How can you estimate non-linear function forms using least squares?
a.) estimate the linear approximation over small ranges at a time
b.) transform, such as squaring or cubing, some explanatory variables.
c.) use a very large sample so you do not have to assume the error terms are normally
distributed
d.) It cannot be done. You need to use another estimation technique.
How are logit and probit models different?
a.) probit is estimated by least squares, logit by maximum likelihood
b.) probit uses the cumulative density function (cdf) of the standard normal distribution
and logit uses the cdf of the logistic function
c.) logit is for binary choice models and probit is used when there are two or more
choices
d.) probit allows for endogenous regressors, logit does not
When should a Heckit model be used?
a.) when the sample was not randomly selected
b.) when the sample is small and error terms are not normally distributed
c.) as the alternative model to run a Hausman test on a Tobit model