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Digital Preservation Policy


This document articulates the Digital Preservation Policy of the Roper Center for Public Opinion Research within the context of the Center’s mission. The Digital Preservation Policy formalizes the Center’s organizational commitment to ensuring sustainable access to materials the Center acquires through the development and evolution of a comprehensive digital preservation program. This policy emphasizes the central importance of the preservation function to the Roper Center Board of Directors, staff, and stakeholders.


This policy addresses all aspects of preservation of born-digital and digitized materials for which the Roper Center is the primary custodian. The Center accepts responsibility for preserving and facilitating informed access to materials in its holdings in accordance with the Acquisition Policy for the Roper Center for Public Opinion Research and agreements with data producers.


The overall direction and goals of the preservation program are fundamental to the fulfillment of the Roper Center’s mission, which is to collect, preserve, and disseminate public opinion data and metadata adequate to fully assess how such data were collected and produced; 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 abroad. The Center is committed to assuring the Center’s data producers and user base that the largest collection of polling and survey interview data in the world will be preserved and made accessible for the long term.


To ensure continued access to the intellectual output of the public opinion field, the Center’s commitment to preservation encompasses any actions necessary to ensure the utility and authenticity of digital material, maintain its independent understandability, and mitigate and/or reverse the effects of hardware and software obsolescence and media decay. The specific objectives of the Center’s digital preservation program are to:

  • Maintain comprehensive and responsive systems and processes that capture, manage, preserve, and make accessible digital public opinion research assets
  • Serve the needs of individual and institutional members, data producers, and the scholarly community by enabling persistent access to digital content over time
  • Employ robust, interoperable metadata management strategies to ensure that digital content can be provided to users while remaining readable, meaningful, and independently understandable
  • Ensure compliance with OAIS [1] and other digital preservation standards and practices
  • Adapt preservation strategies to incorporate the capabilities afforded by new and emerging technologies in cost-effective and responsible ways
  • Foster staff expertise in digital curation practices, procedures, and technologies
  • Participate in the development of digital preservation community standards and practice

Organizational Viability

The digital preservation function is integrated into the operations and planning of the Roper Center. The Center makes an explicit institutional commitment to preserve and make available acquired content.

Roles and Responsibilities

Acting on behalf of its member institutions, individual members, data producers, and the larger research community, the Roper Center has accepted responsibility for preserving the digital materials in its holdings. The management of the Center’s digital preservation program is accomplished through the collaborative efforts of all Center staff working in acquisition, processing, cataloging, information technology, and systems administration capacities. It is the responsibility of the Center’s administration and Board of Directors to commit to supporting an environment in which fulfillment of the objectives of the digital preservation program is regarded as a central function of the Center. This support includes providing adequate managerial and financial commitment to the development of a digital preservation program. 

Selection and Acquisition

The Acquisition Policy for the Roper Center for Public Opinion Research outlines the priorities and criteria for acquiring archival content at the Roper Center.

Financial Sustainability

Roper Center institutional and individual members make a financial commitment toward the sustainability of the Center’s preservation activities through annual membership dues. The Center fulfills its preservation responsibilities on behalf of its members, data producers, and the larger research community.

Cooperation and Collaboration

The Roper Center acknowledges digital preservation as an international, shared responsibility that must be addressed collaboratively among organizations that commit to digital preservation planning and provide digital preservation services. Therefore, the Center actively seeks out partnerships and opportunities to develop consortia with other data archives, digital repositories, public opinion and survey research associations, and data producers for digital preservation cooperation and collaboration.


The Roper Center faces some digital preservation challenges:

  • Technological change: New types of digital content and digital environments present new preservation challenges, and existing digital content faces the risk of obsolescence. The Center must maintain an awareness of and be responsive to continually changing technology.
  • Survey research industry change: The expansion of the Center’s acquisition policy to include studies conducted using experimental methodologies presents preservation challenges because it requires an increased capacity for storage, description, and management of archived content. The Center must commit to continually adapting systems and processes to handle rapid changes in sampling and data collection methods in the survey research industry in such a way that ensure its long-term understandability and informed reusability.
  • Changes in member needs: The ongoing usability of our materials for the Center’s primary user group—the members—is crucial to the success of the long-term preservation program. Center staff must be diligent in monitoring members’ adoption of new tools and research practices as well as publishing requirements to which they must adhere and respond to resulting changes in member needs in all preservation planning and practices.
  • Domain complexities: A lack of industry standards in describing materials and their relationships to one another presents challenges in maintaining and describing relationships between materials that must be preserved to ensure longterm usability of the data. The Center must remain vigilant in fulfilling its responsibility to strike the appropriate balance between normalizing across materials for usability purposes and maintaining the integrity of original deposits.

Technological and Procedural Suitability

Digital content in the Roper Center holdings currently consists of public opinion research data, requisite documentation to use and understand the data, marginal data, and secondary publications. Upon acquisition of data files, the Center uses professionally reasonable efforts to process the digital content to ensure that confidential information has not been included in the data, reviews the documentation for completeness and accuracy, generates metadata records, and produces archival and distribution versions of the data. The Center cannot guarantee that such efforts will be 100% effective and disclaims all warranties, expressed or implied, with respect to the content, quality, accuracy, or completeness of the data.

The Center establishes and maintains connections between data files, documentation, marginal data, and secondary publications based on provenance. To enable the Center to retain the ability to regenerate distribution formats over time, the Center archives the original digital content received, the normalized versions of files, and superseded versions of files that have been distributed. The Center’s infrastructure and documentation are compliant with the Data Documentation Initiative (DDI) standard [2] in all material respects. Staff will monitor and contribute to the development of new metadata standards and adopt standards that support the Center’s infrastructure and technology as they are proven valuable by the community. The Center has adopted normalization and migration as its primary digital preservation strategies.

Systems Administration and Security

The processing procedures for digital content at the Roper Center actively address the need for ensuring the accuracy and completeness of digital content through the careful comparison of documentation and files submitted and the generation of metadata and documentation for files. The Center ensures the authenticity and integrity of its digital content through the active and ongoing use of checksums [3] from receipt of digital content and throughout monthly fixity audits [4].

In addition to file level protocols, the Roper Center employs proactive security, redundancy, and backup measures in order to maintain and protect its digital assets and ensure long-term integrity. All core system resources are firewalled and actively monitored to prevent unauthorized or inadvertent access. Duplication of backend storage, critical server resources, and load-balanced frontend applications is provided across multiple, physical locations to address single point of failure. All physical locations are secured and provide redundant network and power, and digital assets are backed up nightly and securely stored off-site. 

Procedural Accountability

The Center is committed to a five-year audit cycle that will assess risks to the utility and authenticity of digital material, the maintenance of its independent understandability, and mitigation and/or reversal of the effects of hardware and software obsolescence and media decay. The Center will evaluate, measure, and adjust the policies and practices of the digital preservation program based on risk assessment as well as advances in the digital preservation research community. The Center will maintain a commitment to transparency in its policies and operations as its digital preservation program expands and evolves.

Frequency of Policy Review

Given the rapid evolution of technology and its implications for digital preservation, the Roper Center Board of Directors and Center staff will review this Policy every five years to ensure that it continues to serve the Center’s needs.


The Roper Center acknowledges the following contributions to digital preservation policy development and implementation that were consulted throughout the Center’s preservation planning process:

CCSDS. Reference Model for an Open Archival Information System (OAIS): Recommended Practice.

Data Documentation Initiative (DDI). DDI Version 2.1, 2005, last revised 2013.

Digital Preservation Coalition Handbook, 2012

Green, Ann G. “Developing a Digital Preservation Policy Framework.” Presented at Stewardship of Digital Assets Workshop, Morgan Library and Museum in conjunction with the Northeast Document Conservation Center. Funded by the Andrew W. Mellon Foundation. New York, NY. April 2013.

Green, Ann G. “A Review and Redesign of Roper Center Infrastructure: Final Report.” The Roper Center for Public Opinion Research. Funded by the Robert Wood Johnson Foundation. PI: Mark Abrahamson. March 2012.

Inter-university Consortium for Political and Social Research (ICPSR). Digital Preservation Policy Framework, 2007, last revised 2012.

The Odum Institute. Digital Preservation Policies, 2011.

Yale University Library. Policy for the Digital Preservation, 2005, last revised 2007

[1]  CCSDS, Reference Model for an Open Archival Information System (OAIS): Recommended Practice

[2] Data Documentation Initiative (DDI), DDI Version 2.1, 2005, last revised 2013

[3] “A checksum is an algorithmically-computed numeric value for a file or a set of files used to validate the state and content of the file for the purpose of detecting accidental errors that may have been introduced during its transmission or storage. The integrity of the data can be checked at any later time by recomputing the checksum and comparing it with the stored one. If the checksums match, the data was almost certainly not altered.” – National Digital Stewardship Alliance Glossary 

[4] “A fixity audit is a mechanism to verify that a digital object has not been altered in an undocumented manner. Checksums, message digests and digital signatures are examples of tools to run fixity checks. Fixity information, the information created by these fixity checks, provides evidence for the integrity and authenticity of the digital objects and are essential to enabling trust.” – National Digital Stewardship Alliance Glossary 

Approved by the Roper Center for Public Opinion Research Board of Directors  January 23, 2015