6.13
The Fisher Effect, proposed by economist Irving Fisher, explains how expected inflation affects nominal interest rates. It shows that the nominal rate—measured in the loanable funds market—reflects both inflation expectations and the desired real rate of return on investments, or the real interest rate.
The relationship is expressed through the equation, Nominal Interest Rate = Real Interest Rate + Expected Inflation, written as: i = r + π.
Consider John, an investor aiming for a real return of 2%—a return above inflation. If inflation is expected to be 6%, earning just 2% isn’t enough, as rising prices would erode his earnings. To protect his purchasing power, John needs a nominal interest rate of 8%—that is, 2% plus 6%. This ensures he still gains 2% in real terms after adjusting for inflation.
The Fisher Equation explains how expected inflation raises nominal interest rates, helping investors like John preserve the real value of their earnings.
The Fisher Effect helps us understand why interest rates often rise when people expect inflation. It tells us that the nominal interest rate (the one…
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