Residual group-level factor associations: Possibly negative implications for the mutualism theory of general intelligence

Article history: Received 2 July 2015 Received in revised form 15 January 2016 Accepted 18 January 2016 Available online 30 January 2016 Themutualism theory of general intelligence (g) posits that the positivemanifold arises because ofmutually beneficial interactions between originally orthogonal cognitive abilities, rather than because of a genuine general construct. In a recent investigation, Gignac (2014) reported that the strength of g was largely constant from the ages of 2.5 to 90 years, which was interpreted as an indirect failure to confirm the mutualism theory of g. In this investigation, a second indirect test of the mutualism theory of g was performed. Specifically, it was hypothesized that, if the extendedmutualism theory of g is plausible, then there should be some consistent, positive associations between group-level factors, controlling for the effects of a general factor. To examine this possibility, the associations between cognitive ability group-level factors were estimated across a series of seven relatively large and relatively representative samples of intelligence battery data. Next, seven single-factor models were estimated against the seven group-level inter-correlation matrices. The corresponding single-factor residual correlation matrices were observed to yield an approximately equal number of positive and negative residual correlations and an overall mean of zero. Furthermore, the only moderately consistent residual effect was a negative association between crystallised intelligence and processing speed. Although only an indirect test, the results are interpreted to be more supportive of g factor theory than mutualism. © 2016 Elsevier Inc. All rights reserved.