Special Topics in GIS (GIS5935): Lab 15

In this week's lab, we learned about the dasymetric mapping. Dasymetric mapping is improving on the results of standard population density in areal weighting by using additional data. We applied this mapping technique to high school zone in Seminole County, FL. We were trying to predicted the number of students between the ages 5 through 14 will be placed in which school zone depending on the location.The imperviousness method seemed to increase the percentage of allocated incorrectly students. This may have to do with the increase area of the school zone not missing the area without the water features.In the areal weighting, the percentage was 44.88%: however, the imperviousness method's percentage was 45.62%.

Special Topics in GIS (GIS5935): Lab 14

In this week's lab, we learned about MAUP. MAUP can affected many different subjects in relation to mapping, such as political boundaries. Gerrymandering is manipulating boundaries of congressional districts to benefits the one's own political gain.

To measure compactness, I looked at the perimeter and length of the districts because the perimeter and length determine the space that the feature occupies in. I had to change the project of the map to projected coordinate system to allow me to utilize the Calculate Geometry feature in the attribute table. I added a new field called Perimeter which measure the area in meter squared. I then added another field called Compactness and open on the Field Calculator. In the Field Calculator, I used the formula (4 * 3.1415 * [Perimeter]) / [Shape_Length]^2*100  allow me to rate the compactness on percentage of compactness.


Congressional District 12 - North Carolina

Special Topics in GIS (GIS5935): Lab 13

The results of the comparison between the two DEMs were very similar yet they were somewhat different from one another. The maximum slope range was higher in SRTM than LIDAR. The possible reason why SRTM has higher value in the maximum slope is the two synthetic aperture radars that were utilized for this scan of the watershed. LIDAR had a higher average slope than SRTM which means that the pulsed laser is able to penetrate the vegetation of the study area and get a better measurement of the slope of the watershed.

To compare the two DEMs I used the slope tool on the SRTM Raster to allow me to note the change in the z-value of the raster image. Once the slope tool was used, the Zonal Statistic tool was used to calculate the average and maximum degrees that both DEMs had. Also, I open up the Data Properties of both DEMs and noted the different cell size of both DEMs.