media power by andrea prat discussion by tim bresnahan

MEDIA POWER by

Andrea Prat

Discussion by Tim Bresnahan

An Intriguing Point about voters who see multiple media

• Reach ≡ Pr(A voter sees this medium)• Π(K=1) ≡ f(Pr(A voter saw this medium most recently))

• Key idea: a consumer who sees multiple media is less influenced by any one of them• In the case of K=1 (only recalling one message (wlog most recent message)

this comes down to “attention share”

Three Elements of an Index …

Audience Statistics Voter Response Election Outcomes

Three Elements of an Index …

Audience Statistics Voter Response Election Outcomes

Reach

Media Usage Data Robust w/in Classor Calibrated

Quality of CandidateMajority of all voters

MP Index (Π)

… mean more assumptions.

Voter Response Assumptions

• Bayesian voters. • Potentially limited bandwidth. • Potentially “sophisticated” about biased media.

• Defining the class within which approach is “bounded,” “robust”• Obvious first class to consider.

Alternatives (from advertising and PE)

Audience Statistics Voter Response Election Outcomes

Media UsedFrequency of Use Other intensitySegments Demographic Psychographic Ideological Prior Moralizing Geographic Swing States Media MarketsAds by Candidates

Bayesian limited bandwidth. sophistication about biasOther rational inattentionEmotiveMoralizingCompetitive Interference

Vote / Prefer / Know of

Quality of CandidateIssues (heterog. qual. assessment)Coalition (mult. issues)

Majority of all votersSwing StatesTurnout: Mobilize BaseWho is Pivotal?

Picking from this menu (1)If voters assess issues, not “quality”• Coalition formation and diverse interests• e.g. Budget conservatism and social conservatism• Heterogeneous responses to specific messages

• Are there additional constraints on media?• What to tell centrist voters if their responses are different sign from base?

• “MP” can’t capture this kind of heterogeneity • All voter reactions are the same direction

• Strength potentially muted by ideology (prior), “sophistication” or high bandwidth

Picking from this Menu (2)If Moralizing/Ideological appeals are like emotive appeals in product advertising

• Let total exposures =r*f= (reach*frequency)• Frequency of exposure, in some contexts, works to create emotional

bond so that ∂response(r,f)/∂r < ∂response(r,f)/∂r * (f/r)• If political messages work like this, it weights up intensive use of one

medium by voters• Or of media transmitting similar messages (Fox, WSJ is big in paper)• Application to positive political messages?• Application to negative ones?

Picking from this menu (3)Advertising by candidates or 2 evil media moguls

Picking from this menu (4) Getting out the vote in the base vs. moving swing voters

• Opposite signs in power index for stronger media that segment by hitting base vs stronger media that segment by hitting swing voters• Robustness is, ahem, challenging

Some Breathless Empirical Finding Reports

Highest-Ranked Newspaper is ~10th

• NYT is also ~10th in reach

The Top Three Media Conglomerates could swing an election• Fox & WSJ + CNN + Comedy Central + MSNBC + NBC

• Translation??? “The Top Two Parties could swing an election”

Finished … the alternatives

Audience Statistics Voter Response Election Outcomes

Media UsedFrequency of Use Other intensitySegments Demographic Psychographic Ideological Prior Moralizing Geographic Swing States Media MarketsAds by Candidates

Bayesian limited bandwidth. sophistication about biasOther rational inattentionEmotiveMoralizingCompetitive Interference

Vote / Prefer / Know of

Quality of CandidateIssues (heterog. qual. assessment)Coalition (mult. issues)

Majority of all votersSwing StatesTurnout: Mobilize BaseWho is Pivotal?

Fin

Old slides follow

If it were advertising --

Metrics• Reach • Frequency • Impressions• Segments• Various targeted versions

(“Reach into swing voters….” “… into swing states”)

Impacts• On sales (voter turnout), on

knowledge of product (candidate), on perception of product (candidate) on intentions (to vote, buy)• Impacts of reach, frequency the

same or different?• Competitive Interference • Etc.

An Index of media power

• Move from media markets to individual voter information sources (in the simplest case, Attention Shares)• Voter rational inattention, potentially limited bandwidth, potentially

“sophisticated” about biased media• “worst case” biased media• An improvement on reach• reach: pr(voter exposed to this medium)• MP(K=1): pr(voter’s last exposure was to this medium)• Has all the strengths and weaknesses of reach measures

Mergers in media distribution industries• Can’t use market power indexes• Can’t use media power indexes

Media Power index is high

• Media is pretty unconcentrated: might be no problem?• BUT, this paper points out, many voters use few media (most

frequently TV networks) • And takes the view of media => voters of that

Robustness

• Rationally inattentive voters deciding on candidate quality • Various robustnesses within that

• Emotive Appeals• Voter preferences over issues

Some Positive Political Economy Things• Swing States• Too many messages from one source or too many uncontested

messages from one source?• Getting out the base• Creating coalitions (those two definitions of conservative?)