Abstract

This document is a brief guide to mapping Census data in ArcMap and assumes that you have already created a map using Geolytics' CensusCD products in EDS. If you have not yet done so, please review documentation for working with CensusCD+Maps.

Geolytics' CensusCD products provide several detailed mapping options for US Census Data, including a data export feature to the following formats: ArcView (.shp), Bitmap (.bmp) and MapInfo (.mif).

In this example, we will create ArcView files using CensusCD+Maps and import the data into ArcMap.

Please note the use of the ArcGIS software in EDS is restricted to Columbia University affiliates (ID holders).

This guide covers the following steps for using ArcGIS:

• Creating an export file in CensusCD+Maps
• Importing the ArcView shapefile into ArcGIS
• Creating a thematic map
• Saving your work

Creating an export file in CensusCD+Maps

In this example, we will work with a Census tract map of New York county from CensusCD 2000 Short Form.

While in CensusCD 2000, click on the File menu, and choose Export. Then click on To ArcView's Shape. This automatically creates *.shp, *.shx, and *.dbf files. Because we had named our request file census in this example, our ArcView files are named census.shp, census.shx, and census.dbf.

Note: The *.shp, *.shx, and *.dbf files must all stay within the same directory for the shapefile to function properly.

Importing the Map into ArcGIS

• Start ArcMap by choosing Programs on the Start Menu and then selecting Mapping Software, ArcGIS , and ArcMap.
• Click on File, and then Add Data. Specify the directory and the *.shp file will appear on the screen. Click on Open. ArcMap will open the map, and the name of your file will appear in the layers box.

Creating a thematic map

• Right click on the file name under layers and select Properties, the Layer Properties window will appear
• In Layer Properties, click on Symbology, and then Quantities. This gives you the option to show ranges of data for each variable.
• Choose the variable you want to display in the Value pull-down menu within the Fields box.
• Also within this screen, you can change colors, number of ranges, classification method, and number of classes.
• When finished, click on Ok

Tip: Right clicking on file name in the layers screen will give you the option to Open Attribute Table, displaying the data file for the map.

Orient the Map: A map window may display only a limited section of the map you wish to view. You can use Tools toolbar to do the following:

Note: If the Tools toolbar is not visible, select: View > Toolbars > Tools

• Zoom-in: Select the positive magnifying glass tool and click on the area you wish to zoom-in on.
• Zoom-out: Select the minus magnifying glass tool and click on the area you want to zoom-out from.
• Move Map in Window: To look at a different section of a map using the current level of magnification, select the hand tool from the Main Toolbar. Move the hand to the part of the map window closest to the area you wish to view and drag it to the center of the window.

Labeling the features of your map

Displaying feature labels on a map is often quite important such as street names or tract numbers. There are two methods:

• To have ArcMap automatically display labels, right click on the filename in Layers screen, and choose Label Features.

• To choose what field is used for labeling and how labels are represented:
  • Right click on the layer and select Properties
  • Click on the Labels tab and make modifications and choices that best fit your needs.

If you wish to display labels for more than one layer, repeat the process and simply select a different layer in the Layer Control dialogue box.

Note: The degree of magnification affects labeling. The more you zoom-in the more detailed the labels. So if you don't find certain labels you want, zoom-in and try again.

Saving your work

Once you have finished adjusting the map to your needs, you'll probably want to walk away with a copy. Of course, you can simply print a copy here and now (i.e. in EDS).

To save a copy of your file in .pdf, .jpg, or another supported file format, please do the following:

• Choose File then Export Map

• Navigate to the directory you would like to save the file
• Choose the prefered format, and give the file a name
• Click on Options

• Make any adjustments regarding resolution, etc.
• Click on Export