The IMF Working Papers series is designed to make IMF staff research available to a wide audience. Almost 300 Working Papers are released each year, covering a wide range of theoretical and analytical topics, including balance of payments, monetary and fiscal issues, global liquidity, and national and international economic developments.
Under near-singularity conditions typically generated by persistence in current account data the predictions of present value models become extremely sensitive to small sample estimation error. Moreover, traditional Wald tests will distort the likelihood that the model is true. Using OECD data we find that: (i) the Wald test often leads to the wrong inference compared to a valid test; (ii) in all cases posterior distributions of the predicted series and associated correlation coefficients and variance ratios are very wide. In particular, one cannot draw any firm conclusion regarding excess current account volatility.