Baltagi paper on testing for heteroskedasticity published in Journal of Econometrics
Jan 31, 2020
Badi H.Baltagi, Byoung Cheol Jung & Seuck HeunSong
Journal of Econometrics, January 2010
Badi H. Baltagi
This paper considers a panel data regression model with heteroskedastic as well as serially correlated disturbances, and derives a joint LM test for homoskedasticity and no first order serial correlation. The restricted model is the standard random individual error component model. It also derives a conditional LM test for homoskedasticity given serial correlation, as well as, a conditional LM test for no first order serial correlation given heteroskedasticity, all in the context of a random effects panel data model. Monte Carlo results show that these tests along with their likelihood ratio alternatives have good size and power under various forms of heteroskedasticity including exponential and quadratic functional forms.