SVD decomposition (left panels), histogram of column correlations (center
panels), and condition number of randomly subselected set of columns (right panels), for
the eight described datasets. The results for a single medium/metal ion are shown on the
top, and the results for the 3 media/metal ions are shown on the bottom. (A–D) The
35 largest singular values of the associated A matrices. (B–E) The
distribution of the uncentered correlations between all pairs of columns in the
A matrix, estimated by performing 20000 random samples. (C–F) The
expected mean and standard deviation of the relative error for recovering population
weights from an arbitrary M=1,…,10 subset of columns.