This chapter discusses three theories related to inflation, interest rates, and exchange rates:
1) Purchasing power parity (PPP) theory suggests that inflation differentials between countries will be offset by exchange rate changes.
2) International Fisher effect (IFE) theory suggests that higher interest rates in a country reflect higher expected inflation, so the currency of that country will depreciate.
3) Tests of these theories show they do not always hold perfectly due to other factors affecting exchange rates. However, PPP and IFE provide useful frameworks for understanding long-run relationships between macroeconomic variables.