Solution 4.6 - Chemometrics: Data Analysis for the Laboratory and Chemical Plant

1. The distance matrix is as follows

2. The five closest neighbours are listed below.

3. There appears a clear difficulty with sample 2. Sample 10 may have problems also, but is not so obviously mis-classified. Because the groups are fairly small a mis-classified sample can have a reasonably significant effect. It would be possible to repeat the modelling removing any doubtful sample.