Update FinalProj.Rmd

FinalProj.Rmd

 ---
 title: "finalproj403"
-author: "Iris Lin and Hannah Zhou"
+author: "irisqlin"
 date: "11/13/2021"
 output: html_document
 ---
@@ -278,10 +278,45 @@ anova(cig_mod_3, cig_mod_2, test="Chisq")
 anova(cig_mod_3, cig_mod_1, test="Chisq")
 # The difference in deviance is significantly significant, the drop in dev test prefers the smaller model, mod 3
 
+summary(cig_mod_3)
+
+exp(coef(cig_mod_3))
+
+```
+
+## Marijuana model
+
+```{r}
+# making models, 1 = abusing substance, 0 = not abusing substance
+mar_threshold <- mean(data$X30marijuana)
+data$mar_var <- ifelse(data$X30marijuana >= mar_threshold, 1, 0)
+
+# total model
+mar_total_mod <- glm(mar_var ~ pride + truth + responsibility + friends + fix.problems + decision + excite + hard.work + safe + best.school + talk.adult + grades + Wpdrink + N.safe, data = data, family = "binomial")
+summary(mar_total_mod)
+
+# dropped by p > 0.1
+mar_mod_1 <- glm(mar_var ~ truth + decision + excite + best.school + grades + Wpdrink, data = data, family = "binomial")
+summary(mar_mod_1)
+
+#likelihood ratio test to test whether the observed difference in model fits is statistically significant
+# source: https://www.listendata.com/2016/07/insignificant-levels-of-categorical-variable.html
+anova(mar_mod_1, mar_total_mod, test="LRT")
+# not sig, prefer smaller model mod 1
+
+# Drop in deviance test
+anova(mar_mod_1, mar_total_mod, test="Chisq")
+# not sig, essentially no difference in residual deviance values
+
+summary(mar_mod_1)
+
+exp(coef(mar_mod_1))
+
 ```
 
 
 
+
 ```{r}
 # Extra code
 fiveDrinks_mod_3 <- glm(fiveDrinks_var ~ Wpdrink + friends, data = data, family = "binomial")