Psychological statistics is application of formulas, theorems, numbers and laws to psychology. Statistical methods for psychology include development and application statistical theory and methods for modeling psychological data. These methods include psychometrics, factor analysis, experimental designs, and Bayesian statistics. The article also discusses journals in the same field.
Psychometrics is a field of study within psychology concerned with the theory and technique of measurement. Psychometrics generally refers to specialized fields within psychology and education devoted to testing, measurement, assessment, and related activities. Psychometrics is concerned with the objective measurement of latent constructs that cannot be directly observed. Examples of latent constructs include intelligence, introversion, mental disorders, and educational achievement. The levels of individuals on nonobservable latent variables are inferred through mathematical modeling based on what is observed from individuals' responses to items on tests and scales.
Monte Carlo methods, or Monte Carlo experiments, are a broad class of computational algorithms that rely on repeated random sampling to obtain numerical results. The underlying concept is to use randomness to solve problems that might be deterministic in principle. They are often used in physical and mathematical problems and are most useful when it is difficult or impossible to use other approaches. Monte Carlo methods are mainly used in three problem classes: optimization, numerical integration, and generating draws from a probability distribution.
Cronbach's alpha, also known as rho-equivalent reliability or coefficient alpha, is a reliability coefficient and a measure of the internal consistency of tests and measures.
Classical test theory (CTT) is a body of related psychometric theory that predicts outcomes of psychological testing such as the difficulty of items or the ability of test-takers. It is a theory of testing based on the idea that a person's observed or obtained score on a test is the sum of a true score (error-free score) and an error score. Generally speaking, the aim of classical test theory is to understand and improve the reliability of psychological tests.
In statistics, an effect size is a value measuring the strength of the relationship between two variables in a population, or a sample-based estimate of that quantity. It can refer to the value of a statistic calculated from a sample of data, the value of a parameter for a hypothetical population, or to the equation that operationalizes how statistics or parameters lead to the effect size value. Examples of effect sizes include the correlation between two variables, the regression coefficient in a regression, the mean difference, or the risk of a particular event happening. Effect sizes complement statistical hypothesis testing, and play an important role in power analyses, sample size planning, and in meta-analyses. The cluster of data-analysis methods concerning effect sizes is referred to as estimation statistics.
Construct validity concerns how well a set of indicators represent or reflect a concept that is not directly measurable. Construct validation is the accumulation of evidence to support the interpretation of what a measure reflects. Modern validity theory defines construct validity as the overarching concern of validity research, subsuming all other types of validity evidence such as content validity and criterion validity.
Quantitative psychology is a field of scientific study that focuses on the mathematical modeling, research design and methodology, and statistical analysis of psychological processes. It includes tests and other devices for measuring cognitive abilities. Quantitative psychologists develop and analyze a wide variety of research methods, including those of psychometrics, a field concerned with the theory and technique of psychological measurement.
Lee Joseph Cronbach was an American educational psychologist who made contributions to psychological testing and measurement.
In statistics, inter-rater reliability is the degree of agreement among independent observers who rate, code, or assess the same phenomenon.
Nambury S. Raju was an American psychology professor known for his work in psychometrics, meta-analysis, and utility theory. He was a Fellow of the Society of Industrial Organizational Psychology.
Anne Anastasi was an American psychologist best known for her pioneering development of psychometrics. Her generative work, Psychological Testing, remains a classic text in which she drew attention to the individual being tested and therefore to the responsibilities of the testers. She called for them to go beyond test scores, to search the assessed individual's history to help them to better understand their own results and themselves.
Psychometric software is software that is used for psychometric analysis of data from tests, questionnaires, or inventories reflecting latent psychoeducational variables. While some psychometric analyses can be performed with standard statistical software like SPSS, most analyses require specialized tools.
Statistics education is the practice of teaching and learning of statistics, along with the associated scholarly research.
Abelson's paradox is an applied statistics paradox identified by Robert P. Abelson. The paradox pertains to a possible paradoxical relationship between the magnitude of the r2 effect size and its practical meaning.
The Journal of Modern Applied Statistical Methods is a biannual peer-reviewed open access journal. It was established in 2002 by Shlomo Sawilowsky, and is currently published by the Wayne State University Library System in Detroit, MI. The Current Index to Statistics classifies it as one of over 160 core statistics journals. The journal originally appeared as a print and electronic journal through volume 8(1) in 2009, and subsequently as an electronic journal only. It publishes peer-reviewed work pertaining to new statistical tests and the comparison of existing statistical tests; bootstrap, Jackknife, and resampling methods; nonparametric, robust, permutation, exact, and approximate randomization methods; and statistical algorithms, pseudorandom number generators, and simulation techniques. The journal is indexed in the Elsevier Bibliographic Database, EMBASE, Compendex, Geobase, PsycINFO, ScienceDirect, and Scopus. It is also listed in the Encyclopedia of Measurement and Statistics and Cabells.
In statistics, one purpose for the analysis of variance (ANOVA) is to analyze differences in means between groups. The test statistic, F, assumes independence of observations, homogeneous variances, and population normality. ANOVA on ranks is a statistic designed for situations when the normality assumption has been violated.
Howard Charles Wainer is an American statistician, past principal research scientist at the Educational Testing Service, adjunct professor of statistics at the Wharton School of the University of Pennsylvania, and author, known for his contributions in the fields of statistics, psychometrics, and statistical graphics.
The Solomon four-group design is a research method developed by Richard Solomon in 1949. It is sometimes used in social science, psychology and medicine. It can be used if there are concerns that the treatment might be sensitized by the pre-test. In addition of the usual two groups, it has a second pair of groups who do not receive a pre-intervention evaluation. The structure of the trial is shown in the table :
Edna Schechtman was an Israeli statistician, a professor emeritus of statistics at the Department of Industrial Engineering and Management, Ben-Gurion University of the Negev. She is best known for development of statistical tools that utilize the Gini Mean Difference (GMD) as the measure of association.
