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Lab 3: Thematic Mapping and Data presentation
This lab frequently refers to the folders UrbanGIS\MyData. Save your work on
M:\\students\onyen\lab3 ; data are found at M:\\data\lab3 . Some pages of this lab are
skipped on purpose. Do not be concerned that pdf page numbers do not include all pages.
The assignment will be submitted as a .doc file in your folder. Paste in the printscreens,
cropping as necessary.
This is a long lab that is equal in weight to two laboratory assignments. Plan accordingly.
Part I.
1. Print screen of map from extra challenge on p. 469.
2. What is the dimensionality of each of the data layers?
The census layer is represented by dots. The waterbodies and landmarks data layers are polygons. The shorelines data layer is made up of lines. Census tracts = polygons; landmarks can also be points -.25
3. Print screen of resulting bx_demog layer resulting at end of task 4, p. 480. Justify
the number of classes that you use and the breaks in the data.
I used 10 classes within the data because it gave a more accurate depiction of how the levels of minority populations vary within small areas as opposed to 5 classes. The fewer number of classes did not highlight more detailed population differences and gave only a general overview of the minority population difference. I decided on the naturally occurring breaks combined with what I thought most accurately represented the minority populations in the Bronx region.
4. What measurement levels of data are mapped?
The minority percentage data mapped is ratio data.
5. What are the two types of thematic maps covered in these exercises? What
questions are they best to describe?
The two types of thematic maps covered in these exercises are dot maps and choropleth maps. The dot map is best used to describe data that shows a distribution such as a population against a base map. The choropleth map is the shaded map that uses data that is classes and areas are shaded more or less densely according to their value.
-.5 dot density: variation in spatial density
Choropleth: rates, percentages, and ratios
1. Part II.
1. Create informative layout of the data that you have worked with over the past 2
weeks. Include legends, titles, north arrow, scale, text, and bar chart. Text should
describe 1) name, section, and date , 2) data sources, and 3) describe the maps that are
displayed. Include dot density and chorpleth maps. Bar chart should be properly
labeled with title, legend, and use one option from your choices. The final layout will
be judged according to visual structure of the layout as described in lab.
-1 need scale/arrow for each Maps look great!