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Cornell's Roper Center Membership

What is the Roper Center?

Located here at Cornell, the Roper Center for Public Opinion Research maintains a large data archive of public opinion surveys. It houses data from well-known organizations (such as Gallup, Yankelovich, network news organizations, and USIA). It also has substantial holdings of historical American surveys and polls conducted abroad by foreign firms.

The Roper Center promotes research in survey methodology, survey construction and administration, and the responsible use of polling results. Cornell has been a member of the Roper Center since 1997 and now houses the Center, known as Roper@Cornell.

What services are available to me?

Cornellians can take advantage of two benefits: obtaining exclusive Roper datasets and access to the iPOLL question bank.

Roper distributes thousands of datasets for use in secondary analysis. Roper online catalog entries have general information: topics covered, number of questions, number of variables, sample size and composition. Most--but not all--polls in the catalog have machine-readable codebooks, which can be freely downloaded.

About 75% of U.S. poll datasets from Roper can be downloaded via Roper Express. Current Cornell faculty, staff, and students are eligible to use this service, which requires that you

Datasets eligible for Roper Express are tagged with the icon within catalog entries. Data Archive staff can order other U.S. datasets and foreign studies for you.

Roper's iPOLL database has almost 500,000 questions derived from American opinion surveys. It also includes questions from surveys not archived as datasets by the Roper Center. Questions are usually accompanied by response frequencies. You do not have to create an acccount to use iPOLL.

Roper provides very thorough guides to RoperExplorer and iPOLL on its site. The data librarian at Rutgers University has compiled a short introduction to Roper Express and iPOLL as part of his Data Snapshots series on YouTube.

Can I use the iPOLL database from off campus?

Yes, by using this link. It will authenticate you as a Cornell user.

How do I use Roper datasets?

The datasets themselves are usually in plain text format or SPSS datasets (.sav or .por files). SPSS datasets can (obviously) be used with SPSS statistical software or converted to other formats (Excel, SAS, Mintab, and so forth) using StatTransfer.

Preparing plain text (ASCII) files for analysis isn't difficult, but it is time consuming. One alternative is an input wizard, which is available in SPSS. This feature requires few programming skills, although it works best if the dataset doesn't have too many variables.

Using Roper datasets can be challenging, especially when using older polls and surveys not conducted in English. However, using the actual microdata files gives you the flexibility to examine poll results in a way not possible with preformatted tables.

Are there any restrictions on use of the files?

Cornell users can't redistribute the data they obtain via our membership to non-Cornellians without permission from the Roper Center. As with all sources, you should appropriately cite Roper archive material, including the original survey and the fact that the data were acquired from the Roper Center for Public Opinion Research. The Center's Responsible Use Statement has a complete description of use restrictions and suggestions on how to cite datasets.

The Roper Center distributes only public-use microdata, making it highly unlikely that individual respondents in surveys can be identified. However, the Cornell Institutional Review Board for Human Participants does not include Roper on its list of dataset distributors of data excluded from review. Also, you must obtain HCHS approval to merge the microdata with any other data that could increase the possibility of disclosure. The IRB provides an informative document that discusses this and other topics related to data use, Secondary Data Analysis Requiring Review.

Need more information?

The Roper site has a helpful FAQ page. The data librarian at Rutgers University has a short introduction to Roper Express and iPOLL as part of his Data Snapshots series on YouTube.