effect sizes

Effect sizes used in meta-analysis of sex ratio adjustment in response to a lack of helpers in cooperatively breeding birds. Test statistics used to calculate effect size are provided, except where these were taken directly from a previous publication (detailed in technique column). Magnitude of effect given in effect_size; effect_exp includes positive/negative direction relative to prediction (biased production of helpful sex in response to deficiency of help). Variance is given in v and used to calculate weight (1/v) for calculation of weighted mean. Columns containing max and/or min are the same as for effect_exp but with the effect sizes of unknown direction treated as positive or negative respectively. Overall weighted mean and confidence interval reported in the manuscript.