Compares and combines Pearson or partial correlations in original and follow-up studies

Source: R/meta_rep.R

This function can be used to compare and combine Pearson or partial correlations from an original study and a follow-up study. The confidence level for the difference is 1 – 2*alpha, which is recommended for equivalence testing.

replicate.cor(alpha, cor1, n1, cor2, n2, s)

Arguments

alpha

alpha level for 1-alpha confidence

cor1

estimated correlation in original study

n1

sample size in original study

cor2

estimated correlation in follow-up study

n2

sample size in follow-up study

s

number of control variables in each study (0 for Pearson)

Value

A 4-row matrix. The rows are:

  • Row 1 summarizes the original study

  • Row 2 summarizes the follow-up study

  • Row 3 estimates the difference in correlations

  • Row 4 estimates the average correlation

The columns are:

  • Estimate -correlation estimate (single study, difference, average)

  • SE - standard error

  • z - t-value for rows 1 and 2; z-value for rows 3 and 4

  • p - p-value

  • LL - lower limit of the confidence interval

  • UL - upper limit of the confidence interval

References

Bonett DG (2021). “Design and analysis of replication studies.” Organizational Research Methods, 24(3), 513--529. ISSN 1094-4281, doi:10.1177/1094428120911088 .

Examples

replicate.cor(.05, .598, 80, .324, 200, 0)
#>                       Estimate         SE        z            p        LL
#> Original:                0.598 0.07320782 6.589418 4.708045e-09 0.4355043
#> Follow-up:               0.324 0.06376782 4.819037 2.865955e-06 0.1939787
#> Original - Follow-up:    0.274 0.09708614 2.633335 8.455096e-03 0.1065496
#> Average:                 0.461 0.04854307 7.634998 2.264855e-14 0.3725367
#>                              UL
#> Original:             0.7227538
#> Follow-up:            0.4428347
#> Original - Follow-up: 0.4265016
#> Average:              0.5411607

# Should return:
#                       Estimate         SE        z            p        LL        UL
# Original:                0.598 0.07320782 6.589418 4.708045e-09 0.4355043 0.7227538
# Follow-up:               0.324 0.06376782 4.819037 2.865955e-06 0.1939787 0.4428347
# Original - Follow-up:    0.274 0.09708614 2.633335 8.455096e-03 0.1065496 0.4265016
# Average:                 0.461 0.04854307 7.634998 2.264855e-14 0.3725367 0.5411607