size.ci.mape {statpsych} | R Documentation |
Sample size for a mean absolute prediction error confidence interval
Description
Computes the sample size required to estimate a population mean absolute prediction error for a general linear model with desired confidence interval precision. Setting s = 0 gives the sample size requirement for a mean absolute deviation in a one-group design. This function assumes that the prediction errors have an approximate normal distribution.
Usage
size.ci.mape(alpha, mape, s, w)
Arguments
alpha |
alpha value for 1-alpha confidence |
mape |
mean absolute prediction error planning value |
s |
number of predictor variables |
w |
desired confidence interval width |
Value
Returns the required sample size
Examples
size.ci.mape(.05, 4.5, 5, 2)
# Should return:
# Sample size
# 57
[Package statpsych version 1.6.0 Index]