Compute power of test or determine parameters to obtain target
power (same as power.anova.test
).
power.chisq.test(n = NULL, w = NULL, df = NULL, sig.level = 0.05, power = NULL)
total number of observations.
effect size.
degree of freedom (depends on the chosen test.
Significance level (Type I error probability).
Power of test (1 minus Type II error probability).
Object of class "power.htest", a list of the arguments (including the computed one) augmented with 'method' and 'note' elements.
Exactly one of the parameters w
, n
, power
or
sig.level
must be passed as NULL, and this parameter is
determined from the others. Note that the last one has non-NULL
default, so NULL
must be explicitly passed, if you want to compute
it.
Cohen, J. (1988) Statistical power analysis for the behavioral sciences (2nd ed.) Hillsdale, NJ: Lawrence Erlbaum.
# NOT RUN {
## Exercise 7.1 P. 249 from Cohen (1988)
power.chisq.test(w=0.289, df=(4-1), n=100, sig.level=0.05)
## Exercise 7.3 p. 251
power.chisq.test(w=0.346, df=(2-1)*(3-1), n=140, sig.level=0.01)
## Exercise 7.8 p. 270
power.chisq.test(w=0.1, df=(5-1)*(6-1), power=0.80, sig.level=0.05)
# }
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