I'm intrigued by the structure of some correlations after a hierarchical, or second order, factor analysis
The explanation in the paper only goes as far as to say
3.3. Intercorrelations between psychopathic, narcissistic, Machiavellian, and sadistic traits
Psychopathic, narcissistic, Machiavellian and sadistic traits were moderately correlated, with Pearson’s r ranging from .27 to .37 (Fig. 1). To evaluate if the different measures of these four traits loaded on a more general second-order factor, we conducted a hierarchical analysis of oblique factors which showed there was not a general deviant personality factor that was likely to reflect all types of traits. There appeared to be four primary unique factors corresponding to psychopathic, narcissistic, Machiavellian and sadistic traits. The four constructs thus obtained, appeared to display a greater degree of independence than the original four, with Pearson’s r ranging from .01 to .26 (Fig. 1).
So how should one interpret the fact that after the rotation there was almost no correlation between psychopathy and machiavellianism while there still was quite a bit between psychopathy and sadism? The difference is higher than before the rotation. Does that indicate that the unrotated correlation between psychopathy and machiavellianism is solely an artifact of the diagnostic instruments (questionnaires) used?