size.ci.prop1 {statpsych} | R Documentation |
Computes the sample size required to estimate a single proportion with desired confidence interval precision. Set the proportion planning value to .5 for a conservatively large sample size.
size.ci.prop1(alpha, p, w)
alpha |
alpha level for 1-alpha confidence |
p |
planning value of proportion |
w |
desired confidence interval width |
Returns the required sample size
size.ci.prop1(.05, .4, .2) # Should return: # Sample size # [1,] 93