3 papers
econ.EM2026
What No First Stage Can Detect: Functional-Form Contamination in Linear IV
Parush Arora
Applied instrumental variables (IV) practice reports a first-stage F, now often the conditional F of Sanderson and Windmeijer (2016), and reads a large value as license to interpre…
econ.EM2026
Trading Scope for Credibility in Difference-in-Differences
Parush Arora, Abhishek Chand
When parallel trends fails for some treated cohorts but not others, the average treatment effect on the treated (ATT), an average over all of them, is exactly the target that becom…
econ.EM2026
Partial Homogeneity in Staggered Difference-in-Differences
Parush Arora, Rohan Wagle
In staggered difference-in-differences (DiD) designs, units enter treatment at different calendar times, so the treatment effect is not a single number but a set of Cohort-Average…