2011

Normalize By
Enter a value or an expression if you want to normalize the data values
relative to some other data value. Click
to display the Choose Data
Expression dialog box.
Read Data
Reads the data from the data source according to the expression you defined.
Data Ranges area
Group Value By
Select a method for partitioning data values.
Optimal The optimal method groups data values based upon a determination
of the natural breaks in the data. Because the calculations are iterative, this
method quite literally finds the optimal sets of values in a group based upon
the position of values upon a number line. It is most useful for complex
non-uniform distributions where calculation time is less important than
the accuracy of grouping. This is the default method.
Quantile Divides the data so that each range contains an equal number of
values. Also known as equal count, this method is most appropriate where
the data values are linear (equally distributed).
Equal Interval Divides the data into a specified number of groups from the
minimum value to the maximum. Also known as equal step, this method
has the disadvantage that it may over generalize the data and place too
many values in one range and too few in another.
Standard Deviation This method calculates how far data values differ from
the arithmetic mean. It is most effective when the data approximates a
normal distribution (bell-shaped curve). This is rarely the case with
geographical data, but is fairly common when considering demographic
data. Because of this curve preference, standard deviations are best used
with an even number of groups. Standard deviations are often used to
emphasize how far a specific value is above or below the mean value.
Number
Select the number of ranges to create.
Precision
Specify the numeric precision. This option rounds the values up or down
to the decimal point you specify. Rounding only affects the range value
calculations and resulting range divisions. It does not affect the actual data
values stored in the data source. For more information, see Notes About
Precision below.
1630 | Chapter 22 Display Manager Dialog Boxes