Voice recognition computers find men harder to understand than women, Edinburgh University scientists have found.
In the study, researchers recorded phone calls and studied how much of conversations a recognition system could understand, and after analysis discovered that computers failed to understand men's speech because they make "umm" and "err" sounds more frequently.
The research also revealed that computers made mistakes with words which sound similar and can occur in similar contexts, such as "I saw him" or "I saw them", the BBC News reported.
Experts said it was hard to design a computer that could understand so many different kinds of voices but this research should help improve it.
The study, a collaboration between the University of Edinburgh and Stanford University in the United States, was published in the journal Speech Communication.
Sharon Goldwater, of Edinburgh University's school of informatics, who led the research, said: "Voices vary from one person to the next and it is challenging to design a computer system that can understand lots of different voices."
"We hope that by closely studying how people speak and how machines process this, we can help create better systems that will be simple and efficient for people to use," added Goldwater.
Researchers carried out the study by recording phone discussions between pairs of people and feeding their conversation into a speech recognition system to see how much it could understand.