Bhattacharjee, Arnab (2004): A Simple Test for the Absence of Covariate Dependence in Hazard Regression Models.

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Abstract
This paper extends commonly used tests for equality of hazard rates in a twosample or ksample setup to a situation where the covariate under study is continuous. In other words, we test the hypothesis that the conditional hazard rate is the same for all covariate values, against the omnibus alternative as well as more specific alternatives, when the covariate is continuous. The tests developed are particularly useful for detecting trend in the underlying conditional hazard rates or changepoint trend alternatives. Asymptotic distribution of the test statistics are established and small sample properties of the tests are studied. An application to the e¤ect of aggregate Q on corporate failure in the UK shows evidence of trend in the covariate e¤ect, whereas a Cox regression model failed to detect evidence of any covariate effect. Finally, we discuss an important extension to testing for proportionality of hazards in the presence of individual level frailty with arbitrary distribution.
Item Type:  MPRA Paper 

Institution:  University of St Andrews 
Original Title:  A Simple Test for the Absence of Covariate Dependence in Hazard Regression Models 
Language:  English 
Keywords:  Covariate dependence; Continuous covariate; Twosample tests; Trend tests; Proportional hazards; Frailty/ unobserved heterogeneity; Linear transformation model 
Subjects:  C  Mathematical and Quantitative Methods > C4  Econometric and Statistical Methods: Special Topics > C41  Duration Analysis; Optimal Timing Strategies C  Mathematical and Quantitative Methods > C1  Econometric and Statistical Methods and Methodology: General > C14  Semiparametric and Nonparametric Methods: General C  Mathematical and Quantitative Methods > C1  Econometric and Statistical Methods and Methodology: General > C12  Hypothesis Testing: General 
Item ID:  3937 
Depositing User:  Arnab Bhattacharjee 
Date Deposited:  09. Jul 2007 
Last Modified:  19. Feb 2013 06:10 
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URI:  http://mpra.ub.unimuenchen.de/id/eprint/3937 