GEOG 482 Project 2: Mapping the Census

Dillsburg, York County, Pennsylvania

Don Krysakowski

In addition to the Census features, this map shows the major geographical road and stream features of  northern York County with Adams County to the southwest and Cumberland County to the west and north.  The cross-hatched areas are the urbanized areas (UA) of a central place (in this case Harrisburg, PA) that have a population density of at least 1000 people per square mile of land area that when taken together has a residential population of at least 50,000 people (U. S. Bureau of theCensus, 2003).

The map scale is 1:146215 or one inch equals approximately 2.31 miles.

The map was generated from the U. S. Census Bureau's American FactFinder web site and its Topologically Integrated Geographic Encoding and Referencing (TIGER) database and mapping service.  This thematic map was created from TIGER/Line files integrated with the U.S. Bureau of the Census attribute data Census 2000 Summary File 1 (SF 1) 100-Percent Data (U. S. Bureau of the Census, 2003).

The map demonstrates that the highest concentration of people in the county is in City of York (in the center of the county), with generally lower population densities radiating away from York along its major arterial highways.  The high density area in the southwest corner of the county is the city and suburbs of Hanover, Pennsylvania, and the moderate population densities in the northern part of the county are the suburbs of Harrisburg, Pennsylvania.

The map scale is 1:487,384 or one inch represents approximately 7.69 miles.

Using the thematic mapping capability on the U. S. Census Bureau's American FactFinder web site that utilizes TIGER/Line files integrated with census data, I wanted to test this study finding for the Harrisburg area.  I first created two maps using TIGER/Line files and U. S. Bureau of the Census Summary File data (1990 and 2000 SF1 data), one based on 1990 Census data and the other based on 2000 Census data (U. S. Bureau of the Census, 2005).  These two maps show the population density of the townships in the counties surrounding Harrisburg, Pennsylvania.  Each township is categorized into one of seven categories by population density ranging from lowest (lightest) to highest (darkest). The categories are quantile based meaning that each category (not each township) has roughly an equal number of people in it.  When examining these two maps, labeled Exhibit 1, 1990 Population Density Surrounding Harrisburg, PA, and Exhibit 2, 2000 Population Density Surrounding Harrisburg, PA, we can see there there is virtually no difference.

Exhibit 1 (Above):  1990 Population Density Surrounding Harrisburg, PA.

Exhibit 2 (Above):  2000 Population Density Surrounding Harrisburg, PA.

From these maps, it would be difficult to apply the Brookings study findings to the Harrisburg area.  The population density of the city and the surrounding areas is virtually unchanged over the 10 year period from the 1990 Census to the 2000 Census.

However, utilizing the same TIGER/Line File data and the same U. S. Bureau of the Census Summary File data (1990 and 2000 SF1 data), I created two maps based showing the per capita income of the townships surrounding Harrisburg.  Exhibit 3 shows the 1990 Per Capita Income data and Exhibit 4 shows the 2000 Per Capita income data.

Exhibit 3 (Above):  1990 Per Capita Income for Townships Surrounding Harrisburg, PA.

Exhibit 4 (Above):  1990 Per Capita Income for Townships Surrounding Harrisburg, PA.

With the addition of these two maps, we can see that while the population density has remained relatively stable the per capita income in the townships surrounding Harrisburg has increased dramatically in the areas beyond the immediate Harrisburg suburbs.  Further, the per capita income of the city of Harrisburg actually fell relative to its suburban neighbors.  In general, while the population density of the suburbs has not grown significantly, the suburbs have become significantly wealthier than the Harrisburg city central core.  This second analysis then, does tend to support one of  the Brookings study's conclusions that the focus of the state's economic (my emphasis) growth is shifting decisively toward outlying communities.

Finally, rather than discount the 1990 dollar categories to their 2000 equivalents, or vice versa, I used a quantile distribution of per capita dollars.  I have made the assumption that the relative distribution of dollar values for each quantile in each census are roughly equivalent even if the real dollar values are different.  Further, I used the maximum of seven categories for this data class in an effort to show the greatest visual difference and variability among the townships.  Each map scale is identical, 1:487,384 or one inch represents approximately 7.69 miles.