Dear R-users, After running a logistic regression, I need to calculate OR by exponentiating the coefficient, and then I need the 95% CL for the OR as well. For the following example (taken from P. Dalaagard's book), what would be the most straightforward method of getting what I need? Could anyone enlight me please? Thank you! Lucho> summary(glm(menarche~age,binomial))Call: glm(formula = menarche ~ age, family = binomial) Deviance Residuals: Min 1Q Median 3Q Max -4.68654 -0.13049 -0.01067 0.09608 2.35254 Coefficients: Estimate Std. Error z value Pr(>|z|) (Intercept) -17.9175 1.7074 -10.49 <2e-16 *** age 1.3549 0.1296 10.45 <2e-16 *** --- Signif. codes: 0 ?***? 0.001 ?**? 0.01 ?*? 0.05 ?.? 0.1 ? ? 1 (Dispersion parameter for binomial family taken to be 1) Null deviance: 974.31 on 703 degrees of freedom Residual deviance: 223.95 on 702 degrees of freedom (635 observations deleted due to missingness) AIC: 227.95 Number of Fisher Scoring iterations: 9
Dear Luciano, See ?logistic.display in the epicalc package. If glm1 is your model, something like logistic.display(glm1) should do the job. HTH, Jorge On Mon, Sep 22, 2008 at 5:28 PM, Luciano La Sala <luciano_la_sala@yahoo.com>wrote:> Dear R-users, > > After running a logistic regression, I need to calculate OR by > exponentiating the coefficient, and then I need the 95% CL for the OR as > well. For the following example (taken from P. Dalaagard's book), what would > be the most straightforward method of getting what I need? Could anyone > enlight me please? > > Thank you! > Lucho > > > summary(glm(menarche~age,binomial)) > > Call: > glm(formula = menarche ~ age, family = binomial) > > Deviance Residuals: > Min 1Q Median 3Q Max > -4.68654 -0.13049 -0.01067 0.09608 2.35254 > > Coefficients: > Estimate Std. Error z value Pr(>|z|) > (Intercept) -17.9175 1.7074 -10.49 <2e-16 *** > age 1.3549 0.1296 10.45 <2e-16 *** > --- > Signif. codes: 0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1 > > (Dispersion parameter for binomial family taken to be 1) > > Null deviance: 974.31 on 703 degrees of freedom > Residual deviance: 223.95 on 702 degrees of freedom > (635 observations deleted due to missingness) > AIC: 227.95 > > Number of Fisher Scoring iterations: 9 > > > > > > > ______________________________________________ > R-help@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide > http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. >[[alternative HTML version deleted]]
l.mod<-glm(menarche~age,binomial) you will get odds-ratios by exponentiating the coefficients of this model, so exp(coef(l.mod)) will do this job. You may notice that this will produce an "OR" for the intercept part as well - which is not interpretable. For the confidence intervals for this odds ratio you have to exponentiate the borders of the "standard" confidence intervals for the log-odds-ratios, exp(confint(l.mod)) hth. Luciano La Sala schrieb:> Dear R-users, > > After running a logistic regression, I need to calculate OR by exponentiating the coefficient, and then I need the 95% CL for the OR as well. For the following example (taken from P. Dalaagard's book), what would be the most straightforward method of getting what I need? Could anyone enlight me please? > > Thank you! > Lucho > > >> summary(glm(menarche~age,binomial)) >> > > Call: > glm(formula = menarche ~ age, family = binomial) > > Deviance Residuals: > Min 1Q Median 3Q Max > -4.68654 -0.13049 -0.01067 0.09608 2.35254 > > Coefficients: > Estimate Std. Error z value Pr(>|z|) > (Intercept) -17.9175 1.7074 -10.49 <2e-16 *** > age 1.3549 0.1296 10.45 <2e-16 *** > --- > Signif. codes: 0 ?***? 0.001 ?**? 0.01 ?*? 0.05 ?.? 0.1 ? ? 1 > > (Dispersion parameter for binomial family taken to be 1) > > Null deviance: 974.31 on 703 degrees of freedom > Residual deviance: 223.95 on 702 degrees of freedom > (635 observations deleted due to missingness) > AIC: 227.95 > > Number of Fisher Scoring iterations: 9 > > > > > > > ______________________________________________ > R-help at r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. >-- Eik Vettorazzi Institut f?r Medizinische Biometrie und Epidemiologie Universit?tsklinikum Hamburg-Eppendorf Martinistr. 52 20246 Hamburg T ++49/40/42803-8243 F ++49/40/42803-7790