Tuesday, January 25, 2011

Lab 3 - Geocoding!

Map of public schools in Alameda County, Ca.
(with special zoom in of my highschool, Berkeley High)



The enrollment data shows that there were 33 schools that had enrollment numbers less than 1366 children. there were 21 schools in the middle class of >1366 and <2733. And finally only three schools had enrollments larger than 2733.


For this lab assignment, I decided to stick close to home, and focus on schools in the county I grew up in - Alameda County. I went to a huge high school in Berkeley, so I feel that school enrollment size is a very important issue. I have experienced first hand what over sized classes and under-funding can do, so I decided to geocode a database of all the (public) high schools in Alameda county, and label them according to how big they are enrollment-wise. I split the schools into groups using the equal interval classification, and as you can see, the vast majority of them ended up being in the smallest group, the <1366 kids group. In the biggest group, >2733, there are only three schools!

Geocoding was a great tool to use to locate and analyze school data. I can easily see where all the schools are and the concentration of schools within the different cities in Alameda county. That in and of itself is extremely useful, but the potential is pretty much unlimited in terms of all the analysis you can perform on the data. I decided to look at enrollment information, but I could have performed a buffer analysis to see how close schools are to various types of buildings/parks/highways. Or I could have done a buffer to show where sex offenders would have to live to avoid violating the school buffer law.

Pretty much the only draw back of georeferencing is having to compile a database of all the information you need. I probably spent two or so hours getting addresses and enrollment data, and I was only doing it for highschools. It would have taken forever if I had included elementary/middle schools or private schools!

Just for fun, I included a close up of the street grid immediately around my old high school, Berkeley High. I included an extent grid so that you can tell where it is in relation to the county at large. Incidentally, the most interesting result of this project for me was that I was fully justified in thinking that my high school was huge! It turns out that Berkeley High is the second biggest high school in Alameda county, at around 3,350 students. The biggest high school is in Union City, and has over 4,000 students!