Minimal spanning tree (MST) planing is also known as multivariate
planing. MST planing is similar in intent to
multidimensional scaling (MDS) onto a 2-dimensional plane,
which tries to find N points in a 2-dimensional plane such
that the inter-point distances in the plane match the inter-point
distances in high-dimensional space. MST planing is much
faster to compute than MDS because it requires fewer calculations.
Planing 40,000 points is a perfectly
reasonable task.
Principal component analysis is just "poor man's MDS."
The following 2 plots are the result of MST planing of 3011 points
from an 8-dimensional space. Red points are cells not treated with
etoposide; blue points are cells treated with etoposide.
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| MST planing displayed as a scatterplot |
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| MST planing displayed as a variable resolution bivariate plot |