Meta-analysis on effects of elevated CO_2 on total biomass of woody plants
A data frame with the following columns:
Database paper number
Number of observations in experimental group (elevated CO_2-level)
Estimated mean in experimental group
Standard deviation in experimental group
Number of observations in control group (ambient CO_2-level)
Estimated mean in control group
Standard deviation in control group
This dataset has been used as an example in Hedges et al. (1999) to describe methods for the meta-analysis of response ratios. The complete dataset with 102 observations and 26 variables is available online as a supplement. Here only a subset of 10 variables is provided and used in the examples.
Hedges LV, Gurevitch J, Curtis PS (1999), The meta-analysis of response ratios in experimental ecology. Ecology, 80, 1150–6.
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data(woodyplants) # Meta-analysis of response ratios (Hedges et al., 1999) # meta8 <- metacont(n.elev, mean.elev, sd.elev, n.amb, mean.amb, sd.amb, data=woodyplants, sm="ROM", studlab=paste(obsno, papno, sep = " / ")) summary(meta8, prediction=TRUE) # Meta-analysis for plants grown with low soil fertility treatment # meta9 <- update(meta8, subset=(treat=="fert"&level=="low")) summary(meta9, prediction=TRUE) # Meta-analysis for plants grown under low light conditions # meta10 <- update(meta8, subset=(treat=="light"&level=="low")) summary(meta10, prediction=TRUE)