class15-06

# class15-06 - Econ 444 Wednesday November 15 class 15 Econ...

This preview shows pages 1–6. Sign up to view the full content.

Econ 444, Wednesday November 15, class 15 Econ 444, Wednesday November 15, class 15 Robert de Jong 1 1 Department of Economics Ohio State University Robert de Jong Econ 444, Wednesday November 15, class 15

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Econ 444, Wednesday November 15, class 15 Wednesday November 15 1 Exercise of last Wednesday 2 F -tests 3 Heteroskedasticity Robert de Jong Econ 444, Wednesday November 15, class 15
Econ 444, Wednesday November 15, class 15 Exercise 1. coefficient = -901; standard error = 540; so coefficient is 901/540=1.67 standard errors away from zero Conclusion: do not reject the null that the coefficient is zero 2. The long regression - that is, if we are interested in the existence of wage discrimination instead of in the existence of wage differences between men and women 3. West: 341/562 = 0.61 East: 344/668 = 0.51 South: 861/659 = 1.31 Conclusion: we cannot reject the null that the coefficient equals zero in any case Robert de Jong Econ 444, Wednesday November 15, class 15

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Econ 444, Wednesday November 15, class 15 4. F -test tests for the hypothesis that the coefficients for west, east and south are all zero at the same time We test for such a hypothesis using an F -test Here: the F -test rejects, but no t -test rejects: conflicting statistical evidence This is fairly arbitrary but: 1. leaving out a variable can make regression results erroneous 2. including irrelevant variables will not hurt us suggestion: leave the regional dummy variables in! Robert de Jong Econ 444, Wednesday November 15, class 15
Econ 444, Wednesday November 15, class 15 F -test: tests a so-called “multiple hypothesis" Examples: 1 β 1 = β 2 = β 3 = 0 (three regional dummies) 2 β 1 = β 2

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### Page1 / 15

class15-06 - Econ 444 Wednesday November 15 class 15 Econ...

This preview shows document pages 1 - 6. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online