title: ppcor: An R Package for a Fast Calculation to Semi-partial Correlation Coefficients.
abstract: Lack of a general matrix formula hampers implementation of the semi-partial correlation, also known as part correlation, to the higher-order coefficient. This is because the higher-order semi-partial correlation calculation using a recursive formula requires an enormous number of recursive calculations to obtain the correlation coefficients. To resolve this difficulty, we derive a general matrix formula of the semi-partial correlation for fast computation. The semi-partial correlations are then implemented on an R packageppcoralong with the partial correlation. Owing to the general matrix formulas, users can readily calculate the coefficients of both partial and semi-partial correlations without computational burden. The packageppcorfurther provides users with the level of the statistical significance with its test statistic.
authors.affiliation: Biostatistics Core, Karmanos Cancer Institute, Wayne State University.
authors.forename: Seongho
authors.initials: S
authors.lastname: Kim
keywords: correlation; part correlation; partial correlation; ppcor; semi-partial correlation