1. See the data below describing three different birth production functions. The three columns to the right represent three different dependent variables with birth weight as a continuous function (in grams), a dummy variable for whether the baby was born low birth weight or not, and whether the baby was born with an abnormal condition. The first column is the independent variables. The data come from a published article in the link below. Use the data to answer the following questions about "producing" healthy babies.

Variable	Birth Weight in Grams	Low Birth Weight (Y/N)	Abnormal Condition (Y/N)
Prenatal illicit drug use	139.26**	0.04**	0.06***
Prenatal cigarette smoking	173.56***	0.05***	0.00
First trimester prenatal care	17.61	0.00	0.01
Considered abortion	23.35	0.00	0.02
STD during pregnancy	2.81	0.02	0.03***
Pre-existing lung disease	27.31	0.03**	0.01
Other pre-existing health condition	45.43	0.04**	0.01
Pre-pregnancy underweight	108.67**	0.04	0.04
Pre-pregnancy morbidly obese	64.47	0.01	0.03
History of mental illness	28.54	0.04**	0.01
Mean	3221	0.10	0.12
N	3122	3124	3101

*** (P<0.01)

** (P<0.05)

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2697267/

1. Interpret the coefficients on drug use and smoking for the first column of estimates (birth weight in grams). What exactly do they mean?
2. Interpret the coefficient "history of mental illness" for the second column (low birth weight). Hint: this is a dummy variable that takes on the value 1 if the baby was born low birth weight and 0 otherwise.
3. Looking at the variable for first trimester pre-natal care, why do you think it lacks statistical significance?
4. Interpret the coefficient on STD during pregnancy on the third column (Abnormal Condition - also a dummy variable with a 0 for no abnormality and 1 for abnormality).
5. Based on the information in the table, discuss the contribution of medical care and other lifestyle issues to the production of healthy babies. In particular, what types of interventions would you consider promoting to reduce the incidence of pre-term low birth weight babies?