摘要(英) |
In statistical analysis, the capital purpose of determining sample size is to obtain enough sample size in order to achieve the probability of type one error and power. Before analyzing, we usually take a small sample size to estimate parameters in model, then to calculate sample size. But, if the model is wrong, the sample size is incorrect. Thus, the probability of type one error and power will not achieve the goal.
Royall & Tsou (2003) brought up robust likelihood function., Even we don’t know the real distribution of data, robust likelihood function will provide correct information of parameters of interest when sample size is large. And Tsou (2004) spread it to general linear model.
The paper use the method of robust regression to determine sample size, and compare sample size in robust normal model, robust gamma model and robust inverse Gaussian model. |
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