HP Intelligent Management Center Standard Software Platform - Manual (Page 392)

very distorted representation of the data. A more useful map would have
ranges like 0-5000, 5000-10000, 10000-15000, 15000-20000, and over
20000. It is important to carefully define your ranges.
Note:
The end value for each division is repeated as the start value for the next
division; the actual value is included in the group it starts. That is, the ranges
in the previous example are actually: 0-4999, 5000-9999, and so on.
There are four different distribution methods for ranged maps.
• Equal count
This option assigns intervals in such a way that the same number of
regions (or as close to the same number of regions as possible) appear
in each interval. In other words, this option would assign intervals so that
each color on the map is assigned to the same number of regions. The
numeric quantity of the summary values in each interval may or may not
be equal, depending on the individual regions and their summary values.
• Equal ranges
This option assigns intervals in such a way that the summary values in
each interval are numerically equal. The number of regions in each interval
may or may not be equal, depending on the individual regions and their
summary values.
• Natural break
This option assigns intervals using an algorithm that attempts to minimize
the difference between the summary values and the average of the
summary values for each interval.
• Standard deviation
This option assigns intervals in such a way that the middle interval breaks
at the mean (or average) of the data values, and the intervals above and
below the middle range are one standard deviation above or below the
mean. Standard deviation is the square root of the variance. It projects
how various values in a set of values deviate from the mean for that set.
Dot Density
A Dot Density map displays a dot for each occurrence of a specified item.
For example, you might create a United States map that shows one dot for
each shipbuilder in the nation. In states like Tennessee, there would be no
392 Crystal Reports 2008 SP3 User's Guide
Mapping 15
Mapping concepts