Premium
Two–step sequential sampling
Author(s) -
Moors J. J. A.,
Strijbosch L. W. G.
Publication year - 2002
Publication title -
statistica neerlandica
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.52
H-Index - 39
eISSN - 1467-9574
pISSN - 0039-0402
DOI - 10.1111/1467-9574.05000
Subject(s) - sample size determination , sample (material) , statistics , mathematics , variance (accounting) , extension (predicate logic) , sampling (signal processing) , variable (mathematics) , econometrics , computer science , mathematical analysis , chemistry , accounting , filter (signal processing) , chromatography , business , computer vision , programming language
Choosing the sample size in advance is a familiar problem: often, additional observations appear to be desirable. The final sample size then becomes a random variable, which has rather serious consequences. Two such sample extension situations will be considered here. In the first situation, the observed sample variance determines whether or not to double the original sample size. In the second situation, the variances observed in two independent samples are compared; their ratio determines the number of additional observations.