Lab 8 Assignment

For this assignment you will be using the data infert.csv. This data is from a case control study on infertility following spontaneous and induced abortions. We're not going to worry about infertility. Instead the goal today is to predict the number of spontaneous abortions from age and education levels. The variable spontaneous has 3 levels (0=0 abortions, 1=1 abortion, 2=2 or more abortions).

1. Fit a multicategory logistic regression with age and education predicting spontaneous abortions. What is the effect of age? What is the effect of education? Are either of these effects significant? (use the Wald or LR tests and justify your choice).

2. Fit an ordinal (cumulative) logistic regression with age and education predicting spontaneous abortions. What is the effect of age? What is the effect of education? Are either of these effects significant? (use the Wald or LR tests and justify your choice)

3. Which model (multicategory or ordinal logistic) is a better choice with this data? Why?