the 2016 presidential contest was the first real social-media election. given the race<u+2019>s often toxic and divisive rhetoric, it was a mixed blessing for the two giants of the industry. facebook inc. and twitter inc. were central in the shaping of voters<u+2019> perceptions of the u.s. political climate and the two presidential candidates, republican donald trump and democratic rival hillary clinton. one in five social-media users modified their views about a political or social issue because of a social-media post, according to a pew research survey published last month. mr. trump, in particular, used twitter as a primary means of communicating with supporters in a way no candidate has before, bypassing traditional news outlets that he often accused of conspiring against his candidacy. meanwhile, facebook often hosted new sources of news and information that operate under different standards than the traditional media, providing competing perspectives<u+2014>in some cases based on minimal or even fake evidence. on the eve of the election, president barack obama raised concerns about misinformation online and its effect on the election. "as long as it<u+2019>s on facebook and people can see it, as long as it<u+2019>s on social media, people start believing it. it creates this dust cloud of nonsense,<u+201d> he said during a rally for mrs. clinton in ann arbor, mich. facebook was seen as central to the conversation. <u+201c>if anything there was an absolute tsunami of information where people talked about this election seemingly nonstop for well over a year,<u+201d> venture capitalist peter thiel said in an interview. mr. thiel, who is a facebook director, was mr. trump<u+2019>s most prominent supporter in silicon valley. mr. obama tapped social media to connect with voters in 2012, but it wasn<u+2019>t as widely used. in the past four years, these sites have added hundreds of millions more users, and smartphones have taken over. <u+201c>the ease of use, the ubiquity, the fact that it<u+2019>s on our phones, in our pockets has made it incredibly powerful,<u+201d> said sarah roberts, an assistant professor of information studies at the university of california, los angeles. on wednesday, facebook and twitter played down their roles. <u+201c>scapegoating social media for an election result ignores the important roles that candidates, voters, and journalists play in the democratic process,<u+201d> a spokesman for twitter said. a facebook spokeswoman said the social network <u+201c>was just one of many ways people received their information<u+2014>and was one of the many ways people connected with their leaders, engaged in the political process and shared their views.<u+201d> on election day, twitter users sent more than 75 million election-related tweets world-wide before president-elect donald trump declared victory, according to the company. facebook says 115.3 million people<u+2014>roughly 10% of its daily active users world-wide<u+2014>liked, posted, commented and shared content related to the election about 716.3 million times. social media has become a <u+201c>battleground of ideas,<u+201d> said david bozell, president of foramerica, a conservative group with a large presence on facebook that spent millions of dollars on advertising to build an audience online. unlike traditional media, facebook and twitter shy away from making editorial decisions. that hands-off approach has allowed fake news to fester, critics charge, while companies raked in more advertising dollars from the additional time users spent posting, liking, commenting and sharing election-related content. facebook<u+2019>s main stream of posts <u+201c>optimizes for engagement,<u+201d> said bobby goodlatte, a former facebook product designer in a public post on the social network. <u+201c>as we learned in this election, bullshit is highly engaging.<u+201d> one silicon valley executive who opposed mr. trump questioned social media<u+2019>s role. <u+201c>technology has a role in that we...provide communication platforms for the rest of the country,<u+201d> startup investor dave mcclure said at a conference wednesday. <u+201c>just like the cable news networks, just like talk radio, it<u+2019>s a propaganda medium.<u+201d> in recent months, debate has raged over how facebook and twitter enable the spread of rumors and fake news because of a lack of oversight. after facebook fired some editors and put an algorithm in charge of its <u+201c>trending topics<u+201d> feature in late august, a bogus report surfaced on facebook from conservative site endingthefed.com saying that fox news anchor megyn kelly was fired because she secretly backed mrs. clinton for president. matt mahan, chief executive of brigade media inc., a <u+00a0>political social network that strives to be bipartisan, said the truth on social media is <u+201c>a very tough thing to enforce.<u+201d> (mr. mahan supported mrs. clinton.) <u+201c>that<u+2019>s going to be one of the major topics coming out of this election,<u+201d> he said. <u+201c>we<u+2019>re going to be talking about misinformation and who<u+2019>s the arbiter of the truth.<u+201d> <u+2014>rolfe winkler contributed to this article. write to deepa seetharaman at deepa.seetharaman@wsj.com
central role of facebook, twitter among  electorate gets mixed reviews - wsj
deepa seetharaman