Jensen Effect on c^2 in Rijsdijk et al.

I repeated the previous analysis using the Dutch Twin study data provided by Rijsdijk et al. I extracted g-loadings from the correlation matrices using:

MATRIX DATA VARIABLES=ROWTYPE_ INF COM ARI SIM DS VOC CODE PC BLK PA OA Raven.
BEGIN DATA
N 200 200 200 200 200 200 200 200 200 200 200 200
CORR 1
CORR 0.55 1
CORR 0.52 0.48 1
CORR 0.55 0.59 0.53 1
CORR 0.39 0.34 0.46 0.38 1
CORR 0.67 0.66 0.56 0.67 0.43 1
CORR 0.21 0.16 0.26 0.14 0.29 0.21 1
CORR 0.30 0.39 0.30 0.31 0.20 0.34 0.22 1
CORR 0.35 0.31 0.47 0.36 0.29 0.34 0.19 0.30 1
CORR 0.28 0.36 0.29 0.33 0.21 0.32 0.08 0.33 0.32 1
CORR 0.20 0.25 0.25 0.25 0.08 0.21 0.07 0.28 0.49 0.26 1
CORR 0.49 0.47 0.51 0.47 0.38 0.51 0.25 0.31 0.40 0.32 0.25 1

END DATA.
factor /matrix=in(cor=*).

The results are below:

Jensen Effects based on Rijsdijk 2002

And the results of all three analyses done so far are as below:

Jensen Effect on c^2 summary

The last column presents a corrected estimated of the shared environment – g-loading correlation. Since it has been found by psychometric meta-analysis that the r between heritability and g-loading is 1, and since the average correlation found in these studies was 0.62, it was assumed that the shared environment – g-loading correlations were attenuated. To correct for this, these correlations were divided by the heritability – g-loading r and then averaged. The averaged, k=3, corrected correlation came out to 0.36. This would be relative to a corrected h^2 – g-loading correlation of 1 and a corrected ethnic groups difference g-loading correlation of 0.82.

Obviously, I think that at least half a dozen studies are needed before it becomes even worth discussing the implications of the relation between c^2 and g-loadings for this or that.

References:

Rijsdijk, F. V., Vernon, P. A., & Boomsma, D. I. (2002). Application of hierarchical genetic models to Raven and WAIS subtests: a Dutch twin study. Behavior Genetics, 32(3), 199-210.

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