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Confidence interval for the parameter of the one-sample sign test

Source: R/statpsych1.R
ci.sign.Rd

Computes an adjusted Wald interval for the population proportion of quantitative scores that are greater than the null hypothesis value of the population median in a one-sample sign test. This proportion is a measure of effect size that can be reported along with the sign test.

Usage

ci.sign(alpha, y, h)

Arguments

alpha

alpha level for 1-alpha confidence

y

vector of y scores

h

null hypothesis value for population median

Value

Returns a 1-row matrix. The columns are:

  • Estimate - adjusted estimate of proportion

  • SE - adjusted standard error

  • LL - lower limit of adjusted Wald confidence interval

  • UL - upper limit of adjusted Wald confidence interval

References

Agresti A, Coull BA (1998). “Approximate is better than 'exact' for interval estimation of binomial proportions.” The American Statistician, 52(2), 119–126. ISSN 0003-1305, doi:10.1080/00031305.1998.10480550 .

Examples

y <- c(30, 20, 15, 10, 10, 60, 20, 25, 20, 30, 10, 5, 50, 40, 20, 10,
        0, 20, 50)
ci.sign(.05, y, 9)
#>  Estimate        SE        LL        UL
#>  0.826087 0.0790342 0.6711828 0.9809911

# Should return:
# Estimate        SE        LL        UL
# 0.826087 0.0790342 0.6711828 0.9809911