Publication Type: Conference Paper/Unpublished Manuscript
Abstract: Quasi-instrumental variables are instruments that are not perfectly exogenous. I examine how different instrumental variable estimators are affected by using quasi-instruments instead of true instruments, with an application to campaign spending.

Publication Type: Abstract
Abstract: Objective: To determine if timing of OSCE performance affects overall scores and identify factors associated with intergroup variability in the OSCE scores.
Methods: A 3-station OSCE was conducted in one day for 136 second-year pharmacy students. Station 1 was patient education on proper insulin injection technique. Station 2 was warfarin dosage adjustment and counseling. Station 3 was recommendation to a physician on renal dosage adjustment. The students were divided into 4 groups. Groups 1 and 2 performed the OSCE in the morning, and groups 3 and 4 performed in the afternoon. To address the concern that the afternoon groups may unfairly benefit from sharing of OSCE content by the morning groups, the scores for the 4 groups were analyzed using the student t-test. The content of each OSCE station was also evaluated qualitatively to identify factors that may promote intergroup variability in performance.
Results: Group 4 performed significantly better in station 3 compared to group 1 (12.61±1.28 vs. 10.67±2.07, p<0.001) but performed significantly worse in station 1 (12.87±1.74 vs. 13.97±1.49, p=0.004). There were no significant intergroup differences for station 2. Station 1 required performance of a skill and station 2 required problem solving, while station 3 required communication of a specific knowledge with a correct answer.
Implications: Sharing of OSCE content seems to occur among students but does not always serve favorably for the latter groups. OSCEs requiring skill performance or problem solving minimize advantage to the latter groups even in the presence of information sharing.

Publication Type: Conference Paper/Unpublished Manuscript
Review Method: Peer Reviewed
Abstract: Quasi-instrumental variables are instruments that are not perfectly exogenous (Bartels 1991). In this paper, I examine how different instrumental variable estimators are affected by using quasi-instruments instead of true instruments. Using Monte Carlo methods, I explore the properties of 2SLS, LIML, and Jackknife estimators. I find that all estimators are seriously biased and inconsistent. I then use these methods to estimate the effect of spending on electoral success in U.S. Senate elections, using data from Gerber (1998).
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Publication Type: Conference Paper/Unpublished Manuscript
Abstract: Recent research examining judicial sentencing decisions has shown the need to further define the incarceration decision and expand the definition of judicial options when sentencing felony offenders (Holleran and Spohn, 2004; Harrington and Spohn, 2005). These prior findings suggest that the legal and extra-legal factors judges use to sentence felony offenders differ for the decision to incarcerate in jail versus prison. The present research extends this examination to the factors that influence sentence length with the more detailed definition of sentencing options. Our research examines the sentence length imposed for felony offenders sentenced to jail and prison separately, in a jurisdiction, Midwestern County, with an indeterminate sentencing system.

Publication Type: Conference Paper/Unpublished Manuscript
Abstract: The use of race and ethnicity as variables in research has been instrumental in identifying and documenting national health patterns, including substantial and persistent health disparities between population groups differentiated by racial and ethnic categories. However, despite decades of accumulated evidence, understanding of the processes and mechanisms leading to the observed health patterns and, most importantly, to racial and ethnic health disparities has remained inadequate. A handful of investigators have convincingly argued that the inadequate understanding and explanations of health inequalities are linked to the conceptual and methodological limitations that characterize the use of race and ethnicity as variables in health research.
The argument about the conceptual and methodological limitations associated with the use of the categories leave unexplored two paradoxes. First, despite the absence of conceptual and operational definitions of race and ethnicity, health researchers have managed to construct and use these categories as two instrumental variables. And second, despite the absence of conceptual and operational definitions, the use of race and ethnicity as variables in health research has facilitated the identification and documentation of national health patterns, including persistent racial and ethnic health disparities. The paradoxical use of race and ethnicity raise the question: how have health researchers managed to construct race and ethnicity as two instrumental variables? In this study, I provide an answer to this questions.