Dear all, I have developed regression models using stepAIC() but since the aim of my study is to show the relative importance of different parameters I want the standardised partial regression coefficients, their standard deviations and confidence intervals. The models are based on data from binomial or Poisson distributions. Can I get those estimates from R or do I have to rerun the analysis using normalised data? If the estimates are not available in R I plan to normalise by subtracting each value from the mean of that variable, thereafter dividing with the standard deviation of that variable. I assume there is no problem in normalising binary independent variables. I plan to present each model (the linear component) in a histogram where the height and direction of the bars show the standardised coefficients and their sign, respectively. Error bars will show the 95%-confidence interval. I also would like to know what value is normally presented for summarising fit when the modelling is based on AIC. Is it model AIC or is it mean deviance? In ecological literature I have seen "% explained deviance" assuming it is (Null Dev. - Resid. Dev.) / Null Dev. but I am not really satisfied with this. I am using R 1.1.0 on Windows NT. Thanks in advance for any comments or help! Sincerely, Tord Sn?ll ----------------------------------------------------------------------- ******New e-mail address: Tord.Snall at ebc.uu.se******* Tord Sn?ll, PhD student Avd. f v?xtekologi, Evolutionsbiologiskt centrum, Uppsala universitet Dept. of Plant Ecology, Evolutionary Biology Centre, Uppsala University Villav?gen 14 SE-752 36 Uppsala, Sweden Tel: 018-471 28 82 (int +46 18 471 28 82) (work) Tel: 018-25 71 33 (int +46 18 25 71 33) (home) Fax: 018-55 34 19 (int +46 18 55 34 19) (work) E-mail: Tord.Snall at ebc.uu.se Homepage: http://www.vaxtbio.uu.se/resfold/tord_s.htm ------------------------------------------------------------------------ -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-help mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html Send "info", "help", or "[un]subscribe" (in the "body", not the subject !) To: r-help-request at stat.math.ethz.ch _._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._