FAS

JASON on Quantifications of Margins and Uncertainties

05.03.06 | 1 min read | Text by Steven Aftergood

The latest study by the JASON scientific advisory panel to be approved for public release has the forbidding title “Quantifications of Margins and Uncertainties” (pdf).

The meaning of this term is somewhat elusive, as discussed in the report, but it involves a methodology for assessing the reliability of complex technical systems, and specifically the performance and safety of the U.S. nuclear stockpile in the absence of nuclear explosive testing.

After a lengthy review process, the Department of Energy’s National Nuclear Security Administration released the March 2005 report in its entirety in response to a Freedom of Information Act request from the Federation of American Scientists.

See “Quantifications of Margins and Uncertainties,” March 23, 2005.

The Government Accountability Office (GAO) relied on the JASON report in a recent study on the nuclear weapons stockpile that also included a relatively clear description of QMU.

See “Nuclear Weapons: NNSA Needs to Refine and More Effectively Manage Its New Approach for Assessing and Certifying Nuclear Weapons” (pdf), GAO Report No. GAO-06-261, February 2006.

The somewhat mysterious JASON panel was the subject of Ann Finkbeiner’s well-received new book, “The JASONs: The Secret History of Science’s Postwar Elite.”

publications
See all publications
Education & Workforce
day one project
Policy Memo
Investing in Young Children Strengthens America’s Global Leadership

Supporting children’s development through health, nutrition, education, and protection programs helps the U.S. achieve its national security and economic interests, including the Administration’s priorities to make America “safer, stronger, and more prosperous.”

10.23.25 | 9 min read
read more
Education & Workforce
day one project
Policy Memo
AI Implementation is Essential Education Infrastructure

To strengthen federal–state alignment, upcoming AI initiatives should include three practical measures: readiness assessments before fund distribution, outcomes-based contracting tied to student progress, and tiered implementation support reflecting district capacity.

10.22.25 | 9 min read
read more
Environment
Press release
Bipartisan Fix Our Forests Act (S. 1462) Clears Senate Committee, a Crucial Step Forward for Wildfire Resilience

“FAS is very pleased to see the Fix Our Forests Act, S. 1426, advance out of Committee. We urge the Senate to act quickly to pass this legislation and to ensure that federal agencies have the capacity and resourcing they need to carry out its provisions.”

10.22.25 | 2 min read
read more
Government Capacity
Blog
Blue Sky Thinking to Reimagine and Reinvigorate Government Effectiveness

Using visioning, world-building, scenario planning, and other foresight tools, participants set aside today’s constraints to design blue-sky models of a future American government.

10.21.25 | 13 min read
read more