Experiment shows smartphone speech recognition faster than typing

SAN FRANCISCO - Results from an experiment suggest that speech recognition, in case of composing text messages on smartphone, can be faster and more accurately than humans can type on phone screens.

The experiment by researchers from Stanford University, Baidu Inc and the University of Washington brought in 32 texters, ages 19 to 32, to work the built-in keyboard on an Apple iPhone against Baidu's Deep Speech 2 cloud-based speech recognition software.

"They grew up texting, so we're putting speech recognition up against people who are really good at this task," James Landay, a professor of computer science at Stanford and co-author of the new study published online at arXiv.org, was quoted as saying in a news release from Stanford on Wednesday.

The subjects took turns typing or speaking about 100 phrases sourced from a standard library of everyday phrases used in text-based research - phrases such as "physics and chemistry are hard," "have a good weekend" and "go out for some pizza and beer" - while the testing app recorded their times and accuracy rates. Half the subjects performed the task in English using the QWERTY keyboard; the other half conducted the test in their native Mandarin Chinese using Apple iOS' Pinyin keyboard.

"Speech recognition is something that's been promised to us for decades, but it has never worked very well," Landay said about the experiment. "But we were noticing that in the past two to three years, speech recognition was actually improving a lot, benefiting from big data and deep learning to train its neural networks to produce faster, more accurate results. So we decided to formally test it against humans."

The results: for English, speech recognition was three times faster than typing, and the error rate was 20.4 percent lower; in Mandarin Chinese, speech was 2.8 times faster, with an error rate 63.4 percent lower than typing.

"We knew speech recognition is pretty good, so we expected it to be faster, but we were actually quite surprised to find that it was almost three times faster than typing on a keyboard," said co-author Sherry Ruan, a computer science PhD student at Stanford who helped run the experiments.

Although only the speech recognition software from Baidu, a web services company headquartered in Beijing, China, and listed on NASDAQ Stock Market in New York, the United States, was used, the researchers suspect that other high-accuracy speech engines perform at a similar level and they hope that given the results of their experiment, engineers will be encouraged to design user interfaces that take better advantage of the speech recognition technology.

"We should put speech in more applications than just typing an email or text message," said Landay.