Understanding Geography Layers:
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| In the Missional Culturescape, data, spatial geography, and mapping are all tied together to create a visualization of geographic information. In order to better understand this geographical representation one must understand four basic areas that this article will review: 1) divisions of spatial geography; 2) nesting data and geographical representation; and 3) overlapping data and geographical representation, 4) interpreting spatial representation for missional purposes. |
Divisions of Spatial Geography |
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One core issue of spatial geography often determines the usability of
the geographic representation for missional purposes -- the way in which
the data and its representation are divided. Establishing the
geographic boundaries and how it relates to the underlying data becomes
crucial in both understanding the visual representation and applying it
to missional issues. |
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you "slice" your community has great significance for developing a
missional strategy. |
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Nesting Data & Geographical Representation |
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 Some geographic layers are like nesting tables, they fit within each other. |
We are all familiar with "nesting tables" -- some of us have a set in
our homes or offices. Geographical data and map representation of
boundaries established by the US Census Bureau are based on this nesting
idea. While there are exceptions of course, most geographical
areas of the United States follow this pattern. In general, states may be divided into counties or parishes. However, at times these counties may be aggregated to create administrative regions within the state. DMAs are used by Arbitron to measure Media outlets in various regional areas. These Direct Media Areas represent regional areas (sometimes across state lines) that are usually created by aggregating several counties together. Counties are divided into Census Tracts. In turn these Census Tracts are actually the aggregation of several Block Groups within the Census Tracts. Block Groups represent several Census Blocks that are combined to form the Block Group. Data is created by adding all of the geographic layers from a lower layer of geography to produce totals at the higher layer of geography. For example, all of the Block Groups in a state could be added together to produce state totals. Or, one could add the Block Groups within a Census Tract to produce tract totals. In this way the data is scalable. Data Mapping may be created by mapping the differences of the lower layer that makes up the higher layer. For example, if we assigned a value on a scale of 1 to 5 to each of the block groups in a county, we could map these values and show the variances -- at the block group layer -- on that value for the county. Benefit comes from seeing the differences at a lower layer of geography. |
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Overlapping Data & Geographical Representation |
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 Some geographic layers overlap other layers of geography like the triangular nesting tables above. |
The picture on the left shows three
triangular nesting tables that have turned in such a way as to produce
overlapping tables. While the height of the tables varies which
allows them to fit within each other, they also partially overlap one
another. The overlapping nature of data and its geographical representation results from additional sets of boundaries that are not nested completely within another geographical layer. Three types of overlapping boundaries have developed -- each of which poses their own unique difficulties. 1. Many different government agencies have established specific boundaries to meet their own needs -- without regard to other existing boundaries. For example, Zip Codes were created by the US Postal Service to make it easier for them to sort and deliver the mail. However, zip codes do not "nest" under any other geographic layer -- they overlap other areas. The diagram on the right was produced by the US Census Bureau. If you cannot read it, you may want to click on it, opening it within another window or tab to see a larger version. Here are other boundaries that do not "fit: under the nesting categories discussed earlier in this article: -- Zip Codes and Zip Code tabulation areas -- School Districts, Congressional Districts, and Economic Places -- Voting Districts & State Legislative Districts -- Traffic Analysis Zones -- Country Subdivisions -- Subbarios -- Census Places (cities and towns) -- MSAs (Metropolitan Statistical Areas) 2. Radius areas are circular distances from a beginning point (typically 5 mile or a 10 km circumference around the starting point). 3. Polygon areas are types of overlapping boundaries. A polygon overlaps established geographical boundaries and thus require statistical modeling and algorithms to deal with calculating data that overlaps geographically. Future plans for the Missional Culturescape include developing the mapping and reporting capability need to deliver radius and polygon maps and reports that accurately represents data while taking into account the overlapping nature of this type of representation. |
 Geographical Hierarchy chart created by the US Census Bureau click for larger view |
Interpreting Spatial Representation for Missional PurposesDefining the Value that is Represented
The Missional Culturescape has about 800 pieces of information (variables) that can be used to create maps at various layers of geography. Each of the variables in the Missional Culturescape may be mapped across your community culturescape to gain a better understanding of your sociocultural setting. You will be able to use these variables to create specific thematic maps that you may use to share this information with others. To explore these variables, click on the links for: Socioscape Demoscape Ethnoscape Hispanicscape Evangelscape Linkscape Needscape Motivescape Specialscape.
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| Discerning the Differences Between Represented Values | ||
| Determining Missional Application | ||
| Deciding Your Next Steps | ||
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