Confidence interval for a linear contrast of parameters in a between-subjects design

Source: R/statpsych2.R

Computes the estimate, standard error, and approximate confidence interval for a linear contrast of any type of parameter (e.g., quartile, logistic regression slope, path coefficient) where each parameter value has been estimated from a different sample. The parameter values are assumed to be of the same type (e.g., all unstandardized path coefficients) and their sampling distributions are assumed to be approximately normal.

ci.lc.gen.bs(alpha, est, se, v)

Arguments

alpha

alpha level for 1-alpha confidence

est

vector of parameter estimates

se

vector of standard errors

v

vector of contrast coefficients

Value

Returns a 1-row matrix. The columns are:

  • Estimate - estimate of linear contrast

  • SE - standard error of linear contrast

  • LL - lower limit of confidence interval

  • UL - upper limit of confidence interval

Examples

est <- c(3.86, 4.57, 2.29, 2.88)
se <- c(0.185, 0.365, 0.275, 0.148)
v <- c(.5, .5, -.5, -.5)
ci.lc.gen.bs(.05, est, se, v)
#>  Estimate        SE       LL       UL
#>      1.63 0.2573806 1.125543 2.134457

# Should return:
# Estimate        SE       LL       UL
#     1.63 0.2573806 1.125543 2.134457