Peter Hans Schönemann (July 15, 1929 – April 7, 2010) was a German-born

psychometrician Psychometrics is a field of study within psychology concerned with the theory and technique of measurement. Psychometrics generally covers specialized fields within psychology and education devoted to testing, measurement, assessment, and rela ...

and

statistical Statistics (from German language, German: ', "description of a State (polity), state, a country") is the discipline that concerns the collection, organization, analysis, interpretation, and presentation of data. In applying statistics to a s ...

expert. He was

professor emeritus ''Emeritus/Emerita'' () is an honorary title granted to someone who retirement, retires from a position of distinction, most commonly an academic faculty position, but is allowed to continue using the previous title, as in "professor emeritus". ...

in the Department of

Psychological Sciences Psychology is the scientific study of mind and behavior. Its subject matter includes the behavior of humans and nonhumans, both conscious and unconscious phenomena, and mental processes such as thoughts, feelings, and motives. Psychology is ...

Purdue University Purdue University is a Public university#United States, public Land-grant university, land-grant research university in West Lafayette, Indiana, United States, and the flagship campus of the Purdue University system. The university was founded ...

. His research interests included

multivariate statistics Multivariate statistics is a subdivision of statistics encompassing the simultaneous observation and analysis of more than one outcome variable, i.e., '' multivariate random variables''. Multivariate statistics concerns understanding the differ ...

multidimensional scaling Multidimensional scaling (MDS) is a means of visualizing the level of similarity of individual cases of a data set. MDS is used to translate distances between each pair of n objects in a set into a configuration of n points mapped into an ...

and measurement,

quantitative Quantitative may refer to: * Quantitative research, scientific investigation of quantitative properties * Quantitative analysis (disambiguation) * Quantitative verse, a metrical system in poetry * Statistics, also known as quantitative analysis ...

behavior genetics Behavioural genetics, also referred to as behaviour genetics, is a field of scientific research that uses genetic methods to investigate the nature and origins of individual differences in behaviour. While the name "behavioural genetics" c ...

test Test(s), testing, or TEST may refer to: * Test (assessment), an educational assessment intended to measure the respondents' knowledge or other abilities Arts and entertainment * ''Test'' (2013 film), an American film * ''Test'' (2014 film) ...

theory A theory is a systematic and rational form of abstract thinking about a phenomenon, or the conclusions derived from such thinking. It involves contemplative and logical reasoning, often supported by processes such as observation, experimentation, ...

and mathematical tools for

social scientists Social science (often rendered in the plural as the social sciences) is one of the branches of science, devoted to the study of societies and the relationships among members within those societies. The term was formerly used to refer to the f ...

. He published around 90 papers dealing mainly with the subjects of

psychometrics Psychometrics is a field of study within psychology concerned with the theory and technique of measurement. Psychometrics generally covers specialized fields within psychology and education devoted to testing, measurement, assessment, and rela ...

and mathematical scaling. Schönemann's influences included

Louis Guttman Louis Guttman (; February 10, 1916 – October 25, 1987) was an American sociologist and Professor of Social and Psychological Assessment at the Hebrew University of Jerusalem, known primarily for his work in social statistics. Biography Louis ( ...

Lee Cronbach Lee Joseph Cronbach (April 22, 1916 – October 1, 2001) was an American educational psychologist who made contributions to psychological testing and measurement. At the University of Illinois, Urbana, Cronbach produced many of his works: the " ...

Oscar Kempthorne Oscar Kempthorne (January 31, 1919 – November 15, 2000) was a British statistician and geneticist known for his research on randomization-analysis and the design of experiments, which had wide influence on research in agriculture, genetics, and ...

and

Henry Kaiser Henry John Kaiser (May 9, 1882 – August 24, 1967) was an American industrialist who became known for his shipbuilding and construction projects, then later for his involvement in fostering modern American health care. Prior to World War II, ...

. Schönemann was a persistent critic of what he considered to be scientifically sanctioned

racism Racism is the belief that groups of humans possess different behavioral traits corresponding to inherited attributes and can be divided based on the superiority of one Race (human categorization), race or ethnicity over another. It may also me ...

psychology Psychology is the scientific study of mind and behavior. Its subject matter includes the behavior of humans and nonhumans, both consciousness, conscious and Unconscious mind, unconscious phenomena, and mental processes such as thoughts, feel ...

. In particular, he claimed that (1)

Arthur Jensen Arthur Robert Jensen (August 24, 1923 – October 22, 2012) was an American psychologist and writer. He was a professor of educational psychology at the University of California, Berkeley. Jensen was known for his work in psychometrics an ...

and others routinely confuse the first

principal component Principal component analysis (PCA) is a linear dimensionality reduction technique with applications in exploratory data analysis, visualization and data preprocessing. The data is linearly transformed onto a new coordinate system such that th ...

(PC1) with '' g'' as

Charles Spearman Charles Edward Spearman, FRS (10 September 1863 – 17 September 1945) was an English psychologist known for work in statistics, as a pioneer of factor analysis, and for Spearman's rank correlation coefficient. He also did seminal work on mod ...

defined it, and that (2) the high IQ heritability estimates reported in the literature derive from restrictive formal models whose underlying assumptions are rarely tested and usually violated by the data.Models and muddles of heritability. Genetica, 99, 97–108
Schönemann died on April 7, 2010.Peter Schönemann Obituary
/ref>

Education

*1953–56 University of Munich (Vordiplom) *1956–59 University of Göttingen (Diplom) *1960–64 University of Illinois (Ph.D. in General Psychology)

Notable work

Schönemann's PhD thesis "A solution of the orthogonal Procrustes problem with applications to orthogonal and oblique rotation," proposed a solution to the

orthogonal Procrustes problem The orthogonal Procrustes problem is a matrix approximation problem in linear algebra. In its classical form, one is given two matrices A and B and asked to find an orthogonal matrix \Omega which most closely maps A to B. Specifically, the orthog ...

. Other Schönemann papers include "A generalized solution of the orthogonal Procrustes problem", "The minimum average correlation between equivalent sets of uncorrelated factors", and "Some new results on

factor Factor (Latin, ) may refer to: Commerce * Factor (agent), a person who acts for, notably a mercantile and colonial agent * Factor (Scotland), a person or firm managing a Scottish estate * Factors of production, such a factor is a resource used ...

indeterminacy" co-authored with M.M. Wang. Schönemann wrote also numerous book chapters, including the "Psychometrics of

Intelligence Intelligence has been defined in many ways: the capacity for abstraction, logic, understanding, self-awareness, learning, emotional knowledge, reasoning, planning, creativity, critical thinking, and problem-solving. It can be described as t ...

" chapter in ''Encyclopedia of Social Measurement'' and the "Heritability" chapter in ''Encyclopedia of Human Intelligence''.

''g'' theory

Spearman's hypothesis asserts a correlation between the g-loadedness of IQ tests and measures of their hereditability, a concept put to work in

's discussion of black—white race differences from the 1980s. Schönemann regarded this work as resting on a conceptual confusion. Schönemann argued for the non-existence of psychometric ''g''. He wrote that there is a fundamental difference between ''g'', first defined by

as a latent one-dimensional variable that accounts for all correlations among any

intelligence tests An intelligence quotient (IQ) is a total score derived from a set of standardized tests or subtests designed to assess human intelligence. Originally, IQ was a score obtained by dividing a person's mental age score, obtained by administering ...

, and a first principal component (PC1) of a positive

correlation matrix In statistics, correlation or dependence is any statistical relationship, whether causal or not, between two random variables or bivariate data. Although in the broadest sense, "correlation" may indicate any type of association, in statistics ...

. Spearman's tetrad difference equation states a necessary condition for such a ''g'' to exist. The important proviso for Spearman's claim that such a ''g'' qualifies as an "objective definition" of "intelligence", is that all correlation matrices of "intelligence tests" must satisfy this necessary condition, not just one or two, because they are all samples of a universe of tests subject to the same ''g''. Schönemann argued that this condition is routinely violated by all correlation matrices of reasonable size, and thus, such a ''g'' does not exist.

Twin studies

In a number of publications, Schönemann argued that the

heritability Heritability is a statistic used in the fields of Animal husbandry, breeding and genetics that estimates the degree of ''variation'' in a phenotypic trait in a population that is due to genetic variation between individuals in that population. T ...

estimates used in most

twin studies Twin studies are studies conducted on Identical twin, identical or Fraternal twin, fraternal twins. They aim to reveal the importance of environmental and genetics, genetic influences for traits, phenotypes, and disorders. Twin research is consid ...

rest on restrictive assumptions which are usually not tested, and if they are, often are found to be violated by the data. He argued that this was true for the

monozygotic Twins are two offspring produced by the same pregnancy.MedicineNet > Definition of Twin Last Editorial Review: 19 June 2000 Twins can be either ''monozygotic'' ('identical'), meaning that they develop from one zygote, which splits and forms two e ...

twins Twins are two offspring produced by the same pregnancy.MedicineNet > Definition of Twin Last Editorial Review: 19 June 2000 Twins can be either ''monozygotic'' ('identical'), meaning that they develop from one zygote, which splits and forms two e ...

raised apart vs. together (MZT) studies (Burt, Shields, Jinks and Fulker, Bouchard) as well as for the more widely used MZT vs

dizygotic Twins are two offspring produced by the same pregnancy.MedicineNet > Definition of Twin Last Editorial Review: 19 June 2000 Twins can be either ''monozygotic'' ('identical'), meaning that they develop from one zygote, which splits and forms two e ...

twins raised together studies. For example, the narrow heritability of responses to the question "did you have your back rubbed" work out to 0.92 heritable for males and 0.21 heritable for females. Using the statistical models published in Loehlin and Nichols (1976) the question "Did you wear sunglasses after dark?" is 130% heritable for males and 103% for females.Totems of the IQ Myth: General Ability (''g'') and its Heritabilities (''h''², HR). 1995 Meetings of the American Association for the Advancement of Sciences

References

External links

Schönemanns' publication list

Power Tables for Analysis of Variance

Alternative measures of fit for the Schönemann-carroll matrix fitting algorithm

Complexity, extremity, and affect in male and female judgments
{{DEFAULTSORT:Schonemann, Peter Hans German statisticians Purdue University faculty Ludwig Maximilian University of Munich alumni University of Göttingen alumni University of Illinois alumni People involved in race and intelligence controversies 1929 births 2010 deaths Emigrants from West Germany to the United States Psychometricians