
we measure one property, nuclear diameter, and this is the feature we call x.
It may be that the pdf of the diameter measurement, x, is already known for one
or both classes of cells. If not, we would have to estimate it by measuring a large
number of normal and abnormal cells and plotting histograms of their nuclear
diameters. After normalization to unit area and perhaps some smoothing, these
histograms can be taken as estimates of the corresponding pdfs. If the histogram
fits the Gaussian form, to a reasonable approximation, we can compute the
mean, m , and variance, s, and use the parametric representation for the normal
distribution
pxðÞ¼
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