Sample Allocation and Stratification
نویسنده
چکیده
منابع مشابه
Systematic analysis of design and stratification for phase III trials in first‐line advanced non‐small cell lung cancer
BACKGROUND A recent study reviewed phase III trials of first-line advanced non-small cell lung cancer (NSCLC) conducted from 1981 to 2010, and provided trends in the study outcome. However, such trials have never been analyzed in detail for design and stratification factors. METHODS Phase III studies of systemic treatment for first-line advanced or metastatic NSCLC published in English litera...
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When considering sample stratification by several variables, we often face the case where the expected number of sample units to be selected in each stratum is very small and the total number of units to be selected is smaller than the total number of strata. These stratified sample designs are specifically represented by the tabular arrays with real numbers, called controlled selection problem...
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