Fig. 3.

Patchworks of correlation coefficients reveal global chemotopy with respect to functional group position for esters and alcohols. Each patchwork represents Pearson’s correlation coefficients obtained by correlating every pair of averaged data matrices within an odorant series. Individual isomers of heptanol (C7 alcohols) and nonanol (C9 alcohols) are identified by their substitution position. Individual esters are indicated by abbreviations: mc, methyl caproate; ev, ethyl valerate; pb, propyl butyrate; bp, butyl propionate; aa, amyl acetate. Global chemotopy is evident from the higher correlation coefficients for odorants substituted at adjacent positions (i.e., along the diagonal of the patchwork).