Centers Galore

Alright, I think I finally figured out why I was having trouble earlier with the data set. When I joined the data, I joined it under the wrong column id. After matching them correctly, I believe I solved the problem that I was having.

So, what you see here is the housing center in the Urban Area of Omaha. Notice the Urban Area contains parts of Douglas and Sarpy County. The unit of measure was Census Blocks. Also, I wanted to test the mean center, and weighed the center to African Americans, Hispanics, and Whites. As you can see here, I am getting a much better picture and assessment of the population and housing centers of the UA of Omaha.

The bottom link contains a zip file with shp files, jpegs, eps, dbfs, and mxds of the above map.

http://myweb.unomaha.edu/~jpence/Centers.zip

You can download the data if you want to take a look at it.

Also, feel free to critique the map quality. One of the things I would like to get out of this class is to create more professional, quality maps. I hope we spend time more time in class going over map quality, and what can be done to improve it.

Until Then,

Enjoy

Updated Info About Centers

Hello All. I just wanted to post and tell you what I have found after playing around with ArcMap for a while.

First off, what you see in the above picture is the Geometric Center of the United States. I do not remember who said it in class, but you do have to dissolve the state boundaries in order to get an accurate depiction of the geometric center. This is easy enough to do, just make sure when you use the dissolve function you do not weight it by anything.

Also, one of the errors that was often seen today, when performing the mean center function, was the data used was not projected. One way to fix this is after you perform the mean center function, you then need to project the point that was created. This will correct the problem if you are receiving a message that the data you are using is not projected.

In addition, I wanted to post the vector format of this map on this blog for download. That way, this map could possibly be used for the activity next week. You can not directly post pictures in vector format in this blog. So what I did was include a link to my web page from UNO. The following link is a downloadable EPS file of this map:

http://myweb.unomaha.edu/~jpence/US%20Geom%20Center.eps

The file should just be ready to download as normal. I also tried to link it with SVG, but this did not work. I assume if I uploaded this with PDF or AI file vector file formats, they would automatically download. In the future, I will zip these files and they should be ready to download.

I will try to get a correct household center map out tomorrow, with the right files.

Until then

Jobs Center... Hopefully

Alright, I hope this is right. Housing Data and population data is easy to come by, all you have to do is get the information from the US Census. Well, in part of my thesis, one of the aspects I have to look at is job distribution. For example, if Job density is relatively high, Urban Sprawl is low. And if Job Density is low and sprawled out, then Urban Sprawl has the potential to be high. The problem is where can you find job data.

Well, under the methodology I have chosen for my thesis (Galster et al.) they utilized the Census Transportation Planning Package. It gives a lot of information based on commuting times, income related to commuting times, and all sorts of things. My problem is, where is the Occupation data that is supposed to come with the CTPP package?

Well, I think I have found it and accurately calculated the Job Center in Douglas County. Jobs are aggregated to the Traffic Analysis Zone level. This should cover every type of occupation, not just a certain few.

Also, the color gradient shows the overall job distribution of Douglas County. There are anywhere from 4-8000 jobs per TAZ.

So hopefully, this is correct.

Household Center, the UA of Omaha

The last post shows what the household center is for Douglas County. I have since then calculated the Urban Area of Omaha's Household Center by Census Block. As you can see from the previous, it shifts farther East, but otherwise that is about it.

Household Center

This is my first attempt doing the mean center exercise for this week. What you are seeing is Douglas County, and the boundary is Census Block for the year 2000. Housing units are aggregated to Census Block, and the Weighted Mean Center was calculated using ArcMap's Mean Center function. Housing units is the weight used.

Look for more to come. Job distribution may take awhile, as I am having trouble with the data

1st Post

This is my Test of my first Blogg

Enjoy