Effective Comparative Analysis

There is no one best method of examining/analyzing different geographic areas based on demographic-economic characteristics. In this section three methods are compared, each having its own strengths and weaknesses. These methods are among yet others that can be reviewed in future posts.

Comparative analysis methods reviewed here are:
• Geographic maps
• Side by side comparative analysis
• Spreadsheets

In this post, these methods are compared in context of examining characteristics of school districts. But we use these same methods to examine cities, counties, census tracts, ZIP codes, legislative districts … among many other geographies. Applications reviewed here are for the Atlanta, GA school district and Fulton County, GA school district.

Geographic maps — Lay of the Land
Maps provide the relative geographic view — the lay of the land — typically not available via tabular display of data. The following view shows the district boundary (bold blue boundary). Click graphic for larger and more detailed view. Fulton County school district is the two separate sections shown as orange crosshatch pattern; Atlanta school district is shown as blue crosshatch pattern. Fulton County, defined as the county subdivision of Georgia, covers the same ground as the combination of Atlanta and Fulton County school districts. These geographic relationships cannot be effectively understood without maps.

Views developed using ProximityOne CV XE GIS software.

Side by side comparative analysis profiles
How do measures of economic prosperity compare between the districts? educational attainment?  Linguistic isolation?  Compare/contrast demographic-economic characteristics of the areas using four side-by-side comparative analysis profiles (CAPs):
General Demographics
Social Characteristics
Economic Characteristics
Housing Characteristics
One example — click the Economic Characteristics link.  The side by side profile appears.  On the new page, the CAP view, scroll down to “INCOME & BENEFITS ” and items E051.  Here the distribution of households by household income can be viewed; easily comparing patterns between the areas.  Easily select and compare among multiple measures. It can be seen that the Atlanta school district median household income (MHI) is $46,146 compared to Fulton County school district MHI of $68,238 — but at the same time the dollar and percent distribution of households by income can be effectively compared.

Examine other side-by-side CAPs of interest.  These insights cannot be gained from the maps alone.  Yet the side-by-side CAPs still are not able to show how these districts relate to other Georgia districts (or other geography such as counties).  Consider the role of the spreadsheet interactive tables.

View other school district comparative analysis profiles.

Spreadsheets — interactive tables
Spreadsheets reviewed here are in context of Web-based spreadsheets/interactive tables. The interactive tables enable query, ranking and comparison of these same subject matter across all school districts in Georgia. Use the Web-based interactive tables to view, rank, compare data shown in the above profiles for other districts.
General Demographics
Social Characteristics
Economic Characteristics
Housing Characteristics
One example — click the Economic Characteristics link.  The interactive table appears (wait for table to populate).  On the new page, select Georgia (below table). Next click $MHI button below table. Next click/dblclick the column header E062 to sort in descending order. The following view appears:

Here it can be seen that Fulton has the 6th highest $MHI among all Georgia school districts. Scroll down in the table to see that the Atlanta $MHI is 47th among the Georgia 188 school district areas. Click the ShowAll button to reset or view the start-up view. See additional usage details on the interactive table page.

Recap
Each of these comparative analysis methods has its own advantages and limitations. Ideally they are used in combination. Each of the methods can also be extended. For example, the maps can be structured to show thematic patterns of subject matter in addition to reference maps only. Or show related geographies not depicted in the basic reference map.

Subject Matter
The “weakest link” in effective comparative analysis may be the selection/availability of the subject matter. Are these the right (scope of subject matter) data to examine the issues of interest? … most current data? … trend data required? … accuracy of the data? .. what are the alternatives — and the cost of alternative data?

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