Monday, April 21, 2014

More On the Limitations of the Jarque-Bera Test

Testing the validity of the assumption, that the errors in a regression model are normally distributed, is a standard pastime in econometrics. We use this assumption when we construct standard confidence intervals  for, or test hypotheses about, the parameters of our models. In a post some time ago I pointed out that this assumption is actually is sufficient, but not necessary, for the validity of these inferences.

More recently, here and here, I discussed some aspects of the normality test that most econometricians use - the asymptotically valid test of Jarque and Bera (1987). Let's refer to this as the JB test. In the first of those posts I made brief mention of the finite-sample properties of the JB test, and I concluded:
"However, more recent evidence suggests that the power of the J-B test can be quite low in small samples, for a number of important alternative hypotheses - e.g., see Thadewald and Buning (2004). I'll address this aspect of the J-B test more fully in a later post."
The main results obtained by Thadewald and Buning are summed up in the abstract to their paper .............

Ray Fair's Model(s) in EViews

Here's a follow-up to my recent post about the Federal Reserve U.S. macroeconometric model being freely available in EViews format

Ray Fair's well-known model for the U.S. economy is also now available in a form that's ready to play with in EViews. See here. This is a great teaching tool, and a terrific resource for econometrics students.

In case you're looking for some special fun, Ray is looking for someone to convert his multi-country (MC) model into EViews format, so that it will also be freely available to all of us. The MC model covers 38 countries, and is described here.

HT to Gareth at IHS EViews for alerting me to these developments.




© 2014, David E. Giles