Fernandez, Jose (2008): An Empirical Model of Learning under Ambiguity: The Case of Clinical Trials.
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In this paper, I present an empirical model of learning under ambiguity in the context of clinical trials. Patients are concern with learning the treatment effect of the experimental drug, but face the ambiguity of random group assignment. A two dimensional Bayesian model of learning is proposed to capture patients�beliefs on the treatment effect and group assignment. These beliefs are then used to predict patient attrition in clinical trials. Patient learning is demonstrated to be slower when taking into account group ambiguity. In addition, the model corrects for attrition bias in the estimated treatment effect.
|Item Type:||MPRA Paper|
|Original Title:||An Empirical Model of Learning under Ambiguity: The Case of Clinical Trials|
|Keywords:||clinical trials, learning, Bayesian, structural model, treatment effect|
|Subjects:||D - Microeconomics > D8 - Information, Knowledge, and Uncertainty
C - Mathematical and Quantitative Methods > C3 - Multiple or Simultaneous Equation Models; Multiple Variables > C31 - Cross-Sectional Models; Spatial Models; Treatment Effect Models; Quantile Regressions; Social Interaction Models
I - Health, Education, and Welfare > I1 - Health
|Depositing User:||Jose Fernandez|
|Date Deposited:||07. May 2008 04:52|
|Last Modified:||12. Feb 2013 21:53|
Ackerberg, D., "Advertising, Learning, and Consumer Choice in Experience Good Markets: A Structural Examination," International Economic Review, 44, 1007-1040 (2003).
Berkovec, James and Steven Stern (1991). �Job Exit Behavior of Older Men.�Econometrica. 59 (1): 189-210.
CDC Staff, "The Cost of AIDS and Other HIV Infections: Review of the Estimates." mimeo (1987).
Crawford, G. and Shum, M. (2005). �Uncertainty and Learning in Pharmaceutical Demand,�Econometrica, forthcoming.
Chan T. and Hamilton B. "Learning, Private Information and the Economic Evaluation of Randomized Experiments," (forthcoming, Journal of Political Economy, 2006).
DeGroot, M.H. . Optimal statistical decisions. McGraw-Hill, 1970
Erdem, T. and Keane, M. (1996). �Decision-Making Under Uncertainty: Capturing Dynamic Brand Choice Processes in Turbulent Consumer Goods Markets,�Marketing Science, 15, 1-20.
Hausman, J. and Wise, D. (1979) "Attrition Bias in Experimental and Panel Data: The Gary Income Maintenance Experiment," Econometrica, Vol. 47, No. 2. (Mar., 1979), pp. 455-474.
Heckman, J., Hohmann, N., and Smith, J. (2000). �Substitution and Dropout Bias in Social Experiments: A Study of an In�uential Social Experiment,�Quarterly Journal of Economics, CXV, 651-694.
Hrobjartsson, A. Gotzsche, P. C. (2001). "Is the Placebo Powerless? An Analysis of Clinical Trials Comparing Placebo with No Treatment," New England Journal of Medicine VOL 344; PART 21, pages 1594-1602
Kircsh, I., Moore, T., and Nicholas, S., "The Emperor�s New Drugs," Prevention & Treatment, Volume 5, Article 23, posted July 15, 2002
Malar, C. "The Estimation of Simultaneous Probability Models," Econometrica Vol 45, No. 7 (Oct. 1977)
Malani, A. "Identifying Placebo Effects with Data from Clinical Trials," Vol 114, Journal of Political Economy, p.236 (2006)
Malani, A., "Patient Enrollment in Medical Trials: Selection Bias in a Randomized Experiment," mimeo (October 2005)
Philipson, T. and Desimone, J. (1997). �Experiments and Subject Sampling,� Biometrika, 84, 619- 631.
A.H.P. Paes, A. Bakker and C.J. Soe-Agnie, "Measurement of patient compliance," Pharm World Sci 20(2): 73-77 (1998).
Stern, S., "Two Dynamic Discrete Choice Estimation Problems and Simulation Method Solutions," Review of Economics and Statistics, November 1994, 76(4): 695-702.
Volberding et. al., (1990). "Zidovudine in Asymptomatic Human Immunodeficiency Virus Infection." New England Journal of Medicine, Vol. 322, No. 14 (April). p. 941 - 949.