‘Modelling non-stationary economic time series’
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Transcript of ‘Modelling non-stationary economic time series’
www.elsevier.com/locate/ijforecast
International Journal of For
Book review
Simon P. Burke & John Hunter, Modelling non-
stationary economic time series: A multivariate
approach, Palgrave texts in Econometrics, Mac-
millan, 2005, ISBN: 1-4039-0202-X (cloth) or 1-
4039-0203-8 (pbk), 253 pp., £19.99
Along with many others, I have always found it
difficult to construct multivariate models for time series
data. The seminal paper by Box and Newbold (1971)
showed that even eminent statisticians like Sir Maurice
Kendall could be fooled by spuriously large cross-
correlations contaminated by autocorrelations within
the individual series. I am also aware that statisticians
and economists have often worked with little knowl-
edge of what each other is doing (with occasional
exceptions such as Clive Granger). This is a book
written by economists for economists and so it is not
obvious that a statistician like me should be reviewing
it. Yet, it is only by cross-fertilization that barriers can
be broken down. As I rather expected, this book refers
to much econometric research that is unfamiliar to me. I
also notice the absence of references to statistical work
that I would regard as fundamental (e.g. Reinsel’s
(1997) book and the work of George Tiao and Ruey
Tsay, the latter represented by just one joint paper). The
book concentrates on the search for co-integration and
for exogeneity, often guided by economic theory. VAR
and VARMA models are employed but there is no
mention of statistical tools such as the cross-correlation
function and the cross-spectrum. Readers of this
journal will want to know that there is rather little
emphasis explicitly on forecasting, apart from Section
6.3 on forecasting cointegrated systems. They should
also be aware that there is no reference whatsoever to
research that has appeared in the Journal of Forecasting
or the International Journal of Forecasting. There are no
examples that take the reader right through from the
initial examination of real multivariate data through the
doi:10.1016/j.ijforecast.2005.12.003
modelling process and onto forecasting, but rather the
examples use data published elsewhere to illustrate
particular tests or procedures. One bivariate simulated
sample in Chapter 3 is used to illustrate cointegration.
The text has not changed my view that multivariate
modelling is hard!
I was also somewhat disturbed by apparent flaws in
the text that hinder understanding. For example
(concentrating on Chapter 2, Univariate Time Series),
I spotted non-trivial typos in equations (2.9b), (2.9c),
(2.11a), (2.24), the sentence after (2.10b), the expan-
sion of Dd on page 31, and in the legends for Fig. 2.1
(surely T=124) and 2.4. More generally, the graphics
software used in the book generally labels scales in
rather peculiar ways, and the drawing in Fig. 2.7
appears to have been erroneously copied from Fig.
2.6, albeit with a different legend. As regards the text,
I found it difficult to follow in places and I was
particularly concerned to read on page 17 that, for an
MA(2) process, dthe autocovariances depend not only
on the time gap, but on the time itself. The process is
therefore stationary. . ..T!! No doubt these are all slips
of the pen that can be corrected in any later printings,
but they make it difficult to recommend the book in its
present form.
References
Box, G.E.P., & Newbold, P. (1971). Some comments on a paper of
Coen, Gomme and Kendall. Journal of the Royal Statistical
Society, Series A, 134, 229–240.
Reinsel, G. C. (1997). Elements of multivariate time series analysis
(2nd edn.). New York7 Springer-Verlag.
Chris Chatfield
Department of Mathematical Sciences,
University of Bath, Bath, BA2 7AY, United Kingdom
E-mai l address: c [email protected] h.ac.uk.
ecasting 22 (2006) 819