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R- and Q-Analysis

  1. J. Edward Jackson

Published Online: 15 JUL 2005

DOI: 10.1002/0470011815.b2a10077

Encyclopedia of Biostatistics

Encyclopedia of Biostatistics

How to Cite

Jackson, J. E. 2005. R- and Q-Analysis. Encyclopedia of Biostatistics. 6.

Author Information

  1. Rochester, NY, USA

Publication History

  1. Published Online: 15 JUL 2005


The starting point for principal component analysis, factor analysis, or multidimensional scaling is an nxp data matrix representing n observations on p variables. In R-Analysis, a pxp matrix, such as a covariance or correlation matrix, is formed from which components or factors are obtained in terms of the variables. In Q-Analysis, the situation is reversed. The matrix is nxn and the components or factors are in terms of the observations. N-Analysis, also referred to as Singular Value Decomposition, operates on the data matrix directly and obtains results for both the variables and observations. In M-Analysis, the data matrix has been corrected for both its row and column means.


  • principal component analysis;
  • factor analysis;
  • singular value decomposition;
  • multidimensional scaling