I had a few questions about homework 6.
1. When we are doing the fitted values for part (a), what values do we use
for PRESINC? Is PRESINC = 1 mean an incumbent candidate is running, and
PRESINC = 0 mean incumenbent candidate is not running? I noticed that
there are some entries with "-1" values also - what is that value?
My guess is that 1 is the democratic incumbent, 0 is no incumbent, and -1
is republican incumbent.
2. For each of the scenarios, it seems like we
don't need the ADAACA
value.
you can set that variable to its mean, for example.
Also, in the first paragraph of the assignment sheet,
it says
"the interaction term of PRESINC and JULYECQ2 as covariates". Does this
mean that we run the glm with probit for just the PRESINC and JULYECQ2
(without ADAACA) as the covariates and use the resulting coefficients
for the fitted values?
you want the interaction term in addition to the other terms.
3. For the different scenarios in calculating the
fitted values, what
varible do we use to indicate that a "Democratic candidate" is running?
PRESINC, I think.
Kosuke