Alphabet Inc.’s (GOOGL) Google has developed artificial intelligence that has much more brain power than Apple Inc.’s (AAPL) virtual assistant Siri, according to a new academic paper. Based on data compiled by a trio of Chinese researchers who have developed an IQ test for AI, Google’s score significantly outperforms Siri and Bing—yet with an IQ less than that of a 6-year-old. (See also: Artificial Intelligence Will Add $15.7 Trillion to the Global Economy: PwC.)

Researchers Feng Liu, Yong Shi and Yin Liu carried out tests throughout 2016, which ranked Google’s AI IQ at 47.28, just shy of the average IQ they found for a human 6-year-old: 55.5. Siri’s IQ fell well below at 23.9, which was also lower than Microsoft Corp.’s (MSFT) Bing and Baidu, at 31.98 and 32.92, respectively. For comparison’s sake, the average 18-year-old has an IQ of 97, according to the study.

AI Improves Significantly

“The results so far indicate that the artificial intelligence systems produced by Google, Baidu, and others have significantly improved over the past two years but still have certain gaps as compared with even a six-year-old child,” according to the research.

While AI’s IQ scores are still dwarfed by that of the average human adult, Google and Microsoft have all seen their research and development (R&D) pay off in increasingly intelligent bots. In 2014, Google’s IQ score was just 26.5, while Microsoft’s was 13.5.

Tech titans are making significant investments in AI research. DeepMind, a U.K.artificial intelligence company bought by Google in 2014, has tripled the amount of money it spends on top talent, according to published reports. The investments are expected to fuel breakthroughs in areas such as speech and image recognition, automatically serving business functions such as advertisements. According to a recent report by global auditing and consulting firm PwC, automation is set to boost global GDP by as much as 14% by 2030. (See also: Starbucks to Use AI to Guess Your Order and Tempt You to Buy More.)

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