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Development of an Individual-Tree Basal Area Increment Model using a Linear Mixed-Effects Approach
Published on: July 3, 2020
James J Heckman1, Daniel Schmierer, Sergio Urzua
1University of Chicago, University College Dublin Cowles Foundation, Yale University and the American Bar Foundation.
This study introduces new tests for instrumental variables (IV) models, addressing how individuals sort into treatments based on unobserved gains. Findings suggest sorting on unobserved gains is empirically relevant for estimating returns to schooling.
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