All three of the leading digital assistants are getting better at responding to human questions, but one still holds the top spot.

For the second year in a row, Loup Ventures found that Google Assistant answered more questions correctly than Apple's Siri or Amazon's Alexa in its annual IQ test. The study tested smartphone-based digital assistants by asking each the same 800 questions about finding nearby places, ordering goods, navigating and more. The study evaluated whether the assistants correctly understood the question and the accuracy of their responses.

Google Assistant correctly answered 93% of the questions and understood all 800, according to Loup Ventures. Siri came in second, answering 83% correctly and misunderstanding two questions. Alexa answered 80% correctly but only misunderstood one, according to the study.

The ranking remained consistent with that of last year's study, but all three assistants improved their scores, Loup Ventures said. In July 2018, Google Assistant answered 86% of questions correctly while Siri answered 79% correctly. Alexa made the biggest jump from year to year, improving nearly 19 percentage points from an accuracy score of just 61% in 2018.

"Many of the same trends continue; Google outperforms in information-related questions, Siri handles commands best, and the ranking of utility based on the number of questions answered has remained the same (Google Assistant, Siri, Alexa)," Loup Ventures wrote in a blog post. "[B]ut there have been dramatic improvements on each platform and in each category in the few short years that we have been tracking the progress of digital assistants."

This year, Siri outperformed Google Assistant in the command category, according to the study. Both "far outperformed" Amazon's Alexa in this category, which the study's authors attributed to the fact that both are baked into the phones' operating systems, while Alexa is part of a third-party app.

While one might expect Alexa to be best at questions about ordering goods, Loup Ventures said Google Assistant actually had the widest lead in the commerce category. Google Assistant correctly answered 92% of questions in the section, while Alexa answered 71% correctly and Siri 68%. Still, the researchers said they don't think a significant number of consumers are making purchases through voice commands, based on consumer surveys and personal experience.

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