R2ch {pwr2ppl}

Compute power for R2 change in Multiple Regression (up to three predictors) Requires correlations between all variables as sample size. Means, sds, and alpha are option. Also computes Power(All) Example code below for three predictors. Expand as needed for four or five

Description

Compute power for R2 change in Multiple Regression (up to three predictors) Requires correlations between all variables as sample size. Means, sds, and alpha are option. Also computes Power(All) Example code below for three predictors. Expand as needed for four or five

Usage

R2ch(
  ry1 = NULL,
  ry2 = NULL,
  ry3 = NULL,
  r12 = NULL,
  r13 = NULL,
  r23 = NULL,
  n = NULL,
  alpha = 0.05,
  my = 0,
  m1 = 0,
  m2 = 0,
  m3 = 0,
  s1 = 1,
  s2 = 1,
  s3 = 1,
  sy = 1
)

Arguments

ry1

Correlation between DV (y) and first predictor (1)

ry2

Correlation between DV (y) and second predictor (2)

ry3

Correlation between DV (y) and third predictor (3)

r12

Correlation between first (1) and second predictor (2)

r13

Correlation between first (1) and third predictor (3)

r23

Correlation between second (2) and third predictor (3)

n

Sample size

alpha

Type I error (default is .05)

my

Mean of DV (default is 0)

m1

Mean of first predictor (default is 0)

m2

Mean of second predictor (default is 0)

m3

Mean of third predictor (default is 0)

s1

Standard deviation of first predictor (default is 1)

s2

Standard deviation of second predictor (default is 1)

s3

Standard deviation of third predictor (default is 1)

sy

Standard deviation of DV (default is 1)

Value

Power for R2 change in Multiple Regression (up to three predictors)

Examples

R2ch(ry1=.40,ry2=.40,ry3=-.40, r12=-.15, r13=-.60,r23=.25,n=24)