Umbrella Tests for Right-censored Survival Data
نویسندگان
چکیده
This paper considers the problem of testing for umbrella alternatives in the one-way layout when survival data are subject to random right censorship. Testing procedures based on two-sample weighted logrank statistics are suggested for both cases when the peak of the umbrella is known or unknown. The Pitman efficacy of the peak-known umbrella test is derived. A class of Lehmann and scale alternatives for which the peak-known umbrella test is optimal in the sense of Pitman efficacy is then obtained under the assumption of equal censorship. Moreover, the results of a Monte Carlo study to investigate the level and power performances of the proposed umbrella tests are presented. Finally, application of the proposed procedures to an appropriate data set is illustrated.
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