Scientific Work
Formann led long-standing research collaborations with colleagues in the statistical, medical, and psychological sciences. His substantial research activities in all these fields are documented in numerous books and more than 50 publications in prestigious
high-impact journals, including
Biometrics, the
Journal of the American Statistical Association, the
British Journal of Mathematical and Statistical Psychology, and
Psychometrika.
Item response theory (Rasch models) Formann was one of the first researchers who documented problems with
Rasch model tests, in particular with
Andersen's likelihood-ratio test which arise under certain conditions if it is employed conventionally. As a senior author, Formann also showed that the common assumption that the
EM estimation of the two-parameter logistic model is not influenced by initial values is incorrect. (based on
Raven's matrices test) which has since been widely used in research and practice. A revised version of this language-free
intelligence test that has been calibrated against large contemporary samples of men and women is forthcoming.
Latent Class Analysis For his first
habilitation (in psychology), Formann published a comprehensive
monograph on
latent class analysis which continues to be widely cited for its clarity, depth, and originality, and hence is considered a true modern classic on this topic.
Quantitative Methods for Research Synthesis (Meta-Analysis) In his later research, Formann addressed, among other things, the problem of
publication bias in
meta-analytic research. He introduced a novel method that allows estimating the proportion of studies missing in meta-analysis due to
publication bias based on the
truncated normal distribution. In 2010, as the senior author, Formann debunked in a meta-analysis the famous
Mozart effect as a myth.
Other Newcomb-Benford Law Formann provided an alternative explanation for the
Newcomb-Benford law – a formalisation of the remarkable observation that the
frequencies with which the leading
digits of numbers occur in large
data sets are far away from being
uniform (e.g., the leading digit 1 occurs in nearly one third of all cases). In addition to the prevailing explanations based on
scale- and base invariance, Formann directed the attention to the interrelation between the
distribution of the significant digits and the distribution of the
observed variable. He showed in a simulation study that long right-tailed distributions of a
random variable are compatible with the Newcomb-Benford law, and that for distributions of the ratio of two random variables the fit generally improves.
Piaget's Water Level Task The
water-level task refers to a task developed by
Jean Piaget where bottles filled with different levels of water are presented in different
angles of orientation. It is used to assess the level of
mental development of spatial abilities (e.g., recognition of the invariance of horizontality). Formann criticized the established method of
dichotomizing water-level responses by the subjects into "right" versus "wrong" – he showed that this method was inappropriate because it ignored the heterogeneity of the task difficulties - and instead recommended using
latent class models or
Rasch models. He showed that subjects and tasks can be arrayed on a
unidimensional scale and, by employing the linear logistic test model, that the task difficulty could be attributed to a single
parameter associated with the angle of
inclination of the bottle.
Misconception of Probability Formann compared the performance in the classic
birthday problem (i.e., guessing the probability
P for any coincidence among
N individuals sharing the same birthday) and the birthmate problem (i.e., guessing the probability
P for the specific coincidence among
N individuals of having a birthday today) in psychology
undergraduates, casino visitors, and casino employees. Psychology students and women did better on both task types, but were less confident about their estimates than casino visitors or personnel and men. Higher confidence ratings were related to subjective estimates that were closer to the solutions of birthday problems, but not of birthmate problems.
Parallel Analysis in Retrieving Unidimensionality in the Presence of Binary Data Formann provided both theoretical and empirical evidence that the application of the
parallel analysis for uncovering the
factorial structure of
binary variables is not appropriate. Results of a simulation study showed that
sample size,
item discrimination, and type of
correlation coefficient considerably influence the performance of parallel analysis. ==Selected publications==
Selected publications
Papers • Formann, A. K. (1978). Note on parameter-estimation for Lazarsfeld latent class analysis. Psychometrika, 43, 123-126. • Formann, A. K. (1985). Constrained latent class models: Theory and applications. British Journal of Mathematical and Statistical Psychology, 38, 87-111. • Formann, A. K. (1986). A note on the computation of the 2nd-order derivatives of the elementary symmetrical functions in the Rasch model. Psychometrika, 51, 335-339. • Formann, A. K., & Rop, I. (1987). On the inhomogeneity of a test compounded of 2 Rasch homogeneous subscales. Psychometrika, 52, 263-267. • Formann, A. K. (1988). Latent class models for nonmonotone dichotomous items. Psychometrika, 53, 45-62. • Formann, A. K. (1989). Constrained latent class models: Some further applications. British Journal of Mathematical and Statistical Psychology, 42, 37-54. • Formann, A. K. (1992). Linear logistic latent class analysis for polytomous data. Journal of the American Statistical Association, 87, 476-486. • Formann, A. K. (1993). Fixed-distance latent class models for the analysis of sets of two-way contingency tables. Biometrics, 49, 511-521. • Formann, A. K. (1994). Measurement errors in caries diagnosis: Some further latent class models. Biometrics, 50, 865-871. • Formann, A. K. (1994). Measuring change in latent subgroups using dichotomous data: Unconditional, conditional, and semiparametric maximum-likelihood-estimation. Journal of the American Statistical Association, 89, 1027-1034. • Formann, A. K., & Kohlmann, T. (1996). Latent class analysis in medical research. Statistical Methods in Medical Research, 5, 179-211. • Formann, A. K., & Kohlmann, T. (1998). Structural latent class models. Sociological Methods and Research, 26, 530-565. • Formann, A. K. (2001). Misspecifying latent class models by mixture binomials. British Journal of Mathematical and Statistical Psychology, 54, 279-291. • Formann, A. K., & Ponocny, I. (2002). Latent change classes in dichotomous data. Psychometrika, 67, 437-457. • Formann, A. K. (2003). Latent class model diagnosis from a frequentist point of view. Biometrics, 59, 189-196. • Formann, A. K. (2003). Modeling data from water-level tasks: A test theoretical analysis. Perceptual and Motor Skills, 96, 1153-1172. • Voracek, M., & Formann, A. K. (2004). Variation in European suicide rates is better accounted for by latitude and longitude than by national percentage of Finno-Ugrians and Type O blood: A rebuttal of Lester and Kondrichin (2004). Perceptual and Motor Skills, 99, 1243-1250. • Formann, A. K. (2006). Mixture analysis of longitudinal binary data. Statistics in Medicine, 25, 1457-1469. • Formann, A. K. (2006). Testing the Rasch model by means of the mixture fit index. British Journal of Mathematical and Statistical Psychology, 59, 89-95. • Formann, A. K. (2007). Mixture analysis of multivariate categorical data with covariates and missing entries. Computational Statistics and Data Analysis, 51, 5236-5246. • Formann, A. K. (2008). Estimating the proportion of studies missing for meta-analysis due to publication bias. Contemporary Clinical Trials, 29, 732-739. • Formann, A. K., & Böhning, D. (2008). Re: Insights into latent class analysis of diagnostic test performance. Biostatistics, 9, 777-778. • Tran, U. S., & Formann, A. K. (2008). Piaget's water-level tasks: Performance across the lifespan with emphasis on the elderly. Personality and Individual Differences, 45, 232-237. • Voracek, M., Tran, U. S., & Formann, A. K. (2008). Birthday and birthmate problems: Misconceptions of probability among psychology undergraduates and casino visitors and personnel. Perceptual and Motor Skills, 106, 91-103. • Tran, U. S., & Formann, A. K. (2009). Performance of parallel analysis in retrieving unidimensionality in the presence of binary data. Educational and Psychological Measurement, 69, 50-61. • Formann, A. K. (2010). The Newcomb-Benford law in its relation to some common distributions. PLoS ONE, 5, e10541. • Voracek, M., Gabler, D., Kreutzer, C., Stieger, S., Swami, V., & Formann, A. K. (2010). Multi-method personality assessment of butchers and hunters: Beliefs and reality. Personality and Individual Differences, 49, 819-822. • Voracek, M., Tran, U. S., Fischer-Kern, M., Formann, A. K., & Springer-Kremser, M. (2010). Like father, like son? Familial aggregation of physicians among medical and psychology students in Austria. Higher Education, 59, 737-748. • Pietschnig, J., Voracek, M., & Formann, A. K. (2010). Mozart effect––Shmozart effect: A meta-analysis. Intelligence, 38, 314-323. • Pietschnig, J., Voracek, M., & Formann, A. K. (2010). Pervasiveness of the IQ rise: A cross-temporal meta-analysis. PLoS ONE, 5, e14406. • Nader, I. W., Tran, U. S., & Formann, A. K. (2011). Sensitivity to initial values in full non-parametric maximum-likelihood estimation of the two-parameter logistic model. British Journal of Mathematical and Statistical Psychology, 64, 320-336. • Pietschnig, J., Voracek, M., & Formann, A. K. (2011). Female Flynn effects: No sex differences in generational IQ gains. Personality and Individual Differences, 50, 759-762. • Stieger, S., Formann, A. K., & Burger, C. (2011). Humor styles and their relationship to explicit and implicit self-esteem. Personality and Individual Differences, 50, 747-750. • Stieger, S., Voracek, M., & Formann, A. K. (2012). How to administer the Initial Preference Task. European Journal of Personality, 26, 63-78. • Preinerstorfer, D., & Formann, A. K. (2012). Parameter recovery and model selection in mixed Rasch models. British Journal of Mathematical and Statistical Psychology, 65, 251-262. • Holling, H., Böhning, W., Böhning, D., & Formann, A. K. (2013). The covariate-adjusted frequency plot. Statistical Methods in Medical Research, 25, 902-916. Books • Formann, A. K., & Piswanger, K. (1979). Wiener Matrizen-Test. Ein Rasch-skalierter sprachfreier Intelligenztest [Viennese Matrices Test: A Rasch-scaled culture-fair intelligence test]. Weinheim: Beltz. • Formann, A. K. (1984). Latent Class Analyse: Einführung in die Theorie und Anwendung [Latent class analysis: Introduction to theory and application]. Weinheim: Beltz. • Formann, A. K., Waldherr, K., & Piswanger, K. (2011). Wiener Matrizen-Test 2 (WMT-2): Ein Rasch-skalierter sprachfreier Kurztest zur Erfassung der Intelligenz [Viennese Matrices Test 2: A Rasch-scaled language-free short test for the assessment of intelligence]. Göttingen: Hogrefe. == External links ==