Comments on Della Vigna and Kennedy

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Comments on Della Vigna and Kennedy Joel Waldfogel Moscow October 28, 2011

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Comments on Della Vigna and Kennedy. Joel Waldfogel Moscow October 28, 2011. Neat paper!. Oodles of evidence trained on question: “does joint ownership of media outlet and movie studio cause better reviews?” “oodles” means N → ∞ Compelling controls, believable estimate Comments - PowerPoint PPT Presentation

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Page 1: Comments on Della Vigna and Kennedy

Comments on Della Vigna and Kennedy

Joel WaldfogelMoscow

October 28, 2011

Page 2: Comments on Della Vigna and Kennedy

Neat paper!

• Oodles of evidence trained on question: “does joint ownership of media outlet and movie studio cause better reviews?”– “oodles” means N → ∞

• Compelling controls, believable estimate• Comments– Earnest praise– Finding’s meaning– Effect of “concentration”

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• Elements of a good story…

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villains

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heroes

• Bias-detecting sleuths

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Characters you’re not sure about until the end

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Make a wish

• Suppose you wanted to know whether films receive better reviews at studio-owned media outlets

• Wish list: it would be nice to have a context with – Change in ownership, with reviews before and after– Data on multiple outlets’ reviews of same movies– Half a million observations

• Amazingly, this is what Stefano and Alex have!

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Drum roll, please

• We have countenanced the devil• …and what does he look like?

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Regular vs diabolical reviews

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Another perspective

Answer: 3 points at Fox-owned, 0 at Time Warner, on a mean review of 60

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Economic vs statistical significance

• N → ∞– SD of mean: σ/√N– Many things will become statistically significant – Will see *** in tables, but size matters

• Aside– Suppose N had been merely 100,000– Could have convinced me of no effect– Effect is hard to detect

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Implications of results

• Does ownership affect reviews?– A series of case studies– Yes at Fox, no at Time Warner– Yes for some reviewers, no for others

• Would like an explanation of why sometimes yes

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What is the policy takeaway?

• Don’t let Murdoch own stuff?

• or

• “on balance, no evidence that it matters much”

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Paper Motivation

• “Does Media Concentration Lead to Biased Coverage?”

• What do you think when you hear “media concentration”?

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Possible effects of “concentration”

• Product positioning incentives associated with joint ownership– Internalization of business stealing externalities– This paper’s not about that

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Competition and product quality?

• Does competition keep reviewers honest vs undermining ability to finance high fixed costs

• Would require variation in amount of competition• Not what this paper wants to be about

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Product positioning and owner preferences

• Related to– Podolny and Scott-Morton • what movitates wine makers – “Love or Money?”

– Race and ownership • FCC had traditionally tried to promote minority

ownership

• Maybe change title– “concentration” evokes the wrong imagery here

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Another point of contact

• This is a merger retrospective– Cf. Ashenfelter, Hosken, etc.

• Usually, look at price changes following merger– Selected sample of allowable mergers– Here, merger likely exogenous

• Post-merger product repositioning

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Thanks

• Neat paper!• Impressive exercise• Convincing estimates