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Factor Analysis, Overview

  1. Ian T. Jolliffe

Published Online: 15 JUL 2005

DOI: 10.1002/0470011815.b2a13024

Encyclopedia of Biostatistics

Encyclopedia of Biostatistics

How to Cite

Jolliffe, I. T. 2005. Factor Analysis, Overview. Encyclopedia of Biostatistics. 3.

Author Information

  1. University of Aberdeen, Aberdeen, UK

Publication History

  1. Published Online: 15 JUL 2005


Factor analysis is a latent variable technique. It reduces the dimension of a data set by assuming that underlying the measured variables is a smaller number of unobservable factors. The measured variables are assumed to be linearly related to the factors, apart from an error term. There are many ways of estimating the loadings that relate the variables to the factors, and predicting the scores of the factors themselves. Solutions are typically nonunique, and are made as “simple” as possible by means of rotation of loadings. Much of factor analysis has been developed within psychology, but it is useful more widely. The technique is often used in an exploratory or descriptive manner, but confirmatory versions are also available.


  • factor loadings;
  • factor scores;
  • latent variables;
  • principal components analysis;
  • psychology;
  • rotation;
  • simple structure