The Justice Department has called witnesses who testified about Google's payments, billions of dollars annually, to smartphone makers and wireless companies to make Google search the default on devices, and win more users.
Others testified how search dominance led to clout in online advertising, including the ability to quietly raise ad prices.
He also testified about how Google used machine learning tools that it developed to improve its search.
Nayak's discussions of improving search appeared to downplay the role that search query volume played, implicitly disagreeing with Microsoft (MSFT.O) CEO Satya Nadella's arguments that his company needed more search queries to improve its Bing search engine but was being blocked by Google.
Nayak also testified that Google compared its results to answers from Microsoft's search engine Bing, and found Bing to be lower quality.
Eric Gaillard, Pandu Nayak, Satya Nadella's, Amit Mehta, Nayak, Bing, Diane Bartz, Marguerita Choy
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