Saturday, 31 August 2013

Poverty and Class, and a mostly missing variable


Courtesy of the British Psychological Society, I was alerted to the recent publication of the Journal of Educational Psychology “Virtual Issue: Research from Educational and Developmental Psychology on Poverty and Class“ Edited by Harriet Tenenbaum.

The editor writes in her introduction: “The first half of the selected articles in this virtual issue focus on relations between income and education and the second set on children’s views of economic inequality. The first set of selected articles address why children from low-income families may do less well in education, but also address interventions designed to improve the education of children from low-income families.” “The studies reported in these articles were conducted in many different countries conforming that the influence of poverty on education is important in countries as egalitarian as Sweden.” “In general, the first set of these articles indicate that income serves as a risk factor for educational attainment (Cassidy and Lynn, 1991) partially because of cultural capital or class reproduction (Myrberg & Rosen, 2009). Other factors, in addition to income, influence school dropout (Fan & Wolters, 2012) and achievement (Cassidy & Lynn, 1991).”

There are 10 articles in all. The first mentions intelligence by name, and shows that it has an influence. It also measures personality. One other (Dockrell, Stuart and King) includes some British Ability Scale subtests, and another (Sylva et al.) includes the British Picture Vocabulary Scale as a measure of literacy and general ability.

So, at very best, out of 10 key papers, chosen to be of above average quality and impact on the theme of poverty and class, 3 mention ability, one of those three explicitly. That first paper provides a good model as to what every educational paper should include: a measure of intelligence (here the Differential Aptitude Test); a measure of personality (here the Junior Eysenck Personality Questionnaire); measures of social class, parental education and occupation, family size, type of school attended, an index of possessions in the home, a home crowding index, a measure of parental encouragement of education; and then the target variable, a 20 item measure of achievement motivation. As you can see, all putative causes get a chance to contribute. This paper by Tony Cassidy and Richard Lynn uses path analysis (in 1991) and concludes:

“This study replicates the findings by Lynn et al. in that school-type, IQ, and home
background are important predictors of educational attainment. School-type is the single most important predictor, accounting for 19.6 per cent of the variance. IQ accounts for 13.1 per cent and the combined home background variables of crowding and parental encouragement account for 18.1 per cent of the variance. The other important direct predictors of educational attainment are the achievement motivation dimensions of acquisitiveness, dominance and work ethic. Among them these variables account for 36.2 per cent of the variance. The total variance accounted for by the variables in this study is 87 per cent.”

However, more important than the results of a particular study done 22 years ago, is that so few of the other, usually far more recent, paper show the same even handed range of variables. Since intelligence precedes schooling, and schooling precedes getting a job, and a job precedes accumulating wealth, one might have expected at least basic measures of intelligence to be found in all these educational papers. Its absence allows the authors to draw conclusions about class, poverty, and educability without intelligence having a chance to be tested as a contributing factor. Most seriously, its absence often leads to thoroughly misleading conclusions. For example, Fan and Wolters measure school dropout without taking any measures of intelligence, a very significant omission. Dockrell, Stuart and King have obtained some measures of intellectual ability, but do not display the relationship between intelligence and learning in their intervention study, which would have been instructive.

The papers in the virtual edition are very probably a fair selection of educational psychology publications. Most of the sample sizes are small,  particularly in relation to the effects being studied, and few are population based. My main gripe is that I do not think that educational psychology papers give a fair place to intelligence assessments (nor to personality measures). It is a pity, and significantly reduces our ability to understand children’s educational progress.


  1. As it happens, long ago I had a bit of contact with educational psychologists. In general they were intellectual duds and, separate point, infused with political bias. The expression "wilful blindness" springs to mind.

    I can remember Mr Blair's new government scrapping a Tory scheme ("assisted places") that paid the fees so that bright children from poor households could attend private schools. I remember one Labour man explaining that too many of the children came from the "wrong sort" of poor household. It turned out that he meant parsons' children, the children of middle-class abandoned wives, and the like.

  2. When I read _The Bell Curve_ back in the nineties, I was surprised at the difference between what the authors thought their main point was and what practically everyone else thought it was. As I recall, according to them, their main point was that social scientists need to control for IQ pretty much all the time because it is essentially always a very important confounder. Obviously, nobody much listened.

  3. The Bell Curve was more salivated at than read. There was also a discussion about the problems which might arise from intellectual elites, particularly as economies required more knowledge workers.