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Roper Center to Archive Non-Probability Polls, Other Methods

May 02, 2019

New acquisitions policy part of larger effort to increase transparency in polling research


Ithaca, NY (May 2, 2019) The Board of Directors of the Roper Center for Public Opinion Research at Cornell University is pleased to announce that the archive will expand its acquisitions policy to include recently developed survey methods including online non-probability samples. The addition of a Recently Developed Methods collection will result in a major expansion to the world's largest public opinion database. At the same time, the Roper Center is also introducing the Roper Center Transparency Project aimed at increasing disclosure and data sharing in the field of public opinion polling.

"Transparency is key to the new policy," said Gary Langer, president of Langer Research Associates and the Roper Board's Transparency and Acquisitions Committee Chair. "With its dual focus on expanded acquisitions and enhanced disclosure, the Center will take a leading role in encouraging the informed evaluation of newly developed methods by the research community."

The Recently Developed Methods Collection will include nonprobability online panels, interactive voice response polls, and other approaches.  This new collection will complement the Longstanding Methods Collection, allowing users to analyze both types of data while the Center preserves more data for future generations. See this video for a better understanding of how to access the RDM collection in Roper iPoll.

The Roper Center’s many data providers have always followed rigorous disclosure standards. With the Roper Center Transparency Project, starting in 2019, the Roper Center will keep track of even more methodological information that experts have identified as key to understanding polls. This information will allow researchers, news organizations and members of the public to identify critical methodological information that will enhance their understanding of polling and their use of the database.

 “The field of polling has long embraced data sharing and transparency as central values that improve research and spur innovation. By including recently developed survey methods and initiating the Roper Transparency Project, the Roper Center ensures that it will continue to play a central role in public opinion survey research, preserving and providing access to the public's voice in the era of big data,” said Peter Enns, Ph.D., Executive Director of the Roper Center and Associate Professor in the Department of Government at Cornell University.

This Project builds on expansions to the data collection and improvements to the user interface that Roper Center has undertaken at Cornell University. The number of ongoing data providers to Roper Center has doubled since 2015, and includes major media, nonprofit and academic pollsters. The Roper Center has also improved the user experience by enhancing search capabilities and on-line data analysis tools.

Founded in 1947 by Elmo Roper, the Roper Center for Public Opinion Research continues to play a crucial role in the advancement of the field of public opinion research.  The Center’s mission is to collect, preserve, and disseminate public opinion data; to serve as a resource to help improve the practice of survey research; and to broaden the understanding of public opinion through the use of survey data in the United States and around the world.  The digital archive, also known as iPOLL®, includes data from as early as 1935 and offers users nearly 800,000 questions and more than 25,000 datasets, expanding daily as questions and surveys are added to study records. In addition to iPOLL®, the Center retains a physical collection in its offices on the Cornell University campus in Ithaca, NY.  A 501 (c)(3), non-profit, the Roper Center is hosted at Cornell University.  Annually, the Roper Center Board of Directors recognizes professional contributions to the field of public opinion research by awarding the Warren J. Mitofsky Award. On the web at Inquiries to