A5. Computing the Power of Statisical Tests

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Updated Notes

Some thoughful comments/corrections on our discssion of power for detecting a QYL are offered in the following pdf file from Peter Visscher, Ian White and Andrew Carothers (Edinburgh), Feb 2003.


For calculation of central and noncentral F and chi^2 values (as well as many other distributions), I really like the (FREE!) R Statistical Programming Language. Details:

The R Project for statistical Computing website

US Mirror site for downloading R. Current versions for

An Introduction of R (Walsh notes)

  1. R as a basic statistical calculator for obtaining p values and plotting probability distributions (6 page pdf file). [ posted 28 Dec. 2001 ]
  2. Power Calculations in R (4 page pdf file). [ posted 18 Jan 2002 ]

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Created 25 February 1995, last updated 31 Jan 2002

Bruce Walsh. jbwalsh@u.arizona.edu . Comments welcome.