Unlike some people, I'm not impressed by bayesian methods. The bayes factor, so often used and praised by people such as, e.g., Sprenger et al. (

2013) among many others, has the same problem as the p value and other significance tests. The bayes factor is a function of effect size and sample size. The higher the sample size, the greater the difference in "fit" between the models (or hypotheses). In other words : new methods but same problems.

That is a problem similar to CFA-SEM testing hypotheses. Some fit indices are too easily significant, e.g., AIC, BIC, etc. When that happens, a quick look at them and one has the feeling that the two models differ "significantly". But when looking at, e.g., CFI, Mc, ECVI, and RMSEA, one sometimes see that the difference is really small or too small to be of "practical significance".

If one believes that bayes is superior than traditional methods of significance testing, he will be right. But if one believes that bayes removes the problems inherent to significance testing, he will be wrong.

Concerning item correlations, I must recommend the following readings : Raven (2010), Wicherts & Johnson (2009), Rushton & Jensen (2010, p. 16). The first one is the most important to have a grasp on the problem.

Raven, John (2010).

Testing the Spearman-Jensen Hypothesis Using the Items of the RPM.

Wicherts, J. M., & Johnson, W. (2009).

Group differences in the heritability of items and test scores. Proceedings of the Royal Society B: Biological Sciences, 276(1667), 2675-2683.

Rushton, J. P., & Jensen, A. R. (2010).

Race and IQ: A theory-based review of the research in Richard Nisbett’s Intelligence and How to Get It. The Open Psychology Journal, 3(1), 9-35.

The use of MCV with low number of subtests is problematic. And with just 5, MCV has no credibility in my eyes. I have explained that

here and

here.

The CRT seems to be a test first devised by Frederick (

2005) and I first discovered it by reading his intriguing but fascinating article. One thing that strikes me is the shortness of the test. One other problem is that the answers to the test can be accessed by any curious internet users.