Paul T Barrett

• BSc, PhD
• Chief Research Scientist at Cognadev Ltd

This article outlines the history and development of the Junior Eysenck Personality Questionnaire (JEPQ) by Professor Hans J. Eysenck and Dr. Sybil B.G. Eysenck, which culminated in sampling tens of thousands of children and adolescents across many countries, aided by psychologists in each country. The cross-cultural analysis methodology is then br...

The European Federation of Psychologists’ Associations (EFPA) has issued sets of test standards and guidelines for psychometric test reviews without any attempt to address the critical content of many substantive publications by measurement experts such as Joel Michell. For example, he has argued that the psychometric test-theory which underpins cl...

Four data sets from studies included in the Reproducibility Project were re-analyzed to demonstrate a number of flawed research practices (i.e., “bad habits”) of modern psychology. Three of the four studies were successfully replicated, but re-analysis showed that in one study most of the participants responded in a manner inconsistent with the res...

Background: There is limited evidence on caregiver outcomes associated with mild cognitive impairment in patients with Parkinson's disease (PD-MCI) and the coping strategies used by these caregivers. Methods: To investigate this relationship, we examined levels of burden, depression, anxiety, coping strategies and positive aspects of caregiving...

This article is about why and how Hans Eysenck began investigating the brain evoked potential and sensory nerve conduction correlates of psychometric IQ, his investigations into the timed/speeded performance (chronometrics) results being published by Art Jensen, and the initial results being reported by Doug Vickers and Ted Nettelbeck on the relati...

-Social scientists are often interested in computing the proportion of overlap and nonoverlap between two normal distributions that are separated by some magnitude. In his popular book, Statistical Power Analysis for the Behavioral Sciences (1988, 2nd ed.), Jacob Cohen provided a table (Table 2.2.1) for determining such proportions from common valu...

This article has no abstract.

Cross-cultural projects were undertaken, over some 25 years, to standardise the EPQ (both Adult and Junior forms) for many countries (See Appendix B for a list).Together with the rationale as to why these studies were undertaken, the statistical methodology is explained. Although the studies were published, it seemed timely to list them, together w...

The structure of the Eysenck Personality Inventory (EPI) is poorly understood, and applications have mostly been confined to the broad Neuroticism, Extraversion and Lie scales. Using a hierarchical factoring procedure, we mapped the sequential differentiation of EPI scales from broad, molar factors to more specific, molecular factors, in a UK popul...

Serious criticisms of psychology’s research practices and data analysis methods date back to at least the mid-1900s after the Galtonian school of thought had thoroughly triumphed over the Wundtian school. In the wake of Bem’s (2011) recent, highly publicized study on psi phenomena in a prestigious journal, psychologists are again raising serious qu...

Three samples of volunteer working adult participants, drawn from two countries (United Kingdom and New Zealand), provided data using the pencil and paper version of the Occupational Stress Indicator questionnaire (OSI; Cooper, Sloan, & Williams, 1988). In an attempt to examine the degree to which the psychometric structure of the test was reflecte...

The meta‐analytic correlation between two Big Five factors Something is not quite right in the woodshed

There has been considerable interest in the directionality of resource specialisation during the diversification of lineages. We developed a quantitative method to investigate habitat specialisation in a radiation of New Zealand triplefin fishes, as habitat use appears to be an important axis of diversification in this marine group. The degree of s...

Real job applicants completed a 5-factor model personality measure as part of the job application process. They were rejected; 6 months later they (n = 5,266) reapplied for the same job and completed the same personality measure. Results indicated that 5.2% or fewer improved their scores on any scale on the 2nd occasion; moreover, scale scores were...

For journal editors, reviewers, and readers of research articles, structural equation model (SEM) fit has recently become a confusing and contentious area of evaluative methodology. Proponents of two kinds of approaches to model fit can be identified: those who adhere strictly to the result from a null hypothesis significance test, and those who ig...

Recent work has shown that habitat specialisation can lead to diversification in lacustrine and marine fish species. Here we investigate specialisation in the New Zealand triplefin fish fauna (Tripterygiidae), which has the greatest diversity and disparity of triplefin species in the world with 26 endemic species. Most species are sympatric through...

The Clinical Outcomes in Routine Evaluation-Outcome Measure (CORE-OM) is a self-report measure comprising 28 items tapping three domains; subjective well-being, psychological problems and functioning. In addition to the potential theoretical value of the domains for operationalizing the phase model of psychotherapy, when consulted, managers and cli...

McGrath (2005/this issue) has published a very significant article; it is significant because it examines the substantive issue of construct validity in a simple and informative way, noting the confusions apparent in how constructs and their variables are defined, used, and interpreted within the domain of personality and individual differences. Th...

This article has no abstract.

Many people download my old 1980 paper: Barrett, P.T. & Kline, P. (1980) The observation to variable ratio in factor analyses. Personality and Group Behaviour, 1, 1-33 .. But I'd also revisited this issue back in 2005 - with a Technical whitepaper which looked at the issue from a different perspective, incorporating what was more recent evidence/c...

A statement from Michell (Michell, J., “Normal science, pathological science, and psychometrics”, Theory and Psychology, Vol. 10 No. 5, 2000, pp. 639-67), “psychometrics is a pathology of science”, is contrasted with conventional definitions provided by leading texts. The key to understanding why Michell has made such a statement is bound up in the...

Kuwaiti (n=204) and American (n=137) undergraduates responded to the Arabic Obsessive-Compulsive Scale in Arabic and English languages, respectively. Based on the scree test, a principal components (principal axis) factor analysis with an Oblimin rotation yielded three factors in both samples. The factors were labeled (1) obsessive thoughts, (2) or...

To examine the incidence and characteristics of re-admissions to the State Hospital over the six year inclusive period of January 1992 to December 1997. RESONS FOR THE STUDY: RISK ASSESSMENT: A re-admission to a high-security setting may be the result of a failed risk assessment at the time of discharge. An analysis of re-admissions might reveal fa...

In this paper, the entire range of current and leading-edge methodologies for the assessment of integrity, honesty, and deception are outlined and briefly reviewed. The relevant evidence for and accuracy of each methodology is also presented. Particular regard is paid to questionnaire measures of integrity and honesty, as this is the current growth...

The authors were also given access to the ASE UK volunteer standardisation sample (N=1575) 16PF-5 scale correlation matrix. Using SEPATH (Statistica, 1999), the loadings above |0.3| in table 1.4 of the US manual for the 16PF-5 were specified as paths to be estimated. All other loadings were defaulted to 0.0. The factor correlations from the US Tech...

There is a curious reticence amongst test publishers concerning the possible distortion of item responses within samples of individuals who stand to gain or lose some reward, depending upon their responses to a questionnaire. If the distortion is hypothesised as resulting in changed scores on a set of questionnaire scales, then it is understandable...

The factorial similarity of Psychoticism (P), Extraversion (E), Neuroticism (N), and Social Desirability (L), as measured by the Eysenck Personality Questionnaire, was assessed using gender- specific data collected from 34 countries. As in an earlier study using data from 24 countries (Eysenck et al., 1985), the Kaiser-Hunka-Bianchini (KHB) procedu...

Bates and Eysenck (1993), used a 3rd-order cubic polynomial curve fitting procedure on correct-response probabilities computed from the trial record of individual research participants (N = 70) in an inspection time (IT) task. They demonstrated that this methodology produced estimates of IT that, when correlated with full-scale IQ scores (assessed...

In a response to the Ng, Cooper, and Chandler (1998) paper on the structure of the JEPQ in Hong Kong children, three issues were discussed that cast doubt upon the conclusions reached by Ng et al. These issues concern firstly, the subjective adoption of factor names established in one questionnaire to describe factors of items drawn from a differen...

Using three samples of applicant data, encompassing over 2300 participants, the Concept Model 5.2 Occupational Personality Questionnaire (OPQ) was examined for scale discriminability at the item, scale and factorial level. Item analysis and maximum likelihood factor analysis indicated that the OPQ questionnaire provided good, low complexity measure...

The Occupational Personality Questionnaire (Concept 5.2, OPQ; Saville et al., 1993) contains 248 items measuring 31 scales. Each scale has eight items. Responses to each item are on a normative five-point rating scale. Reliability coefficients (alpha) range from .57 to .88, with a median alpha of .75. Since alpha is known to depend on scale length...

The Gray-Wilson Personality Questionnaire (GWPQ) was administered in translation to 597 Japanese college students. The sex differences previously found with a British sample were replicated as well as two others; males were higher on Fight and Approach, while females were more disposed towards Flight and Active Avoidance. Intercorrelations among GW...

-This study reports on the gender differences in the responses ro 34 questions comprising the Eysenck Personality Questionnaire, as recorded by 508 males and 873 females who constituted the American standardization group for he questionnaire. The mean difference on the resulting M-F scale is statistically significant, being 2.28f 0.30 for the Briti...

There has been a recent increase in the use of PCs to measure Inspection Time. The problems associated with such an approach are outlined and a lower bound display time is identified for future workers in this area.

Four hundred and eighty three Iranian boys and 593 Iranian girls completed the Junior Eysenck Personality Questionnaire. Reliabilities (alpha coefficients) were all high except that for extraversion in girls. Intercorrelations of the scales showed a high social desirability involvement with Psychoticism (P) and Neuroticism (N), suggesting dissimula...

Two hundred subjects provided data from within three separate studies that attempted to replicate correlations between averaged evoked potential (AEP) indices and psychometric IQ. In addition, AEP zero-cross analysis was undertaken as a specific test of a proposition made within the Weiss quantum theory of intelligence. Measures of AEP variability,...

We have tested the hypothesis in this study that different methods of administering a questionnaire produce differential approximations to truthful admission of undesirable personality traits and behaviours. Four different methods of administration produced different levels of trust and understanding, using the current prediction among healthy subj...

We have tested the hypothesis in this study that different methods of administering a questionnaire produce differential approximations to truthful admission of undesirable personality traits and behaviours. Four different methods of administration produced different levels of trust and understanding, using the current prediction among healthy subj...

We have tested the hypothesis in this study that different methods of administering a questionnaire produce differential approximations to truthful admission of undesirable personality traits and behaviours. Four different methods of administration produced different levels of trust and understanding, using the current prediction among healthy subj...

The matrix of intercorrelations between scales of schizotypy presented by Kendler and Hewitt in 1992 was reanalyzed, and results rather different from those reported by the original authors were found. The new structure shows good agreement with the theory of personality disorder published by Eysenck in 1987. In all, the different scales seem to fa...

A replication was undertaken of our previous work relating the conduction parameters of variability and velocity of the electrically stimulated peripheral median nerve to psychometric test IQ and EPQR Psychoticism. Once again, we failed to find any significant correlation between measures of nerve conduction velocity and IQ. Further, we failed to r...

Six hundred and fifteen male and 642 female Canadian subjects completed the Eysenck Personality Questionnaire-Revised in Canada. All but one factor comparison exceeded 0.90 and this and an independent space analysis confirmed that the factors of P, E, N and L were identical in Canada as in England. Reliabilities were very high except for P, which w...

An attempt to replicate the Hendrickson (Hendrickson & Hendrickson, 1980, 1982) paradigm and results was undertaken on 40 subjects. The Hendrickson “rules for replication were also empirically examined with regard to their basis in fact rather than presumption. In addition to computing the specific Hendrickson measures of string, variability, and c...

Eighty-seven women who enjoyed using sadomasochistic components in their sexual life completed the Eysenck Personality Questionnaire, a slightly modified version of the Wilson Sexual Fantasy Questionnaire and demographic questionnaires exploring the sadomasochistic and other features of their sexual lifestyle, the results being compared with those...

538 males and 529 females completed the translated Eysenck Personality Questionnaire (EPQ) in Russia. Factor comparisons all exceeded 0.95 except that for Psychoticism (P) for females which was 0.92. We may, therefore, assume that the factors of Extraversion (E), Neuroticism (N) and Social Desirability or Lie scale (L) are measuring the same in Rus...

Principal components analysis of the Gray-Wilson Personality Questionnaire revealed six fairly independent factors that bore only a partial resemblance to the six animal behaviour paradigms that the test was devised to measure. Taken together with the inter-scale correlations reported previously this raises certain questions about the application o...

One-hundred and nine adult subjects were tested on two occasions using a set of computer administered letter series problems. Using methods introduced by Furneaux [In Eysenck, H. J. (Ed.), Handbook of abnormal psychology. New York: Basic Books, 1961], response times were analysed in order to provide estimates of item difficulties based on time to c...

Examined the relationships between averaged sensory nerve action potentials (ASNAPs), scores on the Advanced Progressive Matrices (APM) and the Eysenck Personality Questionnaire (EPQ), and parameters computed from a choice reaction time (RT) task in 44 Ss (aged 18–41 yrs). ASNAP variability was correlated negatively with ability as measured by the...

The development of the Gray-Wilson Personality Questionnaire is described; this is an instrument designed to measure human equivalents of six animal behaviour paradigms--Approach, Active Avoidance, Passive Avoidance, Extinction, Fight and Flight. Although these six scales showed satisfactory internal consistency they failed to link up into the thre...

A group of 113 smokers of normally distributed IQ was tested on two occasions on a choice reaction time task and the newly introduced ‘odd-man-out’ task. Performance on these two tasks was found to correlate significantly with IQ and personality variables as measured by the WAIS-R intelligence test and the EPQ and IVE. The effect of smoking on thes...

Do girls fall in love with an image of their father? This study tested the hypothesis that, in choosing a partner, people tend to replicate the physical and mental attributes of their opposite-sex parent more than of the same-sex parent. A sample of 314 women, mostly in their late teens and describing themselves as ‘in love’, supplied details of th...

Two large-scale applications of the EPQ were carried out on U.S. samples and the dimensions of personality resulting from factor analyses of the resulting matrices of intercorrelations compared with similar data obtained from the original standardization groups of the EPQ in England. It is concluded that very similar factor structures obtained in t...

Three coefficients of factor similarity were examined with regard to their behaviour within four sets of data. Two simple methods using Pearson r correlations and Tucker Congruence coefficients were compared with a more complex method given by Kaiser, Hunka and Bianchini (1971). Three of the data sets involved the use of 100 random data matrices, t...

Two samples of adult subjects of reasonably average intelligence were given IQ tests and a series of RT tests using 0, 1, 2, and 3 bits of information in a Hick paradigm. Both series showed negative correlation between IQ on the one hand, and RT and σRT, on the other, confirming earlier work. On the other hand, there was no evidence of correlation...

In view of certain psychometric deficiencies of the original Psychoticism scale, an attempt was made to improve the scale by adding new items. It was attempted to increase the internal reliability of the scale, improve the shape of the distribution and increase the mean and variance score. Two different studies are discussed. Reliabilities are now...

The Wilson-Patterson Conservatism Scale was given to 34 schizophrenic and 34 non-schizophrenic patients in a Dutch mental hospital. The absence of liberal-scoring schizophrenics was interpreted as consistent with the theory that the social withdrawal seen in chronic schizophrenia represents a strategy for coping with stimulus overload. Internal con...

Any discussion of the measurement of intelligence is likely to be handicapped by the many different meanings the term has assumed in psychology, to say nothing of popular discourse. It is useful to distinguish the three major meanings of the term, which are shown in Figure 1. Intelligence A is the genotypic, biological underlay of all cognitive act...

The means for each scale score from the Eysenck Personality Questionnaire were compared individually and conjointly across 25 countries. Comparisons were carried out using coded difference scores, Pearson correlations, Euclidean distances, cluster analyses and non-metric multidimensional scaling. It was possible to compare the personality (as defin...

The present authors attempt to demonstrate, based on their own research and from a critical analysis of other research in the field, that the variables measured by the plethora of personality tests, despite their disparate labels, are not in fact distinct and that in reality a small and well validated set of factors can be extracted from these test...

The validity of the alternate forms of the Multidimensional Health Locus of Control scale and the underlying dimensionality of the three test scales were investigated using 70 male and 77 female British university students. A classical item analysis, principal component and image component factor analysis were undertaken. The results indicated that...

Helmes (1980) presented results demonstrating that the purported factors of the Eysenck Personality Questionnaire (EPQ) did not emerge in a sample of 191 undergraduates. However, this conclusion was reached using incorrect factor analytic methodology. Helmes not only used an idiosyncratic version of Eysenck's original methodology but also failed to...

An extensive series of analyses were carried out on a sample of data from 491 undergraduate university students who completed Form A of Cattell's 16PF questionnaire. The data was item analysed, factored using both principal component and image analyses, and radial parcelled. However, even though five different factor solutions were rotated to a max...

The Eysenck Personality Questionnaire (EPQ) was back translated into Thai and administered to a sample of 116 male and female Thai University students. The EPQ items were then submitted to item analyses and a rotated factor analysis and the results were compared with those from a large British sample. Neuroticism (N), Extraversion, and Social Desir...

Many investigators have suggested a minimum ratio of observations to variables or an absolute minimum of observations to obtain stable factor patterns. The present authors examined this problem by contrasting instability that was due to very low ratios with that due to very low quantities of observations. Data from 491 college students' responses t...

Hierarchical factor analyses were carried out on raw scored EPQ data yielded from two samples of subjects, a Gallup adult quota sample of 1198 subjects and 406 university undergraduates. Each sample was split by sex providing six data sets for analysis. Results at the second order level clearly indicated the recovery of practically all the E, N and...

Two questionnaires designed by Howarth (HPQ, APF2) whose factor space in unexplored and the EPQ (Eysenck) were jointly scale factored on 79 subjects, under the hypothesis that Eysenck's superfactors of P, E, and N should be represented as major influences in the resultant factor structure. A prinicipal component analysis yielded 7 factors from 24 b...

This paper attempts to put forward the proposition that practically all of the measurement made within occupational psychology is of ambiguous scientific status. However, the definition of what constitutes scientific investigation and quantitative scientific measurement, required in order to permit the forwarding of this proposition, is very specif...

This paper outlines the background, rationale, and strategy that encompasses the 22 years of Eysenck investigations into the cross-cultural comparison of the four personality "superfactors" measured by the Eysenck Personality Questionnaire. This effort has not taken place without encountering criticism of both its methodology and psychological mean...

Using three samples of applicant data, encompassing over 2300 partiCipants, the Concept Model 5.2 Occupational Personality Questionnaire (OPQ) was examined for scale discriminability at the item, scale and factorial level. Item analysis and maximum likelihood factor analysis indicated that the OPQ questionnaire provided good, low complexity measure...