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Page 1: The Potential and Perils of Election Prediction Using Social Media Sources

The Potential and Perils of Election Prediction Using

Social Media Sources

Federico Nanni and Josh CowlsUniversity of Mannheim/Comparative

Media Studies, MIT

Page 2: The Potential and Perils of Election Prediction Using Social Media Sources

Reasons to be cheerful+ Social media data is (often) cheap+ Phone response rates are in decline+ More granularity available?

CostUtility

Traditional inferential model Social media model

Page 3: The Potential and Perils of Election Prediction Using Social Media Sources

Reasons to be doubtful- Myriad reliability issues...– Difficult to establish the meaning of

latent messages– Platform specific behaviours (e.g.

hashtags, likes) are not always understood

– Political discourse often laced with e.g. sarcasm

- The ethics of collecting and using social media data

Page 4: The Potential and Perils of Election Prediction Using Social Media Sources

Results to date have been mixed...• A meta-analysis found little evidence that

using Twitter to predict elections is better than chance in the aggregate (Gayo-Avello, 2013)

• Nonetheless, social media can provide an ‘early warning system’ for a candidate’s momentum (Jensen and Anstead, 2013)

• Big problem: what’s in a name?

Page 5: The Potential and Perils of Election Prediction Using Social Media Sources

Our approach: intention over attention

• Most models count references to candidates’ or parties’ names – measuring attention

• Other models use sentiment analysis, seeking to ascertain emotion responses to candidates

• We built an intention model, collecting instances of vote declarations for specific candidates

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Case study• Context: Labour and the Lib Dems

required new leaders in 2015 (after a polling fail!)

• Leadership elections conducted in summer 2015– Lib Dems: two candidates (Tim Farron,

Norman Lamb)– Labour: four candidates (Jeremy Corbyn,

Andy Burnham, Yvette Cooper, Liz Kendall)

Page 7: The Potential and Perils of Election Prediction Using Social Media Sources

Advantages of our case• Primary candidates’ names easier to

isolate than ambiguous party names (“Labour”, “Liberal”)

• Party elections are a minority sport – better signal to noise ratio?

• Start and end dates clear; postal vote system ensured greater period of decision-making

Page 8: The Potential and Perils of Election Prediction Using Social Media Sources

Method Wrote Python scripts to collect tweets which:

Mentioned the name of a candidate Included a specific declaration to vote (“I’ll vote

for...”, “I’m voting for” etc) Cleaned data

Removed non-declarations (“I’m not voting for...”) Ascertained preferred candidate in ambiguous cases

Final dataset: 1361 valid declarations for Lib Dem race and 17617 for Labour

Page 9: The Potential and Perils of Election Prediction Using Social Media Sources

Analysis (1)

Page 10: The Potential and Perils of Election Prediction Using Social Media Sources

Analysis (2)

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Key successes• ‘Intention’ model beat out ‘Attention’

model in 5 out of 6 races, and in both races overall

• Lib Dem prediction accuracy close to traditional margin of error (MOE = 3.5)

• Caught Corbyn’s success to a high degree of accuracy (MOE = 2)

Page 12: The Potential and Perils of Election Prediction Using Social Media Sources

Reflections and future work• Tough to generalise successes – specific

cases, particular platform. (How) would this work for:– Multi-state process (e.g. US primaries)?– General elections?

• Despite ongoing challenges, social media will surely play a key role in the future of accurate election prediction