## Buffon's needle [Power / Sample Size]

Hi Nastia,

somehow I missed your post. Sorry.

» I was interested how it works on real data. […] That is in 26.42% successful studies post hoc power was less than 80%. Why not in 50%? I suppose it is connected with two facts: the real number of subjects is always greater than calculated because researches include drop-outs and there exists the restricted limit of minimum of subjects in the study.

Very interesting!

» P.S.
»  if (length(packages[!inst]) > 0) install.packages(packages[!inst])
» One needs "s" on the end of "package(s)"?

Yes. That’s how the function of library utils is called.
Try ?install.packages and ?install.package
Also packages[!inst] not package[!inst]. Corrected in the OP.

» cat("Results of", nsims, "simulated studies:\n")); summary(res)
» extra ")"?

THX, wrong! Corrected in the OP.

Dif-tor heh smusma 🖖
Helmut Schütz

The quality of responses received is directly proportional to the quality of the question asked. 🚮
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