docs/lc.stdmean.ws.md

In cwendorf/dgb: DGB

Standardized Linear Contrast of Means (Within Subjects)

ci.lc.stdmean.ws

Computes confidence interval for a population standardized linear contrast of means in a within-subjects design (assumes equal correlations).

Arguments: - alpha: alpha level for 1-alpha confidence - m: vector of sample means - sd: vector of sample standard deviations - cor: average of sample correlations - n: sample size - h: vector of contrast coefficients

Values: - estimate, SE, lower limit, upper limit

alpha = .05
m = c(33.5, 37.9, 38.0)
sd = c(2.65, 2.90, 3.25)
cor = .82
n = 20
h = c(-.5, -.5, 1)
ci.lc.stdmean.ws(alpha, m, sd, cor, n, h)

##                           Estimate        SE        LL       UL
## Equal Var & Cor Assumed: 0.7813463 0.1614220 0.4649650 1.097728
## Only Equal Cor Assumed:  0.7813463 0.1580369 0.4715997 1.091093

size.ci.lc.stdmean.ws

Computes sample size required to estimate a standardized linear contrast of population means with desired precision in a within-subjects design.

Arguments: - alpha: alpha level for 1-alpha confidence - d: planning value of standardized linear contrast - cor: planning value of smallest correlation - w: desired confidence interval width - h: vector of contrast coefficients

Values: - required sample size

alpha = .05
d = 1
cor= .7
w = .6
h = c(.5, .5, -.5, -.5)
size.ci.lc.stdmean.ws(alpha, d, cor, w, h)

##      [,1]
## [1,]   26

cwendorf/dgb documentation built on May 3, 2022, 9:35 p.m.