EDF 5481 READINGS  AND ASSIGNMENTS

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OVERVIEW

As you have already learned, it is expensive and time-consuming to collect data, especially datasets that are sizable or comprehensive. In the early 1970s, the United States Federal government initiated a series of what have come to be called "Social Indicators." The idea was to collect data from different domains (education, health, the status of women and ethnic minorities, public opinion, etc.) and to continue these series over time, thereby tracking change and continuity among Americans. At the same time, other countries, particularly Canada, Western Europe, and Japan, also began indicator series, thus making possible international comparisons. One example is the Third International Mathematics and Science Study (TIMSS). Data were collected in 42 countries in 1995 and in 38 countries in 1999. A recent addition addresses experience with computers and the World Wide Web.

Considerable effort has been devoted to making many of these indicator series compatible over time:

• Questions are asked in the same way
• Changes to questions are established via "split-ballot" testing, i.e., experiments to see whether the revised questions work the same way as the original questions. A good indicator series NEVER shifts question format (or open question codes) arbitrarily.
• Variables are defined in the same way
• Coding categories remain constant
• If coding changes are made, care is taken to make new coding systems compatible with the old, such as the detailed United States Census three digit occupational codes

The number of data archives is already HUGE and it seems to be growing by the minute. Some of the large archives, such as The Roper Center or the Howard W. Odum Institute for Research in Social Science at the University of North Carolina, are simply staggering in the amount of data that they hold.

As you look through some of the pages, you will see that several times I have given the warning: "set aside a day to explore this archive." Do take this warning seriously! One of these archives may hold the answer to your proposed dissertation or provide the basis for a nice conference paper or article. They are definitely worth exploring.

With resources such as these, the novice--and even the experienced--researcher should seriously reconsider whether they really want to gather all of their own data from scratch.

• There is no point in "reinventing the wheel." Why do a small local study when data already exist on regional, national or even international levels? An example is using the "CIRP" to look at college student beliefs, attitudes, and accomplishments instead of convenience samples of your buddy's classes.

• "There is plenty of gold in them thar hills." Most of these databases are so huge that no one investigator could ever analyze everything in them. With each successive year, the possibilities for analysis grow. Further, other researchers may have ideas for analysis that did not occur to the original Principal Investigator. In other words, there is plenty of data for you to do an original analysis--without all the backbreaking work of collecting the data too.

• Many of these archives offer an unprecedented opportunity to track trends over time. How did computer use change from the early 1980s to the late 1990s? What kind of educational preparation do students receive who rise to eminence later on? What are the average student characteristics in research universities as opposed to liberal arts colleges, and how did these characteristics change over time? What are gender differences in Internet use over time?

• YOUR time, resources, and energy. Many researchers, especially junior faculty, have limited resources. With one eye on the tenure clock, junior faculty have limited time too. It takes time, often A LOT of time, to gather your own data. If existing archives have variables that are directly pertinent to your research interests, it is often in your best professional interests to use these archives.

• What is the unit of analysis? Is it an individual? An organization, such as a college or university? A time point for a country or state series? Archives vary and the unit is not always an individual.

• What kinds of variables does the archive cover? Degree attainment? Health practices? Drug or alcohol usage? Attitudes?

• What is the time frame covered by the archive? Examples: the average school FCAT scores for 1998-2001 or The General Social Survey from 1972-2000.

• What is the geographic frame covered by the archive (state? local? United States? international?)

• Who were the sponsor(s)  of the archive (e.g., NSF? NCES? United Faculty of Florida?)

• How did the archive come to be?

• Were the data collected especially for the archive (such as IPEDS)? Or were the data compiled from other sources (such as Web CASPAR)?

• Does the archive contain any tutorials that instruct how to use it (online or otherwise)?

• How are the data available? Are they ready for online analysis? Are the data available to download into your computer? Are the data contained in  .pdf format tables? Are there alternative ways to obtain the data (such as CD-Rom?)? If so, how can the data be obtained?

• Can you simply download the data or must you obtain a CD-Rom or other device from the archive agency?

• How "clean" are the data? One good example is the U.S. government's famous "Falling Through the Net" data (EDF 5400 students will remember this one from Spring 2002) about the "Digital Divide" in Computer and Internet Usage. This is one of the most cited datasets about the Digital Divide and it is appallingly "dirty." The "age" variable contains 3 year olds and 10 year olds and considerable data are missing on racial identification (this was an in-person survey so this variable should have been mostly complete). Apparently, the government was in such a rush to put up the dataset, the data contain a LOT of careless errors. As a result, I consider any estimates from these data to be VERY unreliable.

• Is there a charge for the data? If so, what is the cost? Most archival costs are surprisingly reasonable, when you consider the effort involved in the first place. For example, the cost of the ENTIRE General Social Survey archive, from 1972 to 2000, over 40,000 interviews, in SPSS ready format, and including a hard copy of the Codebook is less than $300. Compare this with the millions of dollars it cost to gather the data. Don't forget: you will incur time and financial costs to gather and process your own data. It may, indeed, turn out to be cheaper to use the archive.

• What kinds of analyses can be done online? Frequency distributions? Cross-tabulations? Multiple regression or other multivariate analyses? See if the archive uses the California-Berkeley Survey Documentation and Analysis (SDA) program which is simple to use, covers most basic statistics, and is unbelievably fast (including on a dial-up system like my home computer). Many online datasets are now directly linked to the SDA system. (Gossip has it that SPSS wants to develop and distribute a competing online analysis system--but you can bet that SPSS will charge to use it! The SDA system is FREE!)

• Is a questionnaire available or some other original document describing each variable in detail? Maybe it is available as a separate link or as a .pdf document (did you remember to download the Adobe Acrobat Reader?)

• What is mentioned about coverage or response rate? For example, data are missing from several states in early data series about abortion. Some surveys have completed interviews with less than half of the originally contacted respondents. In other cases, such as the CIRP, response rates can vary considerably from college to college.

• Do you need any kind of license from the data agency? Many data sets at the National Science Foundation, the National Center for Educational Statistics, and other agencies require you to have a license if you work with what is called the "unit record" data. Unit record data is the "raw data" where each record is an individual or an institution. This means the person or institution could plausibly be identified. Obtaining a license is typically not a problem for legitimate researchers but it does necessitate some paperwork so be prepared to check about this and budget some time accordingly.

• What was the mode of data collection? In-person surveys may give different results than telephone surveys. The top administrator of a university may access different data than a rank-and-file faculty member.

• How recently has the database been monitored or updated? See if you can find a date on the page, typically at the very top or the very bottom of the page. "Old pages" may have missing links, unfixed errors, omit the most recent updates to files, or simply may not work.

November 19 2002
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Susan Carol Losh

Always under construction as new databases are entered.
 

EDF 5481 READINGS AND ASSIGNMENTS

OVERVIEW