| ci.stdmean.ps {statpsych} | R Documentation |
Confidence intervals for a paired-samples standardized mean difference
Description
Computes confidence intervals for a population standardized mean difference in a paired-samples design. A square root unweighted variance standardizer and single measurement standard deviation standardizers are used. Equality of variances is not assumed.
Usage
ci.stdmean.ps(alpha, m1, m2, sd1, sd2, cor, n)
Arguments
alpha |
alpha level for 1-alpha confidence |
m1 |
estimated mean for measurement 1 |
m2 |
estimated mean for measurement 2 |
sd1 |
estimated standard deviation for measurement 1 |
sd2 |
estimated standard deviation for measurement 2 |
cor |
estimated correlation between measurements |
n |
sample size |
Value
Returns a 3-row matrix. The columns are:
Estimate - estimated standardized mean difference
adj Estimate - bias adjusted standardized mean difference estimate
SE - standard error
LL - lower limit of the confidence interval
UL - upper limit of the confidence interval
References
Bonett DG (2008). “Confidence intervals for standardized linear contrasts of means.” Psychological Methods, 13(2), 99–109. ISSN 1939-1463, doi:10.1037/1082-989X.13.2.99.
Examples
ci.stdmean.ps(.05, 110.4, 102.1, 15.3, 14.6, .75, 25)
# Should return:
# Estimate adj Estimate SE LL UL
# Unweighted standardizer: 0.5550319 0.5433457 0.1609934 0.2394905 0.8705732
# Measurement 1 standardizer: 0.5424837 0.5253526 0.1615500 0.2258515 0.8591158
# Measurement 2 standardizer: 0.5684932 0.5505407 0.1692955 0.2366800 0.9003063