3.2 Logistic model

Examine the bivariate relationship first among variables to high protein status of milk. Check for quasi or complete separation of categories. Shout out to Lisa Avery for this function!

plotuv(data=Milk, response='High_Protein', covs=c('Cow', 'Yard', 'Diet', 'Time', 'protein'));

Below logistic model does not account for clustering of repeat observations by cow to high protein status of milk.

rm_mvsum(model=glm(High_Protein ~ Diet + Yard + Time, data=Milk, family='binomial'), showN=T, vif=T);
OR(95%CI) p-value N Event VIF
Diet 1337 386 1.02
barley Reference 425 183
barley+lupins 0.45 (0.34, 0.60) <0.001 459 119
lupins 0.29 (0.21, 0.40) <0.001 453 84
Yard 1337 386 1.01
1 Reference 251 66
2 1.29 (0.86, 1.92) 0.21 276 76
3 1.71 (1.16, 2.53) 0.007 272 92
4 1.31 (0.89, 1.95) 0.17 268 87
5 1.08 (0.72, 1.63) 0.70 270 65
Time 0.98 (0.95, 1.00) 0.044 1337 386 1.00