East End girls

This is something of an accidental blog post.  We were asked recently for some information about young people, which I misinterpreted as asking about differences between local authorities.

One difference between local authorities which has long intrigued me is how different are males and females -- and whether if, in some local authorities, they are more equal.  So, we have known for a long while that self-esteem scores are different between males and females, where males score a little higher than females.  From the more than 7000 year 10 students in our 2017 data bank, we see males scoring an average of 13.4 (on a scale from 0 to 18) while females score 11.9 -- a difference of 1.5 points.  If we use the standardized difference between means as our effect size (Cohen's d), we have an effect size of sex on self-esteem of 0.45, which Cohen would describe as a medium-sized effect.

But the difference, and the effect size, is not the same across the country.  The smallest effect size we see in any local authority is 0.13 (a small effect) while the largest is 0.74, which is quite a large effect.

On a chart, it looks like this:

The overall figures for the whole sample of 7000 are shown as 'All'; the figures for 17 different local authorities A-T are shown in order of effect size, from smallest to largest.  Blue bars show the mean male self-esteem scores; orange bars, the mean scores for females; overall score is shown as a dash; the effect size (Cohen's d) is shown as a line of crosses and is plotted on the right-hand axis. 

[One local authority (K) used a different scale to others, which you can see, but its effect size was quite ordinary.]

Now, wouldn't it be interesting if the areas at one end of the chart all had something in common?  In fact, of the 17 local authorities, 5 were London boroughs; of the four local authorities with the smallest effect sizes, three were London boroughs, while another came in sixth (that is of the six local authorities with the smallest effect sizes, four were London boroughs).