This first map was the least surprising of the three: it shows the percent change in county population of "some other race"--in other words, people who didn't identify as Black, American Indian, Asian, or Pacific Islander--over the decade from 1990 to 2000. The states that have the highest percent changes are, the border states: California, New Mexico, Arizona, and Texas. The map shows -- unsurprisingly -- that most of our immigration is happening through the US-Mexico border. Maybe if the census had a table for people who identified as Latino/a for this data set, the map would not look the same. I do wonder about that little splotch of color in Washington: do Canadians just really love that county in Washington?
This second map I still have questions about. It shows the Asian Population Density per county in the year 2000. I expected there to be an obvious concentration in California, but what we instead see is areas of high density in California, but also several areas of high density across the South, Mid Atlantic, and North East. Maybe this is the consequence of spending all my time in the Bay Area and Los Angeles county, but I thought there were far fewer Asians in the South than California overall. If you look at the map, though, you'll see that the counties in the eastern US are much smaller than those of California. In order to calculate density, I divided Asian Population of each county by the area of each county, so perhaps county size is what's making the difference in this map.
Finally, this map shows Black Population per county in 2000. The counties with the highest populations seem to be Southern California and the North East, as well as the South and Mid Atlantic. Just like we saw in the map for Asian population density, very few Blacks live in Middle America. I'm not very familiar with the demographics of Southern California, so the high population of San Bernadino County, the large county east of Los Angeles was surprising. We have to remember though that is a map of straight population numbers, and not population density, which could explain San Bernadino--one of the largest counties in the US.
It's amazing that the government provides so much raw data that anyone with mapping software can just play with. Data collection seems like the tricky part; once you have a nicely formatted table, you can do a lot to analyze it relatively easily. As far as the census goes, I was a little disappointed in the some the data they didn't have. "Black, White, Asian, American Indian, and Pacific Islander" is a pretty pathetic set of groupings for the United States population. What about Middle Eastern? What about Latino? Were these not included because they're classifying people by "race" instead of "ethnicity"? These are ambiguous theoretical questions, but they clearly make a difference when you're showing them on a map. I also wonder about break values: having a legend makes the maps above transparent, but the maps could be manipulated to look a totally different way if I changed the break values. The census tutorial hinted that there are standards for US Population values so I used those, but I wonder if many people ignore them to achieve their desired effect.
As always, I'm impressed with my overall GIS experience, but wish the focus of our tutorials was less on fine details ("this is how you change the specific colors) and more on concepts and broad skills ("this is how to calculate values in a table. try doing several of them.") It seems like the exercizes emphasize both about the same, and then I lose the important pieces amongst the fluffy fun stuff. I'd rather my conceptual understanding be solid.
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