Do We Need a Speedometer for Artificial Intelligence?

Microsoft said last week that it had achieved a new record for the accuracy of software that transcribes speech. Its system missed just one in 20 words on a standard collection of phone call recordings--matching humans given the same challenge. The result is the latest in a string of recent findings that some view as proof that advances in artificial intelligence are accelerating, threatening to upend the economy. Some software has proved itself better than people at recognizing objects such as cars or cats in images, and Google's AlphaGo software has overpowered multiple Go champions--a feat that until recently was considered a decade or more away. Companies are eager to build on this progress; mentions of AI on corporate earnings calls have grown more or less exponentially.