PolicyMap offers a large selection of variables about communities. In addition to business data, there are are also variables that cover many aspects of housing, lending, income, health and quality of life. These variables have been collected by The Reinvestment Fund, "a nonprofit community development financial institution that works across the Mid-Atlantic". Browse their wide selection of variables to get a sense of the time periods and locations covered, as some of the coverage can be for a relatively small area.
You can reach Yale's PolicyMap subscription at yale.policymap.com/maps. If you do not want everyone at Yale to have access to your data, you will need to create an individual PolicyMap account. These accounts are free with the Yale site license.
PolicyMap allows you to create custom regions that you can use for analysis. These areas are saved and are one of the geographic options when you create reports. There are three ways to create regions:
Draw Custom Region
As the instructions will tell you, to Draw a Custom Region you just have to click points on the map until you have the shape you want, and then click on the first point again to close the polygon.
Assemble Custom Region
You can assemble a custom region from existing boundaries. In addition to the standard census boundaries like tracts and block groups, you can also choose to create a region based on School Districts, Congressional Districts or Community Development Block Grant (CDBG) areas. All of the regions you choose will have to be of the same type.
The Radius Region option allows you to etiher type in an address or click a point on the map, choose a radius, and then create an area based on those two pieces of information.
The variables available in PolicyMap are organized into categories available as tabs at the top of the map window. Inside the main categories are subcategories, organized by whether the data will be displayed as Data Layers, where the variable will be represented as different colored areas on the map (a choropleth map), or Data Points, where the data are shown as distinct points on the map.
In the main map window, you can choose one variable that is displayed as a Data Layer and multiple variables are displayed as Data Points to view in your map at the same time. Each of the variables shown as Data Points will appear with a different symbol, which can't be changed. You can reduce the number of points by clicking on the "Filter Points" button and choosing the attribute that you want to use to narrow down the points, followed by the value that you are interested in. An example of this is displaying the Public Schools location variable and then only showing schools that have a "Grades Offered" value of "12". Now only schools that offer grade 12 will be shown on the map.
You can change the color of the Data Layer using the "Edit>Colors" menu and choosing one of the pre-defined color ramps. You can also use "Edit>Ranges" to manually change the number of ranges used for the data, as well as the break points.
If you want to use Data Layers to filter your data, you can create a 3-Layer Map. Choose 3-Layer Maps in the bar at the very top of the screen. You will be able to add 3 Data Layers to the map, and the addition of each layer will filter the geographic areas that you see. This can be done in any of the geographic levels (State down to Census Tract) if those geographic levels are available for that variable. Once you have chose the variables you can limit the values using the minimum and maximum boxes in the Data Layers menu.
The Data Loader allows you to add data to a map in PolicyMap, either by putting the points on the map individually (Add Points Directly to the Map) or uploading a spreadsheet of points (Upload Spreadsheet of Points).
If you choose to add points to the map you will be asked to name your dataset, share it with all Yale users (unless you get a personal login) and to choose an icon. You can then create your dataset. If it tells you that there is a problem creating your dataset, it may be because the name for your dataset has already been used by someone else at Yale - try given using a different name. Once your dataset is created, a bar will appear in the top of the map window. You can Enter Address for Site and it will place the icon in the appropriate place, or you can click on the map to add points. When you are finished, you can Save your dataset or you can Download Points as a csv, with the Title, Description, Image and latitude and longitude.
If you add a spreadsheet of addresses to the map, PolicyMap will place icons on the map at those address and add the latitude and longitude information to the table for you.
Any data you create using the Data Loader will be available to anyone at Yale. Please see the box at the top of this guide for information on getting a private, personal login.