Discussion Paper
No. 2008-10 | April 03, 2008
Benoît Mercereau and Jacques Miniane
Should We Trust the Empirical Evidence from Present Value Models of the Current Account?

Abstract

The present value model of the current account has been very popular, as it provides an optimal benchmark to which actual current account series have often been compared. We show why persistence in observed current account data makes the estimated optimal series very sensitive to small-sample estimation error, making it close to impossible to determine whether the paths of the two series truly bear any relation to each other. Moreover, the standard Wald test of the model will falsely accept or reject the model with substantial probability. Monte Carlo simulations and estimations using annual and quarterly data from five OECD countries strongly support our predictions. In particular, we conclude that two important consensus results in the literature – that the optimal series is highly correlated with the actual series, but substantially less volatile – are not statistically robust. Paper submitted to the special issue "Using Econometrics for Assessing Economic Models" edited by Katarina Juselius.

Data Set

JEL Classification:

C11, C52, F32, F41

Links

Cite As

[Please cite the corresponding journal article] Benoît Mercereau and Jacques Miniane (2008). Should We Trust the Empirical Evidence from Present Value Models of the Current Account? Economics Discussion Papers, No 2008-10, Kiel Institute for the World Economy. http://www.economics-ejournal.org/economics/discussionpapers/2008-10


Comments and Questions



Sunil Sapra - Comments on "Should We Trust the Empirical Evidence from Present Value Models of the Current Account?" by Benoît Mercereau and Jacques Miniane
April 12, 2008 - 09:20
1. The performance of nonlinear Wald tests in small samples may be improved upon by using bootstrap tests. 2. The following drawback of nonlinear Wald test has been noted by Gregory and Veall (Econometrica, 1985). Changing the form of the nonlinear restriction to an algebraically equivalent form under the null hypothesis changes the numerical value of the Wald test statistic and hence there can be conflicts among different Wald tests. Likelihood ratio and Lagrange Multiplier tests do not suffer from this problem and are therefore preferred.

Jacques Miniane - response to Sunil's comments
April 15, 2008 - 21:46
Sunil, Thank you for your comments. As you note, there have been previous criticisms of the non-linear Wald test, some of which (but not all of which) we quote in the paper. Remember that our point in the paper is not so much to add to the general/theoretical criticisms of the non-linear Wald test, but rather to show how the shortcomings of the test apply in this particular literature of present value models of the current account, and how these shortcomings "invalidate" some of the results in this literature. Related to this, we show why the non-linear Wald fails in this particular literature (current account persistence) and show how alternative tests (which we never claim to be "ours") do much better in this particular literature. We believe none of these issues had been signalled before in this particular (but important) literature of intertemporal current accounts. You could say that the problem is that this literature has relied too much on a test which other literatures have shown to be problematic in short samples. Beyond the issues of the Wald, we believe a key (perhaps the key) contribution of our paper is showing the huge small sample uncertainty surrounding estimates of optimal current accounts. In the end, we believe the reason the model has been so popular is because of its supposed ability to generate optimal series which can be compared with the actual. As we show, these comparisons are much less useful than people have made them to be. Thanks for your comments

Anonymous - Referee Report
April 28, 2008 - 11:31
see attached file

Jacques Miniane - Response to the referee report
May 27, 2008 - 23:08
Here's our full response to the referee report #1

Jacques Miniane - Addendum to our response
June 11, 2008 - 00:21
This addendum corrects a simulation contained in our response to the first referee report.

Anonymous - Referee Report
May 21, 2008 - 11:19
see attached file

Jacques Miniane - Response to referee report #2
June 11, 2008 - 00:22
Here's our full response.

Katarina Juselius - Editor`s Report
July 04, 2008 - 08:37
see sttached file

Hafedh Bouakez - Related paper
September 18, 2008 - 04:38 | Author's Homepage
Attached is a short note (forthcoming in Applied Economics Letters) that is related to Benoit and Jacques' paper.

Jacques Miniane - Respond to Hafedh Bouakez
October 16, 2008 - 09:17
Hafedh, thanks for pointing us to your paper, which is highly relevant to and complementary with ours. In particular, it's good to note that both papers find similar results with UK quarterly data. We have resubmitted a revised version of our paper and the new version cites your paper and discusses your results. Thanks, Jacques