Why PPML results gone wrong.... Please help
I am running regression to calculate gravity model
Dependent variable= log exports in (OLS, Tobit) Level Eports in mn US$ (PPML)
Independent variable= GDP-i, GDP-j, Distance-ij, Abs-difrential-pcgdp-ij, population-j, weighted distance-ij, Dummies (border, religion, language, regional agreements, landlocks, WTO)
Expected negative results= Distance-ij, Weighted Distance-ij, landlocks
**OLS resutls**
[ATTACH=CONFIG]n1396639[/ATTACH]
**Tobit Results**
[ATTACH=CONFIG]n1396640[/ATTACH]
**PPML resutls**
[ATTACH=CONFIG]n1396641[/ATTACH]
why most of the variable gone negative. Please assist me
Regards
Saqib
Dependent variable= log exports in (OLS, Tobit) Level Eports in mn US$ (PPML)
Independent variable= GDP-i, GDP-j, Distance-ij, Abs-difrential-pcgdp-ij, population-j, weighted distance-ij, Dummies (border, religion, language, regional agreements, landlocks, WTO)
Expected negative results= Distance-ij, Weighted Distance-ij, landlocks
**OLS resutls**
[ATTACH=CONFIG]n1396639[/ATTACH]
**Tobit Results**
[ATTACH=CONFIG]n1396640[/ATTACH]
**PPML resutls**
[ATTACH=CONFIG]n1396641[/ATTACH]
why most of the variable gone negative. Please assist me
Regards
Saqib
