Guest Post: Who won the debate? Ask Twitter

Image by Donkey Hotey via Flickr

As expected, last night’s VP debate was engaging, to say the least. David Lazer’s lab was at it again, ana­lyzing real-​​time Twitter data to gauge the public’s response to the event. Below, Lazer explains their Twitter “win­ning index,” which fluc­tu­ated across the two can­di­dates’ performances.


Twitter allows real-​​time cal­cu­la­tion of audi­ence responses to the debate.  The “Win­ning Index” pro­duced by our lab shows how dif­ferent groups eval­u­ated the can­di­dates’ per­for­mances during the debate.  The index tracks the extent to which tweets from a group of users men­tion a can­di­date with ‘win­ning words” like “won” or “vic­tory.”  The index shows clear par­tisan dis­agree­ment when the debate ended at 10:30 (22:30).  The blue line — com­prised of Demo­c­ratic leaning tweeters — declares vic­tory for Biden.  The red line — com­prised of Repub­lican leaning tweeters — declares vic­tory for Ryan.  Inter­est­ingly, the bi-​​partisan tweeters — many of whom are media pro­fes­sionals — appear to side with the Democ­rats on this one.

Inspec­tion of the index and another tool, tells the story of how the debate was “won” (in the minds of these dif­ferent groups).  The Demo­c­ratic tweeters began in the dol­drums, tracking closely to the Repub­lican line, sug­gesting they think that Ryan is win­ning.  At around 9:30, how­ever, there is a dra­matic change.  The blue line soars and remains high for the rest of the debate.  This appears to be when Biden restored the con­fi­dence of anx­ious Democ­rats.  Repub­li­cans soon follow suit about 10 min­utes later declaring Ryan is win­ning.  The green group is less extreme in its reac­tion until the end of the debate.

There are early signs, how­ever, that the green group was favoring Biden.  The sen­ti­ment index tracks the affect of words used in tweets about the can­di­dates.  Greens and showed pro-​​Obama/​Biden sen­ti­ment con­sis­tently through most of the debate.