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Confidence interval for a paired-samples mean ratio

Source: R/statpsych1.R
ci.ratio.mean.ps.Rd

Compute a confidence interval for a ratio of population means of ratio-scale measurements in a paired-samples design. Equality of variances is not assumed.

For more details, see Section 4.4 of Bonett (2021, Volume 1)

Usage

ci.ratio.mean.ps(alpha, y1, y2)

Arguments

alpha

alpha level for 1-alpha confidence

y1

vector of measurement 1 scores

y2

vector of measurement 2 scores (paired with y1)

Value

Returns a 1-row matrix. The columns are:

  • Mean1 - estimated mean for measurement 1

  • Mean2 - estimated mean for measurement 2

  • Mean1/Mean2 - estimate of mean ratio

  • LL - lower limit of the confidence interval

  • UL - upper limit of the confidence interval

References

Bonett DG, Price RM (2020). “Confidence intervals for ratios of means and medians.” Journal of Educational and Behavioral Statistics, 45(6), 750–770. doi:10.3102/1076998620934125 .

Bonett DG (2021). Statistical Methods for Psychologists https://dgbonett.sites.ucsc.edu/.

Examples

y1 = c(76.41, 66.91, 81.06, 74.78, 83.76, 89.31, 78.78, 87.06, 82.61, 76.74, 88.33, 86.18)
y2 = c(59.85, 60.64, 84.86, 68.16, 71.53, 86.18, 67.30, 65.46, 83.50, 66.76, 88.37, 65.02)
ci.ratio.mean.ps(.05, y1, y2)
#>     Mean1   Mean2 Mean1/Mean2       LL       UL
#>  80.99417 72.3025    1.120213 1.040747 1.205745

# Should return:
#    Mean1   Mean2 Mean1/Mean2       LL       UL
# 80.99417 72.3025    1.120213 1.040747 1.205745