This guide has been largely reproduced from the Geolytics' CensusCD Blocks User Guide with permission from the authors.
Introduction
This document is intended to give a quick initiation plus some detailed explanations about the software and terminology. The help section on the CD has more detailed definitions of data terminology plus technical documentation from the Census Bureau to help make sense of the language of demographic statistics. A specific help section to explain the map viewer is available from both the main help contents and the map viewer itself.
A longer guide to this product, including everything here plus documentation on using the Map Viewer is available in PDF format. See the CensusCD+Maps plus the Map Viewer document.
A guide to the Census geography breakdown used by CensusCD and the way the data is gathered is available. See the document on CensusCD Geography and Data Info.
This guide is broken down into the following sections:
- General Information - details the steps in creating a map or report, and then walks through an example.
- Definition of Commands and Terminology - Reviews important pull-down menu commands and options.
General Information
File
The File menu commands let you establish a directory or path for naming and saving your output files. It controls where reports will be written and allows you to retrieve previous request parameters (i.e. the geographic and demographic selections).
New Request- used to start a new series of reports and controls the path/name of subsequent reports - if you don't use this function all reports and files will be given the default title of "Noname.*"
Open Request- opens existing, saved requests
Save request - saves current request parameters
Save Request As - used to start a new series of reports
Exit- Exits or quits the program
Extract and View Information
There are several different ways to extract and view the information held on CensusCD Blocks but the most basic menu commands are:
- Area: selects the overall geographic area for which you
want data
- Counts: chooses the demographic data of interest
These basic commands are needed to select the data for creating a report or a map. CensusCD Blocks includes two viewers for displaying and printing results - one for maps and one for data/text reports. The two commands above require you to make two choices common to most of the reports you'll create from CensusCD Blocks:
- Identify the large geographic area of interest that would be broken down to blocks
- Pick demographic data to extract
Example of How to Create a Map
The following section outlines the four steps necessary to create a map with an example. These steps are:- Select your Geographic Area of interest
- Choose the data you are looking for
- Run a Report or Map
- Customize your results
Select Your Geographic Area of Interest: The Geographic area screen will let you easily select blocks at any of the six geographical levels (Nation, Region, Division, State, County, and Tract/BNA). Simply select the geographical area you want from the pull down list. Note: If you only want blocks for a specific zip code within a county that you have selected, see the description of the Filter function below.
You can select any area and up to 240 areas of the same type. For example, several states like Texas, Arizona and Ohio or a number of counties like Bronx, Kings, and Queens in New York could be selected.
Important: YOU DO NOT WANT TO MAP CENSUS BLOCKS FOR ANYTHING LARGER THAN A COUNTY. For example, the block map is around 275 K polygons for the New York State, and the map would look like mush. However, you can get a list by running DBF or ASCII files for units larger than county.
Let's pick Manhattan as the area you want Block information for. To select Manhattan (New York County) as the area, you would:
- Select the menu item AREA
- Select GEOGRAPHIC AREA from the pull down list that will appear
- Select COUNTIES as the Geographic Area
- In the geographic areas window that will appear, select NEW YORK as the state
- Select NEW YORK as the county
- Select DONE
Please note most of the menu commands in CensusCD Blocks are also on the toolbar.
In this case when we select New York County we break it into the very small units known as Census Blocks which are the smallest geographical units the Census Burea uses. Our demographic data of interest is Total Persons in Occupied Household unit which we can select as an individual variable.
HINT: You can find micro help at the bottom of any screen which will suggest the remaining steps needed to create a report. (Screen shots below have been cropped for size.)
3) Choose the data you are looking for - The Counts menu is where specific demographic data is chosen. Counts are the actual block demographic or identification data that you want to know.
For example:
- In the COUNTS window that appears with all Block demographics, scroll down and select Total Persons in Occupied Household Unit.
- Select DONE.
While in the COUNTS screen, simply select the demographics you want. You know a count is selected when you see its short description in the SELECTED COUNTS window. A series of counts can be selected by tagging the first and last counts in this series, and then tagging the SELECT BETWEEN button.
A file called "fields.lst" contains full description of all demographic data (128 variables) on Counts. This file can be found through Windows Explorer (f:\program files\CCDBlocks\fields.lst) or clicking to VIEW, and then FILES command, and looking in .lst files.
4) Run a Report or Map - The last step is to run the file. First choose, ASCII, DBF, or Map.
For example, let's map it:
- Select the menu item RUN,
- Select MAP
After selecting Map from the run menu CensusCD Blocks creates a .dbf file based on our previous geographic/data selections. It then automatically launches a map viewer to display the data from that .dbf file. The resulting map looks like this:
5) Customize your results - Within the map viewer you can change data themes, ranges, and color schemes. The map viewer will let you print out your map (along with options to include a legend, the file name, and a second title) or save it as a .bmp file which can be imported or pasted into most word processing, spreadsheet, and graphics packages. CensusCD Blocks also lets you export boundaries and data in desktop mapping formats (ArcView or MapInfo). There is even a calculator for creating and displaying virtual variables based on data in your report.
You can use the tools to navigate through and customize the map.
The Area tab will list all of the smaller areas displayed
in the map.
The Record tab will show all of the data available in the
report and let you change the displayed data theme.
The Stat tab will customize the data's thematic display.
The Log tab will keep track of the changes you've made.
There are options to change color schemes, re-center map, resize map,
create new variables, export maps, and much more. See the help section
specific to the Map Viewer for more detailed information.
HINT: You can even use the Map Viewer to display your own .dbf data files if you have an area key which lets the program match boundaries to your data records.
You can also select DBF and ASCII file in order to view data file. While browsing the file you can search for information, copy to clipboard, or print the file:
HINT: You can easily read tract number, block groups, and blocks fromthe .dbf file even if you did not include them in counts option. Let's take the example of the first line in the dbf file; 36061000101101. The breakdown of this number is as follows:
36= State, 061= county, 000201= tract, 1= Block Group, 01= BlockFinally, you can use the file data as an input to other applications such as statistical (e.g. SAS, SPSS), database(e.g.Access, Oracle), or mapping (e.g. ArcView, MapInfo) packages.
Other Useful Commands
This section will review some important pulldown command options from the CensusCD Block screen including:Radius
Radius creates a circular area or creates a circular area around a circle (called a doughnut area). You may decide to use this type of area view to get information for what's around a specific location. Use exact Latitude or Longitute to specify the center of the Radius. Then enter the Distance from the center of the radius to specify the radical area size (for example, 10 miles from a specific location).
Latitude/Longitude - Exact coordinates are matched to the center points of surrounding areas for any level of geography
Filter
The Filter command allows Blocks for the area selected, to be further limited. Filter can limit Blocks accourding to a user defined demographic profile. For example, you want only Blocks with more than 75% Hispanic population to be in the file. The filter expression will be:
(HisPop/Pop)*100.0)>75.0
Housing value greater than $100,000:
MeanVal>100,000
The filter function can also be used to limit Blocks to a specific geographic area, such as: Zip, Place, MSA, HUC, MCD, CDD, etc. Using our example above, if you only wanted blocks for zip-code 10001 in Manhattan, after selecting Manhattan as the area, you would enter a Filter of:
ZIP=`10001'
Suppose you wanted the blocks for the place of Palm Beach Florida, and you did not know what the Place code to Filter on was, use the Search Areas. First select Palm Beach County, Florida. Then select Filter, and Search Areas. Every occurence of Palm Beach in the US will be displayed. Select "FL, Palm Beach town," and this will format the filter of:
PlaceFP=`54205'
Search Areas will search thru Zip, MCD, Place, County, MSA/CMSA, PMSA, Urban, Indian reservations, and ANRC codes. A directory called \CODES is on the Blocks CD-ROM contains codes for HUC, and VTD's.
View
View opens previously created maps or reports.
You can also use file option in View command to view the count list documentation (fields.lst).\CODES directory in file option contains codes for HUC, and VTD's.
Help
CensusCD Blocks contains extensive on-line help. You may rely on "automatic advice" located on the bottom of the screen for `next step' prompting. Help can also be requested by placing the focus on the item in question, and pressing the F1 key.
