Peter Schonemann on IQ

Peter H. Schonemann

Selected Publications:
For the complete bibliography and abstracts:

(1978) Schonemann and Steiger, J. H.  On the validity of indeterminate factor scores. Bulletin of the Psychonomic Society, 12, 287-290. 

(1981).  Factorial definitions of intelligence:  Dubious legacy of dogma in data analysis.  In I. Borg (Ed.), Multidimensional data representations: When and why.  Ann Arbor:  Mathesis Press, 325-374. 

(1983).  Do IQ tests really measure intelligence?  Commentary, The Behavioral and Brain Sciences, 6, 311-315.

(1987).  Jensen's g: Outmoded theories and unconquered frontiers. In S. and C. Modgil (Eds.), Arthur Jensen: Consensus and Controversy.  Barcombe: Falmer Press, 313-327. 
Abstract:  An invited chapter to a volume devoted to Arthur Jensen's work. Originally, the editors intended to have two contributors per topic, one favorable and the other critical. As it turned out, only two of the contributors were critical, the other one being James R. Flynn ("Flynn effect"). The title borrows from Jensen, A.R. (1979) "g: Outmoded theory or unconquered frontier?' Creative Science and Technology, 11, 16-29. The main story is contained in sec. 4, The great Society. It gives a concrete and elementary illustration of the factor indeterminacy issue, complete with two sets of equivalent factor scores for the same 8x3 score matrix. For a more abstract treatment, see Schonemann and Steiger (1978).

(1989).  New questions about old heritability estimates. Bulletin of the Psychonomic Society, 27(2), 175-178. 
This note summarizes the main results of three recent studies on the heritability of mental traits:
(1) The inferences Jinks and Fulker (1970) derived from Shields' (1962) twin data are invalid since the assumptions of the
genetic model are consistently violated by these data. A purely environmental model fits them better by a factor of 2.
(2) Holzinger's heritability coefficient (h**2) is invalid since his derivations imply that dizygotic twins share no genes.
(3) In contrast, Nichols' (1965) heritability coefficient (HR) follows from a strictly additive genetic model.
(4) However, the needed assumptions are consistently violated by Osborne's (1980) personality data, which produce an
excessive number of inadmisible HRs. A purely environmental model fits these data better by a factor of 14.
Jointly, these results suggest that heritability estimates of mental traits in the literature should be view with caution.

(1989).  Some new results on the Spearman hypothesis artifact.  Bulletin of the Psychonomic Society, 27(5), 462-464.
This note constitutes a summary of the main results of two papers devoted to Jensen's (1980) "Spearman Hypothesis":
(1) Elementary geometry shows that positive ("Spearman") correlations between the mean black/white difference vector and
the leading eigenvector of correlation matrices are artifacts, regardless how one interprets Jensens's ambiguous definitions of
"Spearman's hypothesis" (Level I versus Level II interpretation).
(2) Empirically, the stronger Level II interpretation (which predicts positive correlations with both within eigenvectors) also
arises with data that have nothing to do with g, such as SES variables indicating the number of toys and games.
(3) Mathematically, the Level II interpretation implies not just approximate but perfect collinearity between the mean difference
and the eigenvectors of all three covariance matirces, if one assumes multinormality, positivity of both subgroup covariance
matrices, and an equal split into a HI and a LO group, regardless whether Spearman's factor model holds or not.

(1990).  A critique of the Jinks and Fulker reanalysis of Shields' identical twin data. Abstract.  20th Annual Meeting Program and Abstracts of Behavior Genetics Association.  Aussois, France, p. 54.

(1990).  Environmental versus genetic variance component models for identical twins: A critique of Jinks and Fulker's reanalysis of the Shields data.  Cahiers de Psychologie Cognitive /  European Bulletin of Cognitive Psychology, 10, 451-473. 
It is shown that the genetic model Jinks and Fulkr (1970) fitted to the Shields' (1962) twin data is qualitatively inconsistent with
systematic trends in these data and, as a result, produces an inordinately large proportion of negative variance estimates. In contrast, a purely environmental model yields qualitative predictions consistent with the Shields data and admissible parameter estimates throughout. Quantitatively, it fits the Shields data twice as well as Jinks and Fulker's genetic model. Hence their farreaching conclusions are not supported by the Shields data.  This reevaluation illustrates that purely descriptive models, even if they were used with circumspection, remain intrinsically inconclusive about nature/nurture questions because the possibility can never be ruled out that other models may fit the same data even better. 

(1990).  Not beyond a reasonable doubt.  Cahiers de Psychologie Cognitive - European Bulletin of Cognitive Psychology, 10, 671-674.

(1992).  Extension of Guttman's result from g to PCI.  Multivariate Behavioral Research, 27, 219-224. 

(1992).  Henry F. Kaiser 1927-1992.  Multivariate Behavioral Research, 27(1), 161-163.

(1993).  A note on Holzinger's heritability coefficient h**2.  Chinese Journal of Psychology, 35, 61-67. 
It is shown that the still widely used heritability estimate h**2 developed by Holzinger (1937) is not valid because Holzinger's
derivation of it was unsound: The variance component model he used to derive h**2, together with his claim that it estimates
the genetic variance ratio, imply the counterfactual assertion that dizygotic twins share no genes. While the competing coefficient, Nichols' HR does indeed follow from the conventional variance component model, the necessary conditions it rests on lack empirical face validity.

Sch�nemann & Sch�nemann, R. D. (1994).  Environmental versus genetic models for Osborne's personality data on identical and fraternal twins.  Cahiers de Psychologie Cognitive - Current Psychology of Cognition 13, 141-167. 
It is shown that the additive genetic model of Nichols needed to justify the heritability ratio HR does not fit Osborne's (1980)
data very well. A purely environmental model with the same number of parameters fits these data better by a factor of 14.
Compared with the additive genetic model, these empirical results suggest that Osborne's personality data contain no genetic
component at all. The responses of the identical twins may be more similar simply because they are exposed to more similar
environments than fraternal twins. This outcome illustrates the general principle that conventional variance component models used to justify heritability estimates are intrinsically inconclusive: We can never rule out that another, qualitatively quite different model may fit the same data equally well or, as in the present case, much better.

(1994).  Heritability.  In R Sternberg (Ed.), Encyclopedia of Human Intelligence.  New York:  McMillan, p. 528-536.

( 1995) Totems of the IQ Myth:  General Ability (g) and its Heritabilities (h**2, HR).  1995 Meetings of the American Association of Sciences

Sch�nemann & Thompson, W.W. (1996) Hit-rate bias in mental testing. Cahiers de Psychologie  Cognitive-Current Psychology of Cognition, 3-28.
New results are given concerning a form of test bias which, in the past with few exceptions (esp. Cole, 1973; Hartigan &
Wigdor, 1989) seems to have been largely ignored. We call it "hit-rate bias" because it is defined as the discrepancy between
the hit-rates (= probability that a qualified testee passes the test) in a low and a high scoring group. Typically, it favors the
high-scoring group. In contrast to Cole (1973), our focus in on binary criteria, such as college graduation. In the first, theoretical part, we present a (Hit-Rate Bounds) Theorem which underscores that raising predictor standards is not
equivalent to raising criterion standards, as some believe. Instead, it typically increases hit-rate bias. We then derive and tabulate a simple approximation for estimating hit-rates as a function of validity, base-rate, and admission quota. In the empirical portion of the paper, we evaluate the extent of hit-rate-bias in practice by re-analyzing a number of data sets
involving the SAT, the ACT, and the GATB. Finally, we discuss how the addition of tst score to high school record affects
hit-rate bias in predicting college graduation. We find it increases the bias.

(1997).  Models and muddles of heritability.  Genetica, 99, 97-108. 
One reason for the astonishing persistence of the IQ myth in the face of overwhelming prior and posterior odds against it may
be the unbroken chain of excessive heritability claims for 'intelligence', which IQ tests are supposed to 'measure'. However, if,
as some critics insist, 'intelligence is undefined, and Spearman's g is beset with numerous problems, not the least of which is
universal rejection of Spearman's model by the data, then how can the heritability of 'intelligence' exceed that of milk production
of cows and egg production of hens? The thesis of the present review paper is that the answer to this riddle has two parts: (a) the technical basis of heritability claims for human behavior is just as shaky as that of Spearman's g. For example, a once widely used 'heritability estimate' turns out to be mathematically invalid, while another such estimate, though mathematically valid, never fits any data; and (b) valid technical criticisms of flawed heritability claims typically are met with stubborn editorial resistence in the main strream journals, which tends to calcify such misinformation.

(1997)  Some new results on hit rates and base rates in mental testing. Chinese Journal of Psychology, 39, 173-192.

(1998) Famous artefacts: Spearman's Hypothesis. Cahiers de Psychologie Cognitive / Current Psychology of      Cognition, 16, 665-698 (Target Article). 
In a number of publications, Jensen has recalled Spearman's (1927, p.379) observation that the loadings of the first principal
component (PC1) of various 'intelligence tests' tend to correlate positively with the corresponding Black/White mean
differences ('Spearman's Hypothesis'). Jensen believes this sheds light on the true nature of g, Level II Ability, test bias, and Black/White differences. His claims have been warmly welcomed in some quarters (most recently by Herrnstein and Murray, 1994) as conclusive confirmation of the Black inferiority myth.
Here it is shown by way of empirical, numerical, geometric, and algebraic demonstrations tht the positive correlations predicted
by Spearman's hypothesis are psychometric artefacts which also arrise
(a) with measures which have nothing to do with 'general ability', for example, the number of toys and books a
child has, and, more generally
(b) with any set of moderately correlated random data, once the sample is split into high and low groups.
Specifically, this interpretation predicts that, if sample sizes differe substantially, then the correlation will be larger for the PC1 of
the larger group. This prediction is borne out both in simulated and in 'real' data sets, including Jensen's.

(1998) The rise and fall of Spearman's Hypothesis. Cahiers de Psychologie Cognitive, 16, 788-812 (Response).

(1999) The amazing grace of common sense. Cahiers de Psychologie Cognitive/ Current Psychology of Cognition, 18, 232-240.

(2001) Better never than late: Peer review and the preservation of prejudice. Ethical Human Sciences and Services, 3, 7-21.

(2002) Some new results on Spearman's Hypothesis. Chinese Journal of Psychology, 44, 137-150.

(2003) Schonemann and Jaccard, J. Expected mean squares for extended twin designs. A projection approach. Abstract. Chinese Journal of Psychology, 45, 4, 337-343.

(2005) Psychometrics of Intelligence. K. Kemp-Leonard (ed.) Encyclopedia of Social Measurement, 3, 193-201. Abstract.

(2008) Erratum. Some algebraic relations between involutions, convolutions and correlations, with applications to holographic memories. Biological Cybernetics, 98, 355.

(2008) Schonemann and Scargle, J. D. A generalized publication bias model. Chinese Journal of Psychology, 50, 21-29. Abstract. Editorial Comments and Reviews.

(2008) Jerry Hirsch 1922-2008. Scientist, Rebel. Institute for the Study of Scientific Racism.

(2009) Schonemann and Heene, M. Predictive validities: figures of merit or veils of deception? Psychology Science Quarterly, 51, 195-215. Abstract.