Friday, October 30, 2015

Lab 2

The objective of this lab was to familiarize students with some techniques of data collection and publishing maps in a professional format. I was tasked with downloading Census data for the state of Wisconsin which I then manipulated so it would be compatible with ArcGIS programs. I would then map this data and publish it to an ESRI online service.

Objective 1: Downloading Census Data

For the first objective of this lab I found information from the United States Census Bureau American FactFinder website. The first dataset which I downloaded was the total population of Wisconsin counties. The data set was located by entering parameters within the advanced search function of the website. I ended up with a zip file containing simple spreadsheets with the raw population data. None of the data contained spatial representation. This led me to downloading the Wisconsin counties shapefile from the FactFinder website.

Objective 2: Joining data sets

Once both the data sets which I had downloaded were imported into the ESRI ArcMap program I had to combine them using the “join” feature from ArcMap. I was able to use GEO_ID, an attribute shared by both tables, as the key field for my join. After completing the operation the attribute table of the county shapefile included the population data from the other downloaded file. But when attempting to symbolize the population data I found out that I had to further manipulate the data. The state population was a sting field type (typically used to map nominal data). To map quantities on ArcMap the data type must be set as a quantitative data type. I was able to add an attribute field containing the same information as the original but with a double field. This is much better suited to expressing numbers and ArcMap recognizes that the data can be mapped quantitatively. Below I have included an image of the symbolized population data and the joined attribute table (Figure 1).

Figure 1. Symbolized population data with labeled attribute table types, note the identical numerical data in the original and new fields.

Objective 3: Displaying Housing Data

The third objective for this lab was quite similar to the previous parts of this lab. I downloaded another data set, total Housing in Wisconsin Counties, from the FactFinder website. I joined the information with the Wisconsin shapefile attribute table using the same processes and operations as earlier. The only difference being that I defined the new attribute file data type as long integer instead of double field type. I will concede that this field type requires more memory than double floating but I wanted to see how ArcMap would interact with this slight difference in how a field is defined. I noticed no change in how the data were symbolized.

Objective 4: Build a Layout

My next objective is to make a cartographically sound layout for them. I designed a landscape document with two data frames, each of which displayed a map of Wisconsin. I set the scale of both data frames to 1:4,550,000 and used a Nad 1983 HARN projection designed for Wisconsin (WKID: 3071). I added basic cartographic elements such as scale bars, north arrows, and a legend for both data frames. I choose not to include a base map of any type because I feel that it would overcomplicate a map of this scale where spatial relationships are not pertinent to precise location. I have attached the completed map below (Figure 2).
Figure 2. Completed map of Wisconsin population and housing.

Objective 5: Publishing to ArcGIS Online

For this objective I was tasked to publishing the map document I created to ArcMap online and editing the data display using the services which ESRI offers on their website. After filling out a basic summary for the map I had to remove both table joins to publish the map. Seeing as I had already made new fields and transferred the data to them this was not a problem for the display of data. From this point publishing the data was not a problem.


The final step of this lab was to share my completed webmap to the UWEC Geography and Anthropology organization (One needs to be in this group to see this map). Here is the web link to view the map: http://uwec.maps.arcgis.com/home/webmap/viewer.html?webmap=88b46650ec2b49fa89045e2f402efc8e

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