQ is under heavy genetic influence so, given the slow rate of human evolution, we should not expect to see much change over the last 100 years or so. And for a long time that was assumed. WHEN scores were collected was not much attended to. Jim Flynn, however upset the applecart by noting that average IQ levels seemed to be rising. So: Are we really getting smarter on average?

There has now been a lot of research and discussion on that question, ably summarized in the article below. It is a strongly held view among many researchers that the gains are artifactual -- i.e. not real. In particular it is well accepted that performance on paper and pencil tests is influenced to some extent by non-genetic influences -- education in particulr.

IQ scores increase markedly in line with better educational performance so improved education might be what is showing up in improved IQ scores. Levels of education have increased markedly over the years. Jobs that once needed an apprenticeship only now need an university degree -- e.g. primary school teaching.

I must say that I have noted that in my own family. My grandfather never went to school; my father got only as far as 6th grade while I have a doctorate. So generational differences in education are certainly available as an explanation of education-linked effects.

So the rises in average IQ scores observed by Flynn need no complex explanation. And their recent levelling off could well indicate that the maximum effect of education on IQ scores has now been reached

The article below does however put the cat amomng the pigeons. It says that average levels of IQ are now FALLING

I don't find that surprising. The Leftist influence on education is now strong. And it is in many cases a very negative influence. So we now have the politics of mathematics for example, which is as nutty as you get. And university graduates who can barely read and write are now a thing. And there is even suggestion that learning or not learning cursive handwriting has an effect on IQ

So the Leftist destruction of traditional education could well be reflectd in recent IQ scores. Education giveth and education taketh away.

We have to restrain our enthusiasm about the study below, however. It is a study of responses from internet volunteers. And it is perfectly clear that the sample is not a representative one. Just the gender imbalance noted shows that.

Such samples are now widely used in survey reseach and the imbalances in them can theoretically be corrected for statistically -- but how do you correct for enthuiasm/boredom and the many other influences that motivate the answering of internet questionnaires? It cannot be done. There is no substitute for actual random sampling of a specified population.

There is in fact no completely randown sample of any human population. I have tried many methods so the failings are well-known to me. Even compelled responding -- as with army recruits -- is imperfect. Some respondents will resent the task and not give useful answers. I have looked with sorrow at patterns of zig-ag and all-agree responses to my questionnaires from military recruits.

So the best we can hope for is COMPARABLE sampling and it is clear that internet sampling is not comparable to the pencil and paper responses in school-rooms that is most of the data on IQ scores from the past

Elizabeth M. Dworak et al.


Compared to European countries, research is limited regarding if the Flynn effect, or its reversal, is a current phenomenon in the United States. Though recent research on the United States suggests that a Flynn effect could still be present, or partially present, among child and adolescent samples, few studies have explored differences of cognitive ability scores among US adults. Thirteen years of cross-sectional data from a subsample of adults (n = 394,378) were obtained from the Synthetic Aperture Personality Assessment Project (SAPA Project) to examine if cognitive ability scores changed within the United States from 2006 to 2018. Responses to an overlapping set of 35 (collected 2006–2018) and 60 (collected 2011–2018) items from the open-source multiple choice intelligence assessment International Cognitive Ability Resource (ICAR) were used to examine the trends in standardized average composite cognitive ability scores and domain scores of matrix reasoning, letter and number series, verbal reasoning, and three-dimensional rotation. Composite ability scores from 35 items and domain scores (matrix reasoning; letter and number series) showed a pattern consistent with a reversed Flynn effect from 2006 to 2018 when stratified across age, education, or gender. Slopes for verbal reasoning scores, however, failed to meet or exceed an annual threshold of |0.02| SD. A reversed Flynn effect was also present from 2011 to 2018 for composite ability scores from 60 items across age, education, and gender. Despite declining scores across age and demographics in other domains of cognitive ability, three-dimensional rotation scores showed evidence of a Flynn effect with the largest slopes occurring across age stratified regressions.


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