FAQ

How is the Virtual Data Enclave different from the Federal Statistical Research Data Center (FSRDC) network?

  1. The CJARS VDE environment is a secure, remote analysis platform that you can access from your home or office. International researchers are welcome to work on our system.
  2. The newest CJARS vintages are accessible to users up to 12 to 18 months faster through the VDE compared to the FSRDC system.
  3. Federally held socio-economic data is not available on the VDE, but you are welcome to bring your own data to the server, which our team will be happy to help link to the CJARS records. We also have some exciting partnerships with other data providers that will be available to VDE users, which will be announced in the coming years. Stay tuned.

How do I start a new project on the Virtual Data Enclave?

Check out this link to find out more information on starting your next CJARS project on the VDE.

How can I track the progress of my access request to the Virtual Data Enclave?

We developed a Data Access Checklist that you are welcome to use track your status on each of the steps required to acquire access.

Can I integrate my own data into the Virtual Data Enclave? What types of linkages are available?

Yes! We would be happy to work with you to support integration of your auxiliary data into the VDE. CJARS has developed a sophisticated record linkage model for person-level matching, which we can apply to your data. Alternatively, we can also execute alternative matching strategies when preferred. Reach out to our team at [email protected] to start a conversation with us about what you might be envisioning. This service will become available January 1st, 2026.

How many people can work on a project on the Virtual Data Enclave at a given time?

VDE subscriptions automatically support 2 active users at a given time. Additional users can be added to your project space for a fee, up to a maximum of 4 total active users at a given time.

Is the CJARS data on the Virtual Data Enclave the same as what is available via the Federal Statistical Research Data Center (FSRDC) network?

Not exactly. While both secure research environments draw from the same underlying CJARS vintages, the available data differs on a couple margins. First, we are still in the process of updating all of our data use agreements with data providers to authorize research activity on the VDE. Until this is complete, a few jurisdictions have data withheld on the VDE that is otherwise accessible via the FSRDC network. We are working to update this legal paperwork over the next year. Second, newer CJARS vintages are uploaded to the VDE at a faster cadence than the FSRDC system. Since data integration of CJARS data at the Census Bureau is a resource intensive and time-consuming process, we are currently aiming to upload 1 vintage per year to the FSRDC system. Data production for the VDE can be deployed much faster, meaning we are aiming to produce 2-4 vintages per year for VDE researchers. That means VDE researchers will always have first access to the latest CJARS data acquisitions and the highest quality data product.

What programming languages are supported on the Virtual Data Enclave?

We currently support Stata 18 MP-64, R and R Studio, SAS 9.4, and Python (Anaconda 3 installation). If there is something you would like to use that we don’t currently offer, please reach out to us at [email protected] so we can explore whether we can support your research.

Is the data I need available on the VDE?

Check out the VDE Data Documentation Supplement to find out more information about VDE coverage. We are continuously working with data providers to expand our data coverage.

How do I get my research out of the Virtual Data Enclave?

We have set up a simplified statistical disclosure review process to expedite and streamline getting your research off of the VDE. Research output can be submitted on an ongoing basis. It will then be reviewed for consistency with minimal cell size requirements, conformance with your originally proposed research, geographic aggregation, etc. A full list of disclosure requirements is available in the CJARS VDE Disclosure Avoidance Handbook. We aim to get all requested VDE output that conforms with disclosure requirements returned to researchers with 10 business days.

What happens if my research changes after I’ve already started working on the Virtual Data Enclave? Can I start a new project in my existing workspace?

You can pursue multiple research projects within a single workspace. If your project has substantively changed or if you are starting a new research effort entirely, we may need to seek reapproval for your new research from some of our data providers before we can allow you to remove statistical output from the VDE through the statistical disclosure process. If you’re thinking about changing your research from your original proposal, reach out to us at [email protected] to figure out if a revision of your Project Proposal Form is warranted.

I just submitted a paper to a peer reviewed journal, and I don’t anticipate needing to log in to the VDE for the next few months. Can I hibernate my account if I still have paid months of server access remaining?

Yes, you can temporarily suspend your account in order to preserve your paid access for future use. Note that, however, all users on your project will have access suspended for the duration of your project hibernation. Reach out to us at [email protected] if this is something you’re interested in so we can share more details about the process.

I anticipate needing significant computing power for my intended research. How much bandwidth will I get access to on the Virtual Data Enclave?

The standard project entitles users to 200 GB of RAM and each project space can use up to 500 GB of storage. If you anticipate needing more bandwidth from the VDE, please reach out to us at [email protected] so we can discuss further.

How much does it cost to work on the Virtual Data Enclave? How do I pay for site access?

You can find more information at this link. We will collect the relevant information from you as part of the project application process in order to set up payment; you will not be charged for site access until your project has been approved.

How can I contribute criminal justice data to a future release of the VDE?

Thank you for your interest! We always appreciate new data partnerships to expand the VDE’s coverage and help fuel future research. If you are a researcher with data you’d like to share, or represent a criminal justice agency or organization with relevant records, please contact our data collection team at [email protected].