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Comment on "The Effect of Unions on Earnings and Earnings on Unions: A Mixed Logit Approach."
Olsen, Randall J, (1978)
Distributional Tests for Selectivity Bias and a More Robust Likelihood Estimator.
Olsen, Randall J, (1982)
The Effects of Salaries and Opportunity Costs on Duration in Teaching: Evidence from Michigan.
Murnane, Richard J, (1989)