Census Data Lookup


The assignment is to use the U.S. Census Bureau's web-site to look-up data to allow you to compare two neighborhoods to each other and to both Honolulu County as a whole and to the Urban Honolulu CDP (Census Designated Place).

You should compare the geographic units on the basis of four different census data tables: 2010 100% Population Count plus three others of your choosing.


US Census Bureau website , especially the Data -> American FactFinder tab.

Census Tract and Block Reference Maps on the page under the tab... Geography -> 2010 Census Geographic Products

Update to reflect move to ACS

The Census Bureau has stopped using the "Long Form" as of the 2010 census. Instead of the previous decenial collection of demographic, economic, and housing data, from 1/6 of households, similar data are, since 2005, collected monthly in the American Community Survy (ACS). Part of this change has been the development of a new set of tools to access this new data. Read about this on the US Census Bureau website (www.census.gov/acs/www) and especially the http://www.census.gov/acs/www/about_the_survey/american_community_survey/> American Community Survey page, and the links from it.

Editiorializing a little: I am not yet possessed of a thoroughly informed opinon as to the value of the changes at Census. The website offers more tools, but accessing data seems more complex. Comparability with the past is more difficult. Inclusion of columns of normalized (%) data make some comparisons easier.

The Census replaced a 1-in-6 decenial long-form survey with an annual 1-in-40 survey (the ACS). That is supposed to mean that the census will have a more even workload and will provide more current data, released as moving window 1-, 3-, and 5-year summaries. The different reporting periods are related to the populations of the geographic reporting units. Areas with 65,000 or more people are reported at 1-yr granualrity; with populations greater than 20,000 at 3-yr granularity, and with smaller populations (down to 100 people) at the 5-yr resolution. The five-year data would then equate approximately to a 1-in-8 sample (not quite as large a sample as the old 1-in-6 long-form), that is more current about half the time, though it is not an instantaneous temporal freeze-frame so much as a slow-shutter blurred snapshot).

Most frustrating for this exercise is that access to blockgroup level 5-year ACS data in 2012 seems unavailable through the American Factfinder 2 tool --- tract level seems to be the finest. We used to be able to do this exercise at the blockgroup level, and I hope that we will again but for now (2012) it seems that we'll have to make due with the tract level. I see this as a sigfnificant step backward for studying the city through census data.

Tools Overview

The basic issue is selecting the data that you want from the huge amount that the census provides.

The new website (here) presents multiple access tools, including down the left side of the screen:

It also has hierarchical tabs across the top of the main page:
People | Business | Geography | Data | Research | Newsroom
as well as more than seventy links at the bottom of the page, some of which lead to useful data selection tools.

NB: The Data -> American Factfinder Tab is where you will find the most useful level of control for this exercise.


  1. Access the Census Bureau web-site to read about the US Census and the products it produces. In particular, be sure you understand the hierarcy of census geography and the kinds of data that should be in the decenial census and the ACS.
  2. Identify two neighborhoods that you want to compare to each other, to the Urban Honolulu CDP, and to the County.
  3. Use the Census Tract map shortcut here to locate Tracts within Urban Honolulu to compare. Note the Tract numbers, e.g. "48" or "27.01".
  4. On the American FactFinder page, (Data -> American FactFinder) use the menu boxes on the left of the panel to build the query to select the data tables you want for your comparisons.

The Write-up

Your write-up should be a one page comparison stapled on top of your tables and maps. It should identify the two neighborhoods that you considered, the Census Tracts within each neighborhood, and the variables that you are using for the comparison. Attach your tables to the report just to keep things together.

The comparison should employ comparable units. Usually, this involves converting "count data" to ratios, proportions, or percentages, i.e., comparing the percentages of households headed by a single parent for two areas is often more useful than comparing the numbers of such households, and comparing population densities (population/area) or even population/(husing units) is usually more interesting than just comparing absolute populations.

Addendum: You might like to think of this as a classic (if formulaic) comparative essay, in which you introduce the topic ("This is a comparison of two Oahu neighborhoods, Palolo and Waikiki, using year 2010 US Census and ACS data..."), perhaps indicating what you expect(ed) to find ("It was expected that Palolo and Waikiki are quite different in pupulation density, and in household income but similar in travel times to work. Further it was expected that Palolo would be more like Oahu as a whole."). Follow it with a sentence or two indicating what data you will use, and how you use it, to support/reject the thesis come(s) next. ("Data from the 2010 US Census, tables for 100% Population (table #?), Median Household Income table #?), and Rent (Table #?), will be used to make the comparison.") Then you make your specific comparisons ("...the median household income in Palolo is $X and that in Waikiki is $Y, which is closer to Oahu's $Z..."). Use appropriate statistical comparison techniques that you know about (chi square, anyone?). Finally, end with a concluding sentence summing up what you found ("In conclusion, it seems that Waikiki and Palolo are a lot alike [or really different?], on these measures, and that both are different from [much like] Oahu's 'average'"). Easy as pie!

As usual, put your name, the assignment name "Census Data Lookup" and the date in the upper right corner of the front page. Thanks.