On Sat, March 4, 2006 07:58, Al Leong wrote:
It may be useful to incorporate some of the
modules/features available under Grocer (see below)
that are not currently available, e.g. three-stage
least square, pc-gets like device that performs
automatic general to specific estimations:
Grocer is the econometric toolbox developed for
Scilab, a matrix-oriented software similar to Gauss
and Matlab. Like Scilab, Grocer is free and open
source.
http://dubois.ensae.net/grocer.html
Thank you, I didn't know about grocer. I'll have a look when I have time (not
today!!!). However, it seems that the list of things we could take from grocer
is not so big after all. From the project web page:
- ordinary least squares and various single equation methods (autocorelated
models, instrumental variables, non linear least squares, limited dependent
variables, robust methods,...)
we've got all of these
- specification tests (multicolinearity, autocorelation, heteroskedasticity,
normality, predictive failure,...)
ditto
- simultaneous equations methods (SUR, two and three stage least squares,...)
ditto, plus liml and fiml
- VAR, VECM, VARMA and GARCH estimation
VECM needs some more love, but that's on the todo list. We haven't got varma.
However, you'll agree that VARMAs are not the most widely used models in
econometrics :-) Still, Allin has recently committed code that provides the
foundation for VARMA estimation should we decide we need it.
- the Kalman filter and time varying parameters estimation
see VARMA
- unit root tests (ADF, KPSS,...) and cointegration methods (CADF, Johansen,...)
we've got these too
- various business cycle tools: HP, Baxter-King and Christiano-Fitzgerald
filters, the Bry-Boschan-Harding-Pagan procedure for the datation of turning
points, spectral analysis
We've haven't got Christiano-Fitzgerald, which is a simple modification to
Baxter-King and should be easy to do if we need it. I don't know what the
Bry-Boschan-Harding-Pagan procedure is, I'll take a look at it. The spectral
analysis tools we have as of now are functional if a bit basic; again, we may
want to make some progress here (eg. cross-spectra)
- basic panel data estimation: fixed and random effects, between estimation
We've got these. More to come in the future.
- numerous time series disaggregation methods: Chow-Lin, Litterman,...
None of these, but they should be easy to "script out".
# some rare -and useful- ones:
- a pc-gets like device, that performs automatic general to specific estimations
Personally, I'd rather avoid this. With all due respect for David Hendry &
co., I'm a little wary of the magic machine where you put data in and the
"right" model miraculously comes out. But maybe it's just me becoming an
old
fart with age.
- a contributions device, that provides contributions of exogenous variables
to an endogenous one for any dynamic equation
What's this?
--
Riccardo "Jack" Lucchetti
Dipartimento di Economia
FacoltĂ di Economia "G. FuĂ "
Ancona