Do Panels Help Solve the Purchasing Power Parity Puzzle?
用面板中位数无偏估计方法重新检验购买力平价偏离的半衰期，发现面板方法虽比单变量回归提供更多信息，但并未解决PPP之谜，仍支持Rogoff的3-5年半衰期结论。
AbstractAlthough Rogoff described the "remarkable consensus" of 3- to 5-year half-lives of purchasing power parity (PPP) deviations among studies using long-horizon data, recent works using panel methods with post-1973 data report shorter half-lives of 2 to 2.5 years. But these studies do not use appropriate techniques to measure persistence. We extend median-unbiased estimation methods to the panel context, calculate both point estimates and confidence intervals, and provide strong evidence confirming Rogoff's original claim. Although panel regressions provide more information on the persistence of real exchange rate shocks than univariate regressions, they do not help solve the PPP puzzle.KEY WORDS: Panel median-unbiased estimationPPP puzzleReal exchange rate persistence