CLEVELAND — Janet L. Yellen, the Federal Reserve chairwoman, said on Tuesday that the Fed plans to keep raising its benchmark interest rate despite the mysterious weakness of inflation.

Ms. Yellen said that increasing competition for workers was driving up wages, and inflation was likely to follow. She said that the Fed could raise rates more slowly if it concluded that its inflation expectations needed to be revised but that the central bank was not yet ready to recalibrate.

“Given that monetary policy affects economic activity and inflation with a substantial lag, it would be imprudent to keep monetary policy on hold until inflation is back to 2 percent,” Ms. Yellen told the National Association for Business Economics here.

The Fed has raised its benchmark rate twice this year, to a range between 1 and 1.25 percent. Investors expect the Fed to raise the benchmark rate for a third time at its final meeting of the year, in mid-December. The Fed kept rates unusually low for years after the 2008 financial crisis to encourage borrowing and risk-taking; it is gradually raising rates to reduce that stimulus as the economy recovers.