19/20
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 data is made up of points with are represented by the dots and area which is the different census blocks. Census tracts are polygons The shoreline is an example of a line (but could also be defined as a polygon). Both water bodies and land marks are represented in polygons because they have a defined area. Landmarks can also be points depending on the scale
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 five classes in the defined interval classification. I did this because five clearly represented the spread or range of percentages in the data. More than five creates too many divides and makes the map too complicated. At the same time less than five classes over –simplified the data and group too many categories together. The break values went up in percentages by 20. The first being 0%-20%, second 21%-40%, third 41%-60%, fourth 61%-80%, and fifth 81%-100%.
4. What measurement levels of data are mapped?
The level of measurement used is ratio. Ratio is on an absolute scale where zero means something. This is important because the data represented is a population density percentage which cannot have a negative number and where zero means something.
5. What are the two types of thematic maps covered in these exercises? What
questions are they best to describe?
The two types of maps are Cloropleth and Dot density. For dot density, the density of dots illustrates the intensity of the phenomenon and works best with absolute numbers. It describes frequency only. Cloropleth on the other hand, show rates, percentages or ratios. It is aggregated by unit of analysis and should not be used for absolute numbers.
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.
Map a little cluttered at top with text -1