Heritability in the personality control system: Ego strength (C), super ego strength (G) and the self sentiment (Q3); by the MAVA Model, Q-Data, and maximum likelihood analyses

Ninety-four identical twins, 124 fraternal twins, 470 brothers (reared together) and 2973 unrelated boys, all in the 12-18 age range were measured on three personality scales - namely ego strength, C, super ego strength, G, and self-sentiment strength, Q3 - adding both forms of the High School Personality Questionnaire (HSPQ). Age corrections brought brothers' scores to equivalence at the same age, and intra-pair and inter family concrete variances were calculated on that basis. The multiple abstract variance analysis (MAVA) method was then used to analyze out of these concrete variances, by solution of simultaneous equations, the underlying abstract contributory variances. The solution of the seven simultaneous equations was made by a maximum likelihood method. Thus within and between family genetic and threptic (environmentally caused) variances were obtained and heritabilities calculated. On a parsimonious MAVA model ignoring genothreptic correlations the population heritabilities were for C, .35, for G, .41 and for Q3, .94. On the full MAVA, undistinguishable in goodness of fit, but hypothesizing two genothreptic parameters, the values fell to .14, .15 and .38, with positive correlation within families and negative or zero between. On averaging with three other extant solutions the values converged on .29, .24 and .62. The bearing of these (and particularly the high between family H for ego strength, namely, .73) on the theories of these traits is discussed. Super ego strength has only minor heritability. Most environmental influence on ego strength occurs within the family constellation. The self-sentiment, Q3 concept must be revised to recognise that it must heavily involve some substantially innate ergic need strengths.