Bucky's Tuition Promise (BTP) at the University of Wisconsin-Madison offers generous financial aid to low-income, in-state students. Unlike many similar programs at other public universities, financial eligibility for BTP depends solely on a family's Adjusted Gross Income (AGI), rather than on...

We provide simple tests for selection on unobserved variables in the Vytlacil-Imbens-Angrist framework for Local Average Treatment Effects (LATEs). Our setup allows researchers not only to test for selection on either or both of the treated and untreated outcomes, but also to assess the...