The Design of Online Advertising Markets

Edelman, Benjamin. “The Design of Online Advertising Markets.” Chap. 15 in The Handbook of Market Design, edited by Nir Vulkan, Alvin E. Roth, and Zvika Neeman. Oxford University Press, 2013.

Because the market for online advertising is both new and fast-changing, participants experiment with all manner of variations. Should an advertiser’s payment reflect the number of times an ad was shown, the number of times it was clicked, the number of sales that resulted, or the dollar value of those sales? Should ads be text, images, video, or something else entirely? Should measurement be performed by an ad network, an advertiser, or some intermediary? Market participants have chosen all these options at various points, and prevailing views have changed repeatedly. Online advertising therefore presents a natural environment in which to evaluate alternatives for these and other design choices. In this piece, I review the basics of online advertising, then turn to design decisions as to ad pricing, measurement, incentives, and fraud.

Social Comparisons and Deception Across Workplace Hierarchies: Field and Experimental Evidence

Edelman, Benjamin, and Ian Larkin. “Social Comparisons and Deception Across Workplace Hierarchies: Field and Experimental Evidence.” Organization Science 26, no. 1 (January-February 2015): 78-98.

We examine how unfavorable social comparisons differentially spur employees of varying hierarchical levels to engage in deception. Drawing on literatures in social psychology and workplace self-esteem, we theorize that negative comparisons with peers could cause either junior or senior employees to seek to improve reported relative performance measures via deception. In a first study, we use deceptive self-downloads on SSRN, the leading working paper repository in the social sciences, to show that employees higher in a hierarchy are more likely to engage in deception, particularly when the employee has enjoyed a high level of past success. In a second study, we confirm this finding in two scenario-based experiments. Our results suggest that longer-tenured and more successful employees face a greater loss of self-esteem from negative social comparisons and are more likely to engage in deception in response to reported performance that is lower than that of peers.

SaferTaxi: Connecting Taxis and Passengers in South America (teaching materials) with Peter Coles

Coles, Peter, and Benjamin Edelman. “SaferTaxi: Connecting Taxis and Passengers in South America.” Harvard Business School Case 913-041, April 2013. (Revised October 2014.) (educator access at HBP. request a courtesy copy.)

SaferTaxi, a taxi booking service in South America must develop its mobilization strategy; that is, it must attract enough passengers and drivers to make its service worthwhile for all. Drivers hesitate to pay for SaferTaxi’s smartphones and service unless these will deliver passenger bookings—and passengers have no reason to sign up unless drivers are available. Meanwhile, regulators question the permissibility of online taxi booking in light of regulatory requirements, and some existing taxi booking vendors feel threatened by SaferTaxi’s efforts to enter the market. As SaferTaxi attempts to satisfy these diverse constituents, international competition looms. What should SaferTaxi’s founders do next?

Teaching Materials:

SaferTaxi: Connecting Taxis and Passengers in South America – Teaching Note (HBP 913063)

Airbnb (teaching materials) with Michael Luca

Edelman, Benjamin, and Michael Luca. “Airbnb (A).” Harvard Business School Case 912-019, December 2011. (Revised March 2012.) (educator access at HBP. request a courtesy copy.)

After widely-publicized complaints of destructive guests and unreliable hosts, online apartment rental site Airbnb explores mechanisms to facilitate trust between guests and hosts. Flexible online reputation systems can collect and share information with ease, but Airbnb must decide which information guests and hosts should have to provide and how much flexibility each should have in selecting who to do business with. A full-featured system could provide all the information users have been requesting, but would it be too complicated for routine use?


Airbnb (B) – Supplement (HBP 912019)

Teaching Material:

Airbnb (A) and (B) – Teaching Note (HBP 912021)

Adverse Selection in Online ‘Trust’ Certifications and Search Results

Edelman, Benjamin. “Adverse Selection in Online ‘Trust’ Certifications and Search Results.” Electronic Commerce Research and Applications 10, no. 1 (January-February 2011): 17-25.

Widely used online “trust” authorities issue certifications without substantial verification of recipients’ actual trustworthiness. This lax approach gives rise to adverse selection: the sites that seek and obtain trust certifications are actually less trustworthy than others. Using an original dataset on web site safety, I demonstrate that sites certified by the best-known authority, TRUSTe, are more than twice as likely to be untrustworthy as uncertified sites. This difference remains statistically and economically significant when restricted to “complex” commercial sites. Meanwhile, search engines create an implied endorsement in their selection of ads for display, but I show that search engine advertisements tend to be less safe than the corresponding organic listings.

Least-Cost Avoiders in Online Fraud and Abuse

Edelman, Benjamin. “Least-Cost Avoiders in Online Fraud and Abuse.” IEEE Security & Privacy 8, no. 4 (July-August 2010): 78-81.

Web users face considerable fraud, malfeasance, and economic harm that system operators could prevent or mitigate. Although the legal system can respond, regulations have mixed results. I examine the applicable legal rules that constrain online fraud and the economic underpinnings to identify whether those rules assign responsibility to the parties best positioned to take action.

The Pathologies of Online Display Advertising Marketplaces

Edelman, Benjamin. “The Pathologies of Online Display Advertising Marketplaces.” Art. 2. SIGecom Exchanges (June 2010).

Display advertising marketplaces place “banner” ads on all manner of popular sites. While these services are widely used, they suffer significant challenges, including weak user response and low accountability for both advertisers and web site publishers. I survey a few major challenges, flagging possible areas for future research.

Who Owns Metrics?: Building a Bill of Rights for Online Advertisers

Edelman, Benjamin. “Who Owns Metrics?: Building a Bill of Rights for Online Advertisers.” Journal of Advertising Research 49, no. 4 (December 2009). (Adapted from Towards a Bill of Rights for Online Advertisers.)

I offer five rights to protect advertisers from increasingly powerful ad networks-avoiding fraudulent charges for services not rendered, guaranteeing data portability so advertisers get the best possible value, and assuring price transparency so advertisers know what they’re buying. I explain the need for these rights by presenting specific practices causing particular concern.

The Dark Underbelly of Online Advertising

Edelman, Benjamin. “The Dark Underbelly of Online Advertising.” HBR Now. (November 17, 2009).

The Internet is sold to advertisers as a highly measurable medium that is the most efficient way to target exactly the right customers. But online advertising is also easily subverted–letting fraudsters claim advertising fees for work they did not actually do. The trickiest frauds deceive advertisers so effectively that measurements of ad effectiveness report the fraudsters as exceptionally productive and high quality, rather than revealing that their traffic was actually worthless. This is a quiet scandal. In a time of tightening ad budgets, losses to advertising fraud come straight from the bottom line–but savings can be equally dramatic. Here’s a look behind the veil–an explanation of ad practices that have cheated even the Web’s largest advertisers. Advertising scams take plenty of victims, both witting and not, but I offer strategies to help determined marketers protect themselves.

Securing Online Advertising: Rustlers and Sheriffs in the New Wild West

Edelman, Benjamin. “Securing Online Advertising: Rustlers and Sheriffs in the New Wild West.” In Beautiful Security, edited by Andy Oram and John Viega. O’Reilly Media, Inc., 2009. (Korean translation.)

Read the news of recent computer security guffaws, and it’s striking how many problems stem from online advertising. Advertising is the bedrock of web sites that are provided without charge to end users, so advertising is everywhere. But advertising security gaps are equally widespread: from “malvertisement” banner ads pushing rogue anti-spyware software, to click fraud, to spyware and adware, the security lapses of online advertising are striking.

During the past five years, I have uncovered hundreds of online advertising scams defrauding thousands of users–not to mention all the web’s top merchants. This chapter summarizes some of what I’ve found–and what users and advertisers can do to protect themselves.