The American Psychological Association defines Quantitative Psychology as "the study of methods and techniques for the measurement of human attributes, the statistical and mathematical modeling of psychological processes, the design of research studies, and the analysis of psychological data".
Quantitative Psychology specializes in the measurement, methodology and research design and analysis relevant to data in the social sciences. "The Research in study of Quantitative psychology develops psychological theory in relation to mathematics and statistics. Elaborating the existing methods and developing new concepts, the quantitative psychology involves much more than "applications" of statistics and mathematics." 
Quantitative psychology has two major subfields, psychometrics and mathematical psychology. Research in psychometrics develops methods of practice and analysis of psychological measurement, for example, developing a questionnaire to test memory and methods of analyzing data from that questionnaire. Research in mathematical psychology develops novel mathematical models that describe psychological processes.
Quantitative psychology is served by several scientific organizations. These include the Psychometric Society, Division 5 of the American Psychological Association (Evaluation, Measurement and Statistics), the Society of Multivariate Experimental Psychology, and the European Society for Methodology. Associated disciplines include statistics, mathematics, educational measurement, educational statistics, sociology, and political science. Several scholarly journals reflect the efforts of scientists in these areas, notably Psychometrika, Multivariate Behavioral Research, Structural Equation Modeling and Psychological Methods.
In August 2005, the APA expressed the need for more quantitative psychologists in the industry—for every PhD awarded in the subject, there were about 2.5 quantitative psychologist position openings. Currently, 23 American universities offer Ph.D. programs in quantitative psychology within their psychology departments (and additional universities offer programs that focus on but do not necessarily encompass the field). There is also a comparable number of Master-level programs in quantitative psychology in the US.
- Quantitative Psychology
- Quantitative Psychology — UCLA Psychology Department: Home
- Quantitative Psychology For Measuring The Human Attributes
- Mathematical Psychology
- Report of the Task Force for Increasing the Number of Quantitative Psychologists, page 1. American Psychological Association. Retrieved February 15, 2012
- Introduction to Quantitative Psychology page 2. American Psychological Association. Retrieved February 15, 2012.
- Graduate Studies in Psychology