BrainSpectra {MetabolAnalyze}

NMR spectral data from brain tissue samples.

Description

NMR spectral data from brain tissue samples of 33 rats, where each tissue sample originates in one of four known brain regions. Each spectrum has 164 spectral bins, measured in parts per million (ppm).

Usage

data(BrainSpectra)

Format

A list containing

1. a matrix with 33 rows and 164 columns

2. a vector indicating the brain region of origin of each sample where:

   • 1 = Brain stem

   • 2 = Cerebellum

   • 3 = Hippocampus

   • 4 = Pre-frontal cortex

Details

This is simulated data, based on parameter estimates from a mixture of PPCA models with 4 groups and 7 principal components fitted to a similar real data set.

Source

Nyamundanda, G., Gormley, I.C. and Brennan, L. (2010) Probabilistic principal components analysis for metabolomic data. Technical report. University College Dublin, Ireland.