Contribution Plots in PCA - Discovering Why Points Are Outliers
Jan 10, 2017 2:51 AM(2794 views)
When using PC Analysis in JMP I would find it very useful to know what contribution a single point or points have compared to others. In other programs ( SIMCA) this is available as a 'Contribution plot' and is quick and easy to use and interpret.
This analysis method doesn't appear in JMP and I wondered if anyone else has used it and can share it as an add-in. Finding out why a sample/ measurement is different to another can be very useful for discovering the reasons for the observation being an outlier.
example which shows the type of graphic I'm after in JMP from 'Principal component analysis' by Rasmus Bro a and Age K. Smilde ab
You can get some of the same functionality using two-way clustering in JMP (Put the same columns in the clustering platform, and then pick Two-way clustering from the hotspot. You may also want to turn on colour clusters and alter the number of groups). Rather than bars with length you are relying on a coloured 'bar code'.