Question

Observation motheduc bwght 2,778 3,600 3,374 1,219 2,835 faminc 37.5 15.5 42.5 22.5 22.5 3 bwght = the infant's birth weight in grams faminc = the family's weekly income in $US thousand dollars motheduc = the mother's education in years Suppose you regress bwght on motheduc using observations 3 and 5 only. What result will you get? Briefly explain why this result occurs.

Answer 1

If you regress using only observations 3 and 5, these are the data:

Observation #	bwght	motheduc
3	3374	12
5	2835	12

Since thiere's no difference in the independent variable between the observations, the coefficient will be 0. So the equation will be something like:

bwght = constant + b.mothereduc, where b is likely to be zero