MEDIA POWER
by
Andrea Prat
Discussion by Tim Bresnahan
An Intriguing Point about voters who see
multiple media
• Reach
• Π(K=1)
≡
≡
Pr(A voter sees this medium)
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
MP Index (Π)
Media Usage Data
Robust w/in Class
or Calibrated
Quality of Candidate
Majority of all voters
… 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
Media Used
Frequency of Use
Other intensity
Segments
Demographic
Psychographic
Ideological
Prior
Moralizing
Geographic
Swing States
Media Markets
Ads by Candidates
Voter Response
Bayesian
limited bandwidth.
sophistication about bias
Other rational inattention
Emotive
Moralizing
Competitive Interference
Vote / Prefer / Know of
Election Outcomes
Quality of Candidate
Issues (heterog. qual. assessment)
Coalition (mult. issues)
Majority of all voters
Swing States
Turnout: Mobilize Base
Who 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
Media Used
Frequency of Use
Other intensity
Segments
Demographic
Psychographic
Ideological
Prior
Moralizing
Geographic
Swing States
Media Markets
Ads by Candidates
Voter Response
Bayesian
limited bandwidth.
sophistication about bias
Other rational inattention
Emotive
Moralizing
Competitive Interference
Vote / Prefer / Know of
Election Outcomes
Quality of Candidate
Issues (heterog. qual. assessment)
Coalition (mult. issues)
Majority of all voters
Swing States
Turnout: Mobilize Base
Who 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?)