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Recurrent events are frequently observed in biomedical studies, and often more than one type of event is of interest. Follow-up time may be censored due to loss to follow-up or administrative censoring. We propose a class of semi-parametric marginal means/rates models, with a general relative...
Persistent link: https://www.econbiz.de/10009477085
In this article, we formulate a semiparametric model for counting processes in which the effect of covariates is to transform the time scale for a baseline rate function. We assume an arbitrary dependence structure for the counting process and propose a class of estimating equations for the...
Persistent link: https://www.econbiz.de/10009477086
In biomedical studies, the event of interest is often recurrent and within-subject events cannot usually be assumed independent. In addition, individuals within a cluster might not be independent; for example, in multi-center or familial studies, subjects from the same center or family might be...
Persistent link: https://www.econbiz.de/10009477087
Asymptotic expansions for the null distribution of thelogrank statistic and its distribution under local proportionalhazards alternatives are developed in the case of iid observations.The results, which are derived from the work of Gu (1992) andTaniguchi (1992), are easy to interpret, and...
Persistent link: https://www.econbiz.de/10009477088
Murrayand Tsiatis (1996) described a weighted survival estimate thatincorporates prognostic time-dependent covariate informationto increase the efficiency of estimation. We propose a test statisticbased on the statistic of Pepe and Fleming (1989, 1991) thatincorporates these weighted survival...
Persistent link: https://www.econbiz.de/10009477089
We propose a profile conditional likelihood approach to handle missing covariates in the general semiparametric transformation regression model. The method estimates the marginal survival function by the Kaplan-Meier estimator, and then estimates the parameters of the survival model and the...
Persistent link: https://www.econbiz.de/10009477090
The Cox (1972) regression model is extended to include discrete and mixed continuous/discrete failure time data by retaining the multiplicative hazard rate form of the absolutely continuous model. Application of martingale arguments to the regression parameter estimating function show the...
Persistent link: https://www.econbiz.de/10009477091
Despite their widespread use as predictors of the spot price of oil, oil futures prices tend to be less accurate in the mean-squared prediction error sense than no-change forecasts. This result is driven by the variability of the futures price about the spot price, as captured by the oil futures...
Persistent link: https://www.econbiz.de/10009477106
We derive semiparametric methods for estimating and testing treatment effects when censored recurrent event data are available over multiple periods. These methods are based on estimating functions motivated by a working “mixed-Poisson” assumption under which conditioning can eliminate...
Persistent link: https://www.econbiz.de/10009477133
We consider Semiparametric regression for periodic longitudinal data. Parametric fixed effects are used to model the covariate effects and a periodic nonparametric smooth function is used to model the time effect. The within–subject correlation is modeled using subject-specific random effects...
Persistent link: https://www.econbiz.de/10009477134