Compute the Mahalanobis distance of each sample from the center of an N-dimensional principal component space.
object of class
integer scalar specifying the number of components to use when assessing QC.
The theory says that, under the null hypothesis that all samples arise from the same multivariate normal distribution, the distance from the center of a D-dimensional principal component space should follow a chi-squared distribution with D degrees of freedom. This theory lets us compute p-values associated with the Mahalanobis distances for each sample. This method can be used for quality control or outlier identification.
Returns a data frame containing two columns, with the rows
corresponding to the columns of the original data set on which PCA was
performed. First column is the chi-squared statistic, with
degrees of freedom. Second column is the associated p-value.
Kevin R. Coombes [email protected]
Coombes KR, et al.
Quality control and peak finding for proteomics data collected from nipple aspirate fluid by surface-enhanced laser desorption and ionization. Clin Chem 2003; 49:1615-23.
1 2 3 4 5
Add the following code to your website.
For more information on customizing the embed code, read Embedding Snippets.