Figure 3.
Consequences of multiplicative (correlated and uncorrelated) measurement error for data analysis. (A) Scatter plot of the overlayed view of the first two components of two PCA models of simulated data sets; one without multiplicative error and one with multiplicative error. For visualization purposes, the scores are plotted in the same graph, but the subspaces spanned by the first two principal components for the two data sets are of course different. The labels on both axes also present the percentage explained variation for the two analyses. (B) Loading plot for the error free data. (C) Loading plot for the data with multiplicative error. See Material and Methods section 6.5.3 for details on the simulations.