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Compares and combines effect sizes in original and follow-up studies

Source: R/meta_rep.R
replicate.gen.Rd

This function can be used to compare and combine any effect size using the effect size estimate and its standard error from the original study and the follow-up study. The confidence level for the difference is 1 – 2*alpha, which is recommended for equivalence testing.

For more details, see Chapter 4 of Bonett (2021, Volume 5).

Usage

replicate.gen(alpha, est1, se1, est2, se2)

Arguments

alpha

alpha level for 1-alpha confidence

est1

estimated effect size in original study

se1

effect size standard error in original study

est2

estimated effect size in follow-up study

se2

effect size standard error in follow-up study

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 effect sizes

  • Row 4 estimates the average effect size

Columns are:

  • Estimate - effect size estimate (single study, difference, average)

  • SE - standard error

  • z - z-value

  • 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 .

Bonett DG (2021). Statistical Methods for Psychologists, Vol 1-5, https://dgbonett.sites.ucsc.edu/.

Examples

replicate.gen(.05, .782, .210, .650, .154)
#>                       Estimate        SE     z     p         LL        UL
#> Original:                0.782 0.2100000 3.724 0.000  0.3704076 1.1935924
#> Follow-up:               0.650 0.1540000 4.221 0.000  0.3481655 0.9518345
#> Original - Follow-up:    0.132 0.2604151 0.507 0.612 -0.2963446 0.5603446
#> Average:                 0.716 0.1302075 5.499 0.000  0.4607979 0.9712021

# Should return: 
#                       Estimate        SE     z     p         LL        UL
# Original:                0.782 0.2100000 3.724 0.000  0.3704076 1.1935924
# Follow-up:               0.650 0.1540000 4.221 0.000  0.3481655 0.9518345
# Original - Follow-up:    0.132 0.2604151 0.507 0.612 -0.2963446 0.5603446
# Average:                 0.716 0.1302075 5.499 0.000  0.4607979 0.9712021