- Category: Data Infrastructure, Education, Homeless and High-Needs, Labor, Methods, Safety Net
GUIDE FOR AGENCY LEADERSHIP Connecting Families to Benefits Using Linked Data
TECHNICAL HOW-TO GUIDE FOR DATA ANALYSTS Hashed Linkages for Administrative Datasets: A Technical How-to Guide
REPOSITORY OF SAMPLE CODE: Hashed Linkages
Linking government data between different agencies and departments is a powerful strategy to connect people to valuable benefits that they might otherwise miss. This toolkit provides step-by-step guidance to government leadership and their staff on how to develop and execute cross-departmental data linkages by focusing on a case study on increasing the take-up of anti-poverty tax credits.
To help the State of California understand who may be at risk of not receiving anti-poverty tax credits, the California Policy Lab (CPL) facilitated the first-time linkage of two individual-level datasets held by state agencies: one with safety-net enrollment data and one with state tax filing data. CPL served as a trusted third party by implementing a “hashed linkage” — linking data that was de-identified through “hashing” (a one-way encryption process) by each agency. By linking this data, we helped measure how many Californians receiving safety-net benefits were at risk of not receiving federal stimulus payments, the state Earned Income Tax Credit, and the advanced Child Tax Credit– resulting in millions of dollars of federal aid delivered to non-filing Californians.
As other states aim to replicate California’s efforts, this toolkit provides step-by-step guidance to help government staff and leadership who are interested in linking administrative data to increase the take-up of anti-poverty tax credits.
- Agency leadership can use Connecting Families to Benefits Using Linked Data to decide on the best legal pathways to linkage, assemble and manage a team of legal and data staff to execute a linkage, and identify and work with a third-party partner as needed.
- Data and research staff within and outside government can use Hashed Linkages for Administrative Datasets to execute a privacy-preserving linkage using cryptographic hashing.
- Sample hashing code is available on github for data analysts to adapt to their project
Linking data across previously siloed departments has great potential to break down programmatic silos between departments. For example, linking data across different safety-net programs such as SNAP, TANF, and unemployment insurance can help increase enrollment across programs. Linking health, housing, safety net, and criminal justice data can help further policy goals related to improving care coordination for the most vulnerable. Linking education data with financial aid, college enrollment, and safety-net data can help colleges and universities to understand how to help students meet basic needs and drive academic completion.
This toolkit is funded by the Bill & Melinda Gates Foundation and the National Science Foundation under Grant #2024283. The findings and conclusions contained within are those of the authors and do not necessarily reflect positions or policies of the Bill & Melinda Gates Foundation. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation. All errors should be attributed to the authors.