Dear forum members, Please help me understanding significance value when GLM done in r.
After doing minimal adequate model, I have found a number of independent values which are significant. But doing their anova significant values are different. Please find my result following. Which significant values should I use. glm(formula = richness ~ moistcont + orgmatter + baresoil + grass10 + wood10 + rdnet10 + moistcont:orgmatter + moistcont:baresoil + grass10:wood10 + grass10:rdnet10 + wood10:rdnet10, family = poisson, data = data) Deviance Residuals: Min 1Q Median 3Q Max -1.19112 -0.33682 0.09813 0.32808 0.70509 Coefficients: Estimate Std. Error z value Pr(>|z|) (Intercept) 11.384447 4.014170 2.836 0.00457 ** moistcont -0.095813 0.084995 -1.127 0.25962 orgmatter -1.810116 0.613688 -2.950 0.00318 ** baresoil -1.636707 0.559129 -2.927 0.00342 ** grass10 -0.018979 0.065647 -0.289 0.77250 wood10 0.150683 0.128386 1.174 0.24053 rdnet10 -0.011448 0.068090 -0.168 0.86648 moistcont:orgmatter 0.025698 0.011521 2.231 0.02571 * moistcont:baresoil 0.044110 0.015799 2.792 0.00524 ** grass10:wood10 0.010740 0.006498 1.653 0.09838 . grass10:rdnet10 0.011013 0.004412 2.496 0.01255 * wood10:rdnet10 -0.088297 0.027120 -3.256 0.00113 ** --- Signif. codes: 0 *** 0.001 ** 0.01 * 0.05 . 0.1 1 (Dispersion parameter for poisson family taken to be 1) Null deviance: 36.1673 on 17 degrees of freedom Residual deviance: 3.9276 on 6 degrees of freedom AIC: 97.893 Number of Fisher Scoring iterations: 4 > anova(data1, test="Chisq") Analysis of Deviance Table Model: poisson, link: log Response: richness Terms added sequentially (first to last) Df Deviance Resid. Df Resid. Dev Pr(>Chi) NULL 17 36.167 moistcont 1 8.6322 16 27.535 0.003303 ** orgmatter 1 2.1244 15 25.411 0.144966 baresoil 1 0.0029 14 25.408 0.956986 grass10 1 1.5251 13 23.883 0.216842 wood10 1 3.6952 12 20.187 0.054570 . rdnet10 1 0.0001 11 20.187 0.990564 moistcont:orgmatter 1 2.0482 10 18.139 0.152381 moistcont:baresoil 1 2.8730 9 15.266 0.090076 . grass10:wood10 1 0.1431 8 15.123 0.705247 grass10:rdnet10 1 0.4141 7 14.709 0.519883 wood10:rdnet10 1 10.7812 6 3.928 0.001025 ** --- Signif. codes: 0 *** 0.001 ** 0.01 * 0.05 . 0.1 1 [[alternative HTML version deleted]]
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