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Evaluating the Effect of Training on Wages in the Presence of Noncompliance, Nonemployment, and Missing Outcome Data
Evidence is found that the effects of a job training program, Job Corps, should have been better targeted, in the sense of being designed differently for different groups of people, and specific suggestions are offered.
Using Secondary Outcomes to Sharpen Inference in Randomized Experiments With Noncompliance
We develop new methods for analyzing randomized experiments with noncompliance and, by extension, instrumental variable settings, when the often controversial, but key, exclusion restriction
The effects of trading activity on market volatility
The paper re-examines the question of excessive implied persistence of volatility estimates when GARCH type models are used. Ten actively traded US stocks are considered and as already established in
Exploiting instrumental variables in causal Inference with nonignorable outcome nonresponse using principal stratification
In this paper we consider a specific post-treatment complication that may arise in both randomized and observational studies, namely the problem of nonignorable nonresponse on an outcome variable.
The fragility of standard inferential approaches in principal stratification models relative to direct likelihood approaches
This work explores the use of a direct likelihood approach for parsimonious model selection and proposes comparing values of scaled maximized likelihood functions under competitive models to select preferred models.
Early News is Good News: The Effects of Market Opening on Market Volatility
In this paper, we examine the characteristics of market opening news and its impact on the estimated coefficients of the conditional volatility models of the GARCH class. We find that the differences
Identification of Principal Causal Effects Using Additional Outcomes in Concentration Graphs
Unless strong assumptions are made, nonparametric identification of principal causal effects can only be partial and bounds (or sets) for the causal effects are established. In the presence of a