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Computes a confidence interval for a population reliability coefficient such as Cronbach's alpha or McDonald's omega using an estimate of the reliability and its standard error. The standard error can be a robust standard error or bootstrap standard error obtained from an SEM program. Use ci.cronbach for Cronbach's alpha if parallel measurements can be assumed.

Usage

ci.reliability(alpha, rel, se, n)

Arguments

alpha

alpha level for 1-alpha confidence

rel

estimated reliability

se

standard error of reliability

n

sample size

Value

Returns a 1-row matrix. The columns are:

  • Estimate - estimated reliability (from input)

  • LL - lower limit of the confidence interval

  • UL - upper limit of the confidence interval

Examples

ci.reliability(.05, .88, .0147, 100)
#>  Estimate        LL        UL
#>      0.88 0.8489612 0.9065575

# Should return:
# Estimate         LL        UL
#     0.88  0.8489612 0.9065575