Several different approaches have been followed by researchers to test the validity of Purchasing Power Parity (PPP). Since the introduction of the unit-root tests, researchers have applied a battery of these tests to determine whether the real exchange rates are stationary. If the answer is in...

Devaluation or depreciation of a currency worsens the trade balance before improving it, resulting in a J-curve pattern. A new definition of the hypothesis implies a short-run deterioration combined with the long-run improvement. By using monthly data over the January 1990-June 2005 period from...