The short answer is Yes. If you reject the null hypothesis based on that p-value, then by definition you had enough power to do that. This is because there is a precise inverse relationship between the p-value and the "observed" power, once you fix the effect size and the sample size. In other words, your post-hoc power analysis would be a simple re-statement of the p-value. There is no extra information that can be gained from such an analysis. See:
The American Statistician, February 2001, Vol. 55, No. 1, pp 19-24 Don't bother with your power analysis, unless you are planning a new experiment. Simon. On Tue, 2009-10-06 at 13:49 -0700, SNN wrote: > Hi, > > I have used multiple linear regression on a data set and one if the > regressor was significant with a p-value =0.01 > > I need to calculate the power for a multiple linear regression. i.e. do I > have enough power to believe the above p-value? > > > > -- Simon Blomberg, BSc (Hons), PhD, MAppStat. Lecturer and Consultant Statistician School of Biological Sciences The University of Queensland St. Lucia Queensland 4072 Australia Room 320 Goddard Building (8) T: +61 7 3365 2506 http://www.uq.edu.au/~uqsblomb email: S.Blomberg1_at_uq.edu.au Policies: 1. I will NOT analyse your data for you. 2. Your deadline is your problem. Statistics is the grammar of science - Karl Pearson ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
