ACS Profile Reports: Usage Notes Rev. 7/22/2009

Quick Links ACS Profile Reports ACS Trends Reports SF3 Profiles (2000) Circular Area Profiles SF3 Trend Reports Detailed SF3 Profiles IRS Migration Profile Missouri County Data Map Applinks Master Menu MABLE/Geocorr 2K RxA Cure for the Common Codes American FactFinder Return to acsprofile web application. Overview These reports represent the Missouri Census Data Center's attempt to distill the most frequently accessed data items from the Census Bureau's American Community Survey summary data products. American FactFinder web site users will be familiar with the ACS-based Data Profile reports on that site. These reports obviously are modeled after those Bureau products. (The source of most of the data used in these reports come from the xls files with Data Profiles data distributed by the Census Bureau.) But these profiles do differ in significant ways, in terms of both form and content. Some key differences: The MCDC profiles allow the user to select up to 4 geographic areas and will display the data for those areas side by side to facilitate comparison. These profiles will always provide both a count and a percentage measure whenever possible. So (for example) while the Bureau profile shows only poverty rates, our profile displays both counts and percentages of poor persons (or families, etc.) Statistical reliability of the data are displayed here using a 3-tiered font weighting scheme with MOE-based values (relative MOE's and confidence intervals for counts; MOE values for Percents) accessible by holding the mouse over any data item on the report for 1 second. (See details, below). The data used in these reports are stored in datasets that can be accessed and downloaded (using our Dexter web extraction module). You can easily access these data for every geographic area in the country in a single query. Profiles on the Bureau web site only provide access to the data 1 geographic area at a time. Header Lines These reports contain two header lines. The first is constant - "ACS Profile Reports 20<yy>"; the second identifies the (primary - i.e. first chosen) geographic area being summarized. It begins with the name of the area (if applicable) and then the standard geographic code for the area. This is the geoid code used by the Census Bureau (although not always visible to the user) in their AFF databases. It is comprised of a 3-digit geography type code (040 for a state, 050 for a county, 160 for a city, etc) followed by a 2-digit geographic component code (usually "00" to indicate "not a geographic component"). The letters "US" separate the first 2 codes from the FIPS code(s) that follow. The geoid code for the city of Columbia, MO is 16000US2915670 . The 7 digits following "US" include the FIPS state code (29) and the FIPS place code (15670). General Layout of Tables The report is really a series of up to 4 broad-subject-category profiles: Demographic, Economic, Social and Housing. The user can opt to display any subset of these 4 profiles. Those chosen will appear in the stated order (with Demographic first and Housing last on the page). Each profile is preceded by a bold header line identifying it. There is a menu bar across the top that allows you to go directly to any of the sub-profiles. The reports are broken into a Subject column, one to four Number-Percent column groups with the name of the area being summarized displayed in the over-arching first header row. The order of the geographic areas left to right across the page is determined by the order in which you select them (or in which they were selected for you if you came in directly from a web link). A final column at the far right of the report labeled "Base Table(s)". In some rows you will see the name of a base table used as a hyperlink. The table referenced contains more detailed data related to the current data item (and in some cases is the source of that data item). A click on one of these base table hyperlinks invokes an application (called acstabgen) that will display that table for each of the geographic areas currently selected. This amounts then to a kind of demographic "drill down" for more detailed information. The lines of the table consist of Table Header lines identifying the subject matter and "universe" (i.e. the kind of entities being counted or measured). These are highlighted with a gray background. The first table header line is a hyperlink to the metadata where you can get more detailed information about the variables in that table. The detail lines of the table are divided into columns. The Subject column identifies the data displayed on the line. Indentation is used to indicate subordinate data. For example, in Table 24, "Owner Occupied Units" is indented within "Occupied Housing Units". Typically, the first detail line in a table contains the total universe count and is displayed in bold. All items that count or measure the entire table universe are left justified and bolded. The Number columns contain a count or other measure (mean, median or occasionally a percentage). The Percent columns are filled in if and only if the item is a count. It is usually (but not always) a percentage of the next higher level count. (To see for sure what denominator was used to calculate the percentage follow the table-header link to the metadata and locate the row for the current data item; the "Universe" column contains the name of the variable used as the denominator.) Showing Statistical Reliability of Numbers (MOEs) These reports use two methods for helping users understand the statistical reliability of the numbers. The first involves using heavier or lighter fonts to display values which are deemed as notably reliable or unreliable. The datasets used in generating the reports include a margin-of-error (MOE) item for each variable provided by the Census Bureau. We use these MOE values to calculate a relative MOE value, defined as the MOE as a percent of the numeric estimate. For example, for the state of Missouri for 2006 the variable MedianRent had a value of 607 with a corresponding MOE value of 6. This yields a RMOE (relative MOE) value of 1% (6 as a percent of 607). Obviously, a pretty reliable number. Whenever we display a value we use a bold font if the RMOE for that item is less than 15%; if it is 35% or greater we display the value in a light gray to make it somewhat hard to read. Finally, when the RMOE is in the 15-34.9% interval we display it with a normal weight font in black. (The corresponding Percent column value is displayed with the same font/color as the Number value.) If the user moves the cursor over a data item in the report and leaves it there for 1 second a pop-up box will appear to display reliability information in the form of the RMOE and the confidence interval (if this does not work make sure your browser window has focus by clicking within the window and then trying again). The bounds of the confidence interval are derived by simply subtracting and adding the MOE value to the estimate (and, in most case, making sure the lower bound does not go below 0). Similarly, if the cursor is placed over a Percent column item for 1 second a pop-up box will display the MOE for the value, expressed in percentage points. For example, if a Percent value is 12.5 and the pop-up box displays "+/- 0.9" it means that the 90% confidence interval for this item is 11.6 to 13.4. Charts You will see this chart icon in the upper right corner of most of the tables. Click on these icon links to display charts associated with the tables. They will be dynamically generated and will pop up in a new window. You need to have the Adobe Flash Player application installed on your PC in order to view the charts. We suggest closing these windows before going back to display more, since they will be displayed in the same window and it may not pop up if it is already open. (The chart may be displayed but in a window that is not automatically made visible - you could still view it by clicking on its entry in the task bar.) Indentation in the Subject Column Indentation is used to indicate qualifying of categories. For example in Table 4 the 4th line is labeled "White alone" and is indented within the previous "Not Hispanic or Latino" line. Thus this item is the count of persons who are not only white alone but are also not Hispanic. The following 4 items in this table are at the same indentation level, indicating that they are counts of categories that include being non Hispanic. Downloading the Data At the bottom of the report you will see a row of hyerlinks to related pages. The third link is "Extract Data via Dexter". This refers to the MCDC's Dexter web application for accessing our data collection. This hyperlink bypasses the usual explore-the-directory phase of accessing a dataset, and takes you directly to the dexter (data extraction utility application) first screen with the appropriate dataset already selected. The page includes a link to the Dexter Quick Start Guide, appropriate for first-time users, as well as to more detailed online help for using the application. You may need to specify a filter to avoid getting data for the entire dataset (this would typically involve coding a filter based on SumLev and/or State variables.) Dexter also allows you to select variables, so you do not have to take the entire 950 variables (more or less -- it varies slightly with geographic level). Using this tool it would be very easy (for example) to generate a csv file containing just the geoid, Areaname and MedHHIncome variables for all available cities (or counties, or PUMAs, or Congressional Districts) in the entire US (or for one or more selected states.) Using the Front End Menu There are a number of ways that users can come to this application, but one of the most common is to get here by accessing the front end menu page for the application (this is where you go if you choose the ACS Profile Reports option form the Quick Links menu box on most MCDC web pages, for example.) We have tried to make this page simple and intuitive but it never hurts to tell people what we hope will be somewhat obvious. The application will display profiles for up to 4 geographic areas for a single ACS data year. When the application first appears there is a select list that lets you choose from the available years of data. You can only make this choice once (it defaults to the latest available year, so if that's what you want you do not have to do anything). After you select the Year value it cannot be changed and the drop-down select list will not even be displayed on subsequent screens. If you need to change the Year selection you can use the Reset button near the bottom of the screen. Doing so will be like starting over and any selections you have made will be lost. The Step 0: section at the top of the page allows you to limit your geographic search to a single state, or to choose the All States option if you do not want to add this restriction. The choice you make here will effect what geographic areas appear on the select menus that you will be using in the Step 1 section of the page. Remember that you can make up to 4 geographic selections. If you want to select geographies from different states you can always specify a state in Step 0 and choose a county from that state, then go back and change the state selection from Step 0 and choose a second county from the newly-selected state. If you choose "All States" in Step 0 and then click on Counties in Step 1 you will get a select list of all 3000+ counties in the entire country. Important note: After choosing a state off the select list you must click the Select State button before that selection becomes effective. Similarly, in Step 1 you have to both choose an Area Type off the menu and then click the Select Area Type button in order to complete that step and make the selection effective. The drop-down select menu that appears for Step 2 is the only one that allows multiple selections (by holding down the control key while clicking on your 2nd and subsequent choices). Of course, remember that the selection limit is 4 overall. Selecting more than 4 areas may cause the application to fail. The order in which you make your AreaType-Area selections is the left-to-right order in which the data for these areas will be displayed in the report. Related Applications For most geographic levels there will also be a hyperlink at the bottom of the report labeled "Related Applications". This link will take you to the "applinks" web utility which will allow you to choose from a menu of other reports/applications available for the current (first chosen) geographic area. For example, you will be able to link to the corresponding "dp3_2k" report (SF3-based profile) and a comparable report based on 1990 census data (for many, but not all geographic areas nationwide). A few of these applications will only be available for Missouri or other limited universes. Return to acsprofile web application.

This file last modified Wednesday July 22, 2009, 11:11:10