Fact · Speech recognition
100percent
Word error rate can be greater than 100 percent, because its equation counts insertions as errors.
Checked against its source on October 17, 2026
In the source's own words
“note that because the equation includes insertions, the error rate can be greater than 100%”
Speech and Language Processing, Chapter 16: Automatic Speech Recognition (draft), Daniel Jurafsky and James H. Martin, Stanford University, online manuscript of the third edition, 2026, Chapter 16, automatic speech recognition.
Open the original- What it measures
- The third-edition draft of Jurafsky and Martin's textbook, chapter 16 on automatic speech recognition.
- What it does not show
- The bound applies to the standard formula. Some other error measures are normalized differently.