Tutorial [Power / Sample Size]

posted by Alyssa – Malaysia, 2020-05-08 08:48 (1004 d 22:18 ago) – Posting: # 21406
Views: 6,673

Dear Helmut,

Thanks for the detailed tutorial!

I was trying to follow your command and out in the powerTOST, however, i cant get the sample size estimation. May i know what has gone wrong? Thank you ~


# partial replicate, 3- and 4-period full replicate designs
> designs <- c("2x3x3", "2x2x3", "2x2x4")
> # desired powers
> target  <- c(0.80, 0.85, 0.90)
> # assign a data.frame of results
> res     <- data.frame(design = rep(designs, each = length(target)),
+                       target = target, n = NA, power = NA)
> # loop over the rows, apply the defaults:
> # T/R-ratio 0.90, 100,000 simulated studies
> for (j in 1:nrow(res)) {
+   res[j, 3:4] <- sampleN.scABEL(CV = CV, design = res$design[j],
+                                 targetpower = res$target[j],
+                                 print = FALSE, details = FALSE)[8:9] + }
Error in sampleN.scABEL(CV = CV, design = res$design[j], targetpower = res$target[j],  :
  could not find function "sampleN.scABEL"
> print(res, row.names = FALSE)
 design target  n power
  2x3x3   0.80 NA    NA
  2x3x3   0.85 NA    NA
  2x3x3   0.90 NA    NA
  2x2x3   0.80 NA    NA
  2x2x3   0.85 NA    NA
  2x2x3   0.90 NA    NA
  2x2x4   0.80 NA    NA
  2x2x4   0.85 NA    NA
  2x2x4   0.90 NA    NA



Edit: Code and results BBCoded; see also this post #10[Helmut]

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