Pitney Bowes MapInfo Vertical Mapper - Manual (Page 60)

Understanding the Location Profiler Model
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Vertical Mapper 3.7
Shown here are six exclusion radius distance decay curves supported by the Location
Profiler. Values along the x-axis represent a ratio obtained by dividing the distance
between the grid point and data point by the exclusion radius. Curve 3 represents the
most typical exclusion radius decay function that can be applied to the widest variety of
modeling parameters.
The y-axis indicates the decay factor associated with the data point. This decay factor, which is
always between zero and one, is then multiplied by the weighting factor associated with the data
point to obtain the weighted value. This weighted value is then multiplied by the measured distance
between the grid point and data point, to obtain a weighted distance. The weighted average distance
for the grid point is obtained by summing all the weighted distances for each data point, then divided
by the sum of all the weighted values of the data points.
This figure shows the blending relationship between distance decay functions relating
to the exclusion zone and the search zone. A continuous function can be created by
choosing complementary curves that will distance weight all point locations lying
between the grid node and the search radius.