THE META-ANALYSIS OF RESPONSE RATIOS IN EXPERIMENTAL ECOLOGY

EcologyVolume 80, Issue 4 p. 1150-1156 Special Feature THE META-ANALYSIS OF RESPONSE RATIOS IN EXPERIMENTAL ECOLOGY Larry V. Hedges, Larry V. Hedges Department of Education, University of Chicago, 5835 South Kimbark Avenue Chicago, Illinois 60637 USASearch for more papers by this authorJessica Gurevitch, Jessica Gurevitch Department of Ecology and Evolution, State University of New York, Stony Brook, New York 11794 USASearch for more papers by this authorPeter S. Curtis, Peter S. Curtis Department of Plant Biology, Ohio State University, 1735 Neil Avenue, Columbus, Ohio 43210 USASearch for more papers by this author Larry V. Hedges, Larry V. Hedges Department of Education, University of Chicago, 5835 South Kimbark Avenue Chicago, Illinois 60637 USASearch for more papers by this authorJessica Gurevitch, Jessica Gurevitch Department of Ecology and Evolution, State University of New York, Stony Brook, New York 11794 USASearch for more papers by this authorPeter S. Curtis, Peter S. Curtis Department of Plant Biology, Ohio State University, 1735 Neil Avenue, Columbus, Ohio 43210 USASearch for more papers by this author First published: 01 June 1999 https://doi.org/10.1890/0012-9658(1999)080[1150:TMAORR]2.0.CO;2Citations: 2,549Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinkedInRedditWechat Abstract Meta-analysis provides formal statistical techniques for summarizing the results of independent experiments and is increasingly being used in ecology. The response ratio (the ratio of mean outcome in the experimental group to that in the control group) and closely related measures of proportionate change are often used as measures of effect magnitude in ecology. Using these metrics for meta-analysis requires knowledge of their statistical properties, but these have not been previously derived. We give the approximate sampling distribution of the log response ratio, discuss why it is a particularly useful metric for many applications in ecology, and demonstrate how to use it in meta-analysis. The meta-analysis of response-ratio data is illustrated using experimental data on the effects of increased atmospheric CO2 on plant biomass responses. Supporting Information Filename Description https://dx.doi.org/10.6084/m9.figshare.c.3297278 Research data pertaining to this article is located at figshare.com: Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. 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