R/meta_ave.R
meta.ave.gen.cc.Rd
Computes the estimate, standard error, and confidence interval for a weighted average effect from two or more studies using the constant coefficient (fixed-effect) meta-analysis model.
meta.ave.gen.cc(alpha, est, se, bystudy = TRUE)
alpha level for 1-alpha confidence
vector of parameter estimates
vector of standard errors
logical to also return each study estimate (TRUE) or not
Returns a matrix. The first row is the average estimate across all studies. If bystudy is TRUE, there is 1 additional row for each study. The matrix has the following columns:
Estimate - estimated effect size
SE - standard error
LL - lower limit of the confidence interval
UL - upper limit of the confidence interval
The weighted average estimate will be biased regardless of the number of studies or the sample size in each study. The actual confidence interval coverage probability can be much smaller than the specified confidence level when the population effect sizes are not identical across studies.
The constant coefficient model should be used with caution, and the varying coefficient methods in this package are the recommended alternatives. The varying coefficient methods do not require effect-size homogeneity across the selected studies. This constant coefficient meta-analysis function is included in the vcmeta package primarily for classroom demonstrations to illustrate the problematic characteristics of the constant coefficient meta-analysis model.
Hedges LV, Olkin I (1985). Statistical methods for meta-analysis. Academic Press, New York. ISBN 01-233-63802.
Borenstein M, Hedges LV, Higgins JP, Rothstein HR (2009). Introduction to meta-analysis. Wiley, New York.
est <- c(.022, .751, .421, .287, .052, .146, .562, .904)
se <- c(.124, .464, .102, .592, .864, .241, .252, .318)
meta.ave.gen.cc(.05, est, se, bystudy = TRUE)
#> Estimate SE LL UL
#> Average 0.3127916 0.06854394 0.17844794 0.4471352
#> Study 1 0.0220000 0.12400000 -0.22103553 0.2650355
#> Study 2 0.7510000 0.46400000 -0.15842329 1.6604233
#> Study 3 0.4210000 0.10200000 0.22108367 0.6209163
#> Study 4 0.2870000 0.59200000 -0.87329868 1.4472987
#> Study 5 0.0520000 0.86400000 -1.64140888 1.7454089
#> Study 6 0.1460000 0.24100000 -0.32635132 0.6183513
#> Study 7 0.5620000 0.25200000 0.06808908 1.0559109
#> Study 8 0.9040000 0.31800000 0.28073145 1.5272685
# Should return:
# Estimate SE LL UL
# Average 0.3127916 0.06854394 0.17844794 0.4471352
# Study 1 0.0220000 0.12400000 -0.22103553 0.2650355
# Study 2 0.7510000 0.46400000 -0.15842329 1.6604233
# Study 3 0.4210000 0.10200000 0.22108367 0.6209163
# Study 4 0.2870000 0.59200000 -0.87329868 1.4472987
# Study 5 0.0520000 0.86400000 -1.64140888 1.7454089
# Study 6 0.1460000 0.24100000 -0.32635132 0.6183513
# Study 7 0.5620000 0.25200000 0.06808908 1.0559109
# Study 8 0.9040000 0.31800000 0.28073145 1.5272685