Pitney Bowes MapInfo Professional - Manual (Page 273)

Creating a Thematic Map
There are many kinds of thematic maps, but the process for creating each type of map is the same. In
this section, we cover the creation of thematic maps in general terms.
You can find more specific instructions for creating specific types of thematic maps in the Help System.
Step 1 - Choosing a Type of Thematic Template
Templates allow you to make a thematic map based on values and settings. In our default types, you
can alter these settings and/or save them as a new template you can use again. When you first create
a thematic map, you select a template that you can modify to suit your requirements. You cannot create
a theme without using an existing theme template.
• Template Sort by Name - Displays available templates in alphabetical order according to their name.
• Template Sort by Time - Displays available templates according to the time they were created or last
modified.
• Preview Legend Sample (Template Type) - Displays a sample legend for the template type.
• Use Customized Legend Text - Displays customized text for the legend. If enabled, the template
has custom titles or range labels. Check to use the custom text.
• Cancel Button - Cancels the options dialog box and returns to the map.
• Next Button - Continue to next step.
• Range Template - Displays your data according to the ranges you set. Ranges are shaded with colors
and/or patterns. Choose from templates displayed as shaded lines, points or regions. Ranged thematic
maps allow you to illustrate data values across points, lines and regions. They are used to show a
relationship between the data values and geographical area (e.g. sales figures, household income)
or to present ratio information such as population density (population divided by area). Ratio information
can be shown in other types of thematic maps when you choose Expression in Step 2.
• Bar Chart Template - Displays a bar chart of your thematic variables for each record in your table.
Use bar charts to analyze multiple variables per record on the map. Make comparisons between the
size of the bars in each chart to obtain information about a record in the table set, or compare one bar
in all the bar charts to draw conclusions about a variable across all of the records, or compare the
height of the bar charts to obtain information about the entire table. To indicate a negative value in a
bar chart, bars extend in the direction opposite to the charts orientation. Negative values do not display
in stacked bar charts.
• Pie Chart Template - Displays a pie chart of your thematic variables for each record in your table.
Pie charts are multi-variable. Use pie charts on the map to analyze more than one variable at a time.
You can compare the size of the pie wedges in each chart to obtain information about a record in the
table, or compare one pie wedge in all of the pie charts to draw conclusions about a variable across
all the records, or compare the diameter of the pie charts to obtain information about the entire data
set.
• Graduated Template - Displays a symbol for each record in your table, the size of which is directly
proportional to your data values. A graduated symbol map shows data points with specific numerical
values. It is useful for illustrating quantitative information, such as high-to-low rankings. The size of
the symbols is proportional to the data values of the points. Points that have larger data values appear
larger, and points that have smaller data values appear smaller.
For instructions on creating a Graduated Symbols thematic map, see Creating a Graduated Symbols
Map in the Help System.
• Dot Density Template - Displays the data values as dots on your map, where each dot is equal to a
number, and the total number of dots in a region is proportional to the data value for that region. A dot
density map allows you to examine raw counts of data (e.g. population). Each dot represents a number
273 MapInfo Professional User Guide
Chapter 10: Creating Thematic and Other Themed Maps