Method
Choose an option from the Method drop-down list to select how the ranges are created. Choose from six different methods:
Equal Count
Each range contains approximately the same number of records. If the number of records is not evenly divisible by the number of ranges, MapInfo Pro places the remaining records into the most appropriate ranges.
Equal Ranges
The difference between the top and bottom values in each range is the same.
Natural Break
The range breaks are determined according to an algorithm such that the difference between the data values and the average of the data values is minimized on a per range basis. This reduces error and enables you to obtain a truer representation of your data.
Standard Deviation
The middle range breaks at the mean of your data values, and the ranges above and below the middle range are one standard deviation above or below the mean.
Quantile
Determines the distribution of a variable across a segment of your data (e.g. population). When you choose Quantile, a Quantiling box appears at the bottom of the dialog box. Choose the field or an expression you want to perform the quantiling operation on from the drop-down list.
Custom
Indicates that the ranges are user-defined. When you choose Custom, a Custom Ranges box appears at the bottom of the dialog box. Highlight the range you want to change from the list in the middle of the dialog box, and edit the minimum and maximum values in the Custom Ranges box.
# of ranges
Choose the number of ranges you want from the drop-down list. The minimum number of ranges is 2, and the maximum number of ranges is 16. The default is 4 ranges.
Round by
Choose a rounding factor for the range breaks from the drop-down list. Each rounding factor is a multiple of 10.
>= Min
Indicates the inclusive lower bound of the range. The data values in the range interval are greater than or equal to the minimum value of the range.
The range intervals are displayed so that the minimum value of one range, and the maximum value of the range above it in the list box, are the same number. The records that have that value are counted in the range interval where the value represents the minimum value.
For example, one range is 26.2 to 30.9, and the range below it is 30.9 to 31.8. The record (or records) with the value 30.9 is counted in the range interval, 30.9 to 31.8, because 30.9 represents the minimum value in that range interval.
< Max
Indicates the exclusive upper bound of the range. The data values in the range interval are less than the maximum value of the range, with the exception of the last range, where the values are <= to the maximum value. For example, you have four ranges and the values in the fourth range are 30-40. A data value of 40 falls into the last range.
%
Indicates the percentage of the total number of records in the range.
#
Indicates the number of records in the range.
Recalc
Whenever you change a setting with any of the controls explained above, the OK button becomes a Recalc button, and the list box displays this message:
Press <Recalc> button to Recalculate ranges.You can make several changes at once before doing a recalculation. Recalculations can be time consuming; depending on the data set and range method you are using.
Cancel
Cancels your customizing and returns you to the Create Thematic Map - Step 3 of 3 Dialog Box.
OK
MapInfo Pro customizes your map according to your specifications and returns you to the Create Thematic Map - Step 3 of 3 Dialog Box.
See Also: