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How Much Influencer Marketing Is Undisclosed? Evidence from Twitter

Author

Listed:
  • Daniel Ershov
  • Yanting, He
  • Stephan Seiler

Abstract

We study the disclosure of influencer posts on Twitter across a large set of brands based on a unique data set of over 100 million posts and a novel classification method to detect undisclosed sponsorship. Using our preferred empirical specification we find that 96% of sponsored posts are not disclosed. This result is robust to a series of specification tests and even a lower bound classification still yield an undisclosed share of 82%. Despite stronger enforcement of disclosure regulations, the share of undisclosed posts decreases only slightly over time. Compared to disclosed posts, undisclosed posts tend to be associated with young brands with a large Twitter following. Using an online survey we find that many consumers are not able to identify sponsored content without disclosure. Our findings highlight a potential need for further regulatory scrutiny and suggest that researchers studying influencers must account for non-disclosed sponsored content.

Suggested Citation

  • Daniel Ershov & Yanting, He & Stephan Seiler, 2023. "How Much Influencer Marketing Is Undisclosed? Evidence from Twitter," CESifo Working Paper Series 10743, CESifo.
    • Handle: RePEc:ces:ceswps:_10743
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    References listed on IDEAS

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    Full references (including those not matched with items on IDEAS)

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    JEL classification:

    • C55 - Mathematical and Quantitative Methods - - Econometric Modeling - - - Large Data Sets: Modeling and Analysis
    • M31 - Business Administration and Business Economics; Marketing; Accounting; Personnel Economics - - Marketing and Advertising - - - Marketing
    • M37 - Business Administration and Business Economics; Marketing; Accounting; Personnel Economics - - Marketing and Advertising - - - Advertising
    • M38 - Business Administration and Business Economics; Marketing; Accounting; Personnel Economics - - Marketing and Advertising - - - Government Policy and Regulation

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