GUS 0265: Applications in GIS
Spring 2007
Lab 3: Vector and Raster Analysis
The purpose of this lab is to review basic vector and raster data handling and operations, as well as
introduce raster point distance and density functions.
Objectives
This lab concerns environmental justice in New Jersey. Your objective for this lab is to analyze the
spatial pattern of air pollution facilities with regards to the distribution of socioeconomic character and
land use.
Your analysis should address the following general research questions:
1. Is there a spatial relationship between the distribution of facilities and percent minority (defined
here as either non-white or Hispanic [Hispanics can be of any race], population density, median
owner-occupied housing value, and commercial/industrial/transportation land use?
2. If a spatial relationship does exist between the location of facilities and any of these variables,
what is the form of that relationship?
Data
The data for this project can be found in the directory S:/GUS_0265/lab_03
facilities
a shapefile of facilities in New Jersey that release air pollution and are listed in the
Environmental Protections Agency’s Aerometric Information Retrieval System (AIRS).
The ‘Afsid’ field is the unique identifier for each facility.
tracts
a shapefile of Census 2000 tract boundaries for New Jersey. The field ‘Areakey’ is the
unique identifier for each tract.
tracts_data
a .dbf file with a few select Census 2000 data fields. The field ‘Areakey’ is the unique
identifier for each tract. The field ‘Arealand’ is the land area of each tract in square
meters.
Sf3
A .pdf file that is the data dictionary for Census 2000 Summary File 3 data, including the
data contained within tracts_data.dbf. You can use this file to find out the meaning of the
field names in the tracts_data.dbf file.
nlcd_nj
a raster grid of land cover for New Jersey
new_jersey_readme.txt
information on the New Jersey land cover data
new_jeresey_FGDC.txt
metadata for the New Jersey land cover data
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Deliverables
Perform the following specific analyses:
1. Spatial Coincidence. Classify the tracts into two groups: those that contain facilities and those
that do not. For each tract group, calculate the percent minority, population density, and percent
commercial/industrial/transportation land use. Report the summarized socioeconomic and land
cover variables for each tract group in a table.
2. Distance to Nearest Facility. Use a raster spread (Euclidean distance) function to derive a grid of
distance to the nearest facility. For each tract calculate the mean distance for all grid cells within
the tract. Classify the tracts into five exclusive groups based on a quantile classification scheme
of mean distance to the nearest facility (i.e. each group will contain 20% of the tracts). For each
tract group, calculate the percent minority, population density, and percent
commercial/industrial/transportation land use. Create charts (column charts work well)
expressing the values of the summarized socioeconomic and land cover variables for each tract
group. You can use Excel to create the charts.
3. Density of Facilities: Repeat the above step 2, except instead of focusing on the distance to the
nearest facility, use a raster point density function to derive a grid of facility density, and for each
tract calculate the mean density. For the density function, use a radius distance of 100 meters. As
in step 2, report your results using charts.
You should turn in a 2-3 page report in the style detailed on the Lab Information web page
(http://astro.temple.edu/~jmennis/Courses/GUS_0265/lab.htm). Remember, the report must include the
following sections:


Introduction:
Methods:


Results:
Conclusion:
the purpose of the report; a statement of the problem.
a brief description of the data and the methods (operations) you used to do the
analysis.
a summary of the results
an interpretation of the results, an assessment of accuracy and sources of error in
the analysis, as well as recommendation for further actions.
Note that the results section must include the table of the Spatial Coincidence analysis results, and charts
for the Distance to Nearest Facility and Density of Facilities analyses.
Supplement your report with maps and diagrams reporting on the data and methods. Each table and
figure should be on a separate page, labeled as table or figure 1, 2, 3, and so on, and referenced in the text
appropriately. The tables and figures should reside at the end of the report in the order in which they are
referenced in the text.
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