Wisconsin Census Base Data
GIS I lab 2
Introduction:
The purpose of this lab was to get us familiar with the United States Census data website. We where tasked with the project of downloading and utilizing the copious amount of data at hand and portray said data onto a map of Wisconsin. The overall objective of the lab was to make two maps one including the total population of Wisconsin and the second was to show any other data of our choosing that interested our personal views.
Methods:
The objective of this lab was to utilize and outside source other than ArcGIS to portray data. We where tasked with the objective to familiarize ourselves to joining data with fields and attribute tables in ArcGIS for future use. To accomplish this task there was a few steps that needed to be taking in order to accomplish our goal successfully.
In starting the lab we first needed to download data from the US Census Bureau allowing us to have information about the population within Wisconsin. To do this we needed to open up the US Census data page and locate the information containing Wisconsin. First, we had to narrow our search by selecting specific topics within the US data base, like population, what type of geographical information such as county, then county within a specific state ( in this case Wisconsin). After we then needed to locate the proper attribute table to download, for there is still many types of tables one could choose from. In the case of this lab we wanted to focus on the SF1 data which is the summary data of the census and is the most basic data taken every ten years in the United States. Some of the other options one would see is the ACS which is a more detailed data, that has been put in place since 2005 and has now started to collect every year in high populated cities. However, for the purpose of this lab we needed to have total data and therefor looked at the summary file. Once we had located the appropriate file we then downloaded the file and saved it to our precise folder to extract all of the data.
To extract the data we opened our saved census file and extracted all of the attribute tables, these included metadata tables, the individual data sheets within the excel file, and some other tables that included information about the data. Once extracted the tables then could be connected within ArcGIS. Although at this point the data is not spatially referenced and needs to be linked to a existing file in the mapping program to allow us to manipulate and map the information.
To map the downloaded information of the first map (figure one left map), we downloaded the total population of each individual county we needed to join the census table with the existing ArcGIS map. To accomplish this we opened both the attribute table of the Arcmap and the attribute table of the census data and found what field names where similar to join. In the case of this table it was the Geographical identification number that was similar. Once joined ArcGIS now has the data information in the system and can reference the data.
To display this data however there is one last step we needed to take for the Arc program to understand the data. In the case of this specific census data download Arc could not display the data for it was a string (contained data with both numbers and letters). We first had to make a new field within the attribute table to get narrow down the records in the table. To accomplish this we made a new field named the field, and then used the field calculator to only process the number giving us the values we can use to show in a unique values map. After this step was finished we then could portray the data on Arcmap.
The final objective in this lab was to repeat the previous process but to locate our own interesting data. For my case I wanted to look at the correlation between population numbers and average age within counties. Coming from a small town in the north woods I noticed growing up that the majority of the people seemed to be older in age and retired. I wanted to see if my assumptions held true.
The results where as followed. Once the data was displayed we can see that for many of the counties in the northern region of the state there is significantly low population numbers but the average age is mostly between 47-51 years of age or older. This was a very interesting find for you can also see the areas in which a younger generation if found like in areas of more college based towns. These maps although simplistic could be very useful for business owners, politicians, or other interested parties.
Results:
Sources:
United States Census Bureau (2015, March 16).
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