First Look

November 21, 2017

Among the highlights included in new research papers, case studies, articles, and books released this week by Harvard Business School faculty:

Employers pay too much attention to degrees

Companies increasingly slap requirements for academic degrees on many jobs even though doing so may get them fewer qualified candidates. In a report, Joseph B. Fuller and Manjari Raman show employers why non-degreed candidates not only can give hirers a better talent pool to draw from, but at less cost. Dismissed by Degrees: How Degree Inflation Is Undermining U.S. Competitiveness and Hurting America's Middle Class.

Is it time to reach beyond our core compentency?

The case study CareMore Health Systems looks at that group’s growth discussions and whether it should expand coverage beyond its 75,000 Medicare Advantage members. One option: target that same population but add new geographic markets. Another option: serve new populations such as younger or low-income subscribers. “This case allows for a discussion of whether diversifying to serve these new populations was the key to ensuring CareMore’s successful growth or a distraction from its core competency of caring for seniors,” according to authors Robert S. Huckman and Brian W. Powers. CareMore Health Systems.

Other new publications from Harvard Business School faculty are listed below.

— Sean Silverthorne
  • forthcoming
  • Journal of Political Economy

Internalizing Global Value Chains: A Firm-Level Analysis

By: Alfaro, Laura, Pol Antràs, Davin Chor, and Paola Conconi

Abstract—In recent decades, advances in information and communication technology and falling trade barriers have led firms to retain within their boundaries and in their domestic economies only a subset of their production stages. A key decision facing firms worldwide is the extent of control to exert over the different segments of their production processes. We describe a property-rights model of firm boundary choices along the value chain that generalizes Antràs and Chor (2013). To assess the evidence, we construct firm-level measures of the upstreamness of integrated and non-integrated inputs by combining information on the production activities of firms operating in more than 100 countries with input-output tables. In line with the model's predictions, we find that whether a firm integrates upstream or downstream suppliers depends crucially on the elasticity of demand for its final product. Moreover, a firm's propensity to integrate a given stage of the value chain is shaped by the relative contractibility of the stages located upstream versus downstream from that stage, as well as by the firm's productivity. Our results suggest that contractual frictions play an important role in shaping the integration choices of firms around the world.

Publisher's link:

  • forthcoming
  • Quantitative Marketing and Economics

Aggregation of Consumer Ratings: An Application to

By: Dai, Weijia, Ginger Jin, Jungmin Lee, and Michael Luca

Abstract—Because consumer reviews leverage the wisdom of the crowd, the way in which they are aggregated is a central decision faced by platforms. We explore this "rating aggregation problem" and offer a structural approach to solving it, allowing for (1) reviewers to vary in stringency and accuracy, (2) reviewers to be influenced by existing reviews, and (3) product quality to change over time. Applying this to restaurant reviews from, we construct an adjusted average rating and show that even a simple algorithm can lead to large information efficiency gains relative to the arithmetic average.

Publisher's link:

  • November 2017
  • American Economic Review

Interest Rate Pass-Through: Mortgage Rates, Household Consumption, and Voluntary Deleveraging

By: Di Maggio, Marco, Amir Kermani, Benjamin Keys, Tomasz Piskorski, Rodney Ramcharan, Amit Seru, and Vincent Yao

Abstract—Exploiting variation in the timing of resets of adjustable-rate mortgages (ARMs), we find that a sizable decline in mortgage payments (up to 50%) induces a significant increase in car purchases (up to 35%). This effect is attenuated by voluntary deleveraging. Borrowers with lower incomes and housing wealth have significantly higher marginal propensity to consume. Areas with a larger share of ARMs were more responsive to lower interest rates and saw a relative decline in defaults and an increase in house prices, car purchases, and employment. Household balance sheets and mortgage contract rigidity are important for monetary policy pass-through.

Publisher's link:

  • forthcoming
  • Review of Financial Studies

Asset Price Dynamics in Partially Segmented Markets

By: Greenwood, Robin, Samuel Gregory Hanson, and Gordon Y. Liao

Abstract—We develop a model in which capital moves quickly within an asset class but slowly between asset classes. While most investors specialize in a single asset class, a handful of generalists can gradually reallocate capital across markets. Upon the arrival of a large supply shock, prices of risk in the directly impacted asset class become disconnected from those in others. Over the long run, capital flows between markets and prices of risk become more closely aligned. While prices in the directly impacted market initially overreact to the supply shock, we show that prices in related asset classes underreact under plausible conditions. We use the model to assess event-study evidence on the impact of recent large-scale asset purchases by central banks.

Publisher's link:

Governance Through Shame and Aspiration: Index Creation and Corporate Behavior

By: Chattopadhyay, Akash, Matthew D. Shaffer, and Charles C.Y. Wang

Abstract—We study whether stock indexes can be a mechanism for transforming long-standing corporate behavior. After decades of low corporate profitability in Japan, the JPX-Nikkei400 Index was introduced in 2014. Each year the index selected 400 large and liquid firms deemed best performing in terms of profitability; membership is considered highly prestigious. We document that index-inclusion incentives have led firms to increase return on equity proportionally by 41% on average, via higher margins, efficiency, or shareholder payouts, depending on where they had slack. These incentives are driven by the prestige associated with the index, rather than direct-pecuniary or capital-market benefits. Back-of-the-envelope estimates suggest that the index-inclusion incentives accounted for 16% of the average increase in aggregate annual earnings and 20% of the growth in aggregate market capitalization over our sample period. Stock indexes can affect behavior by functioning as a source of prestige.

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Equity Concerns Are Narrowly Framed

By: Exley, Christine L., and Judd B. Kessler

Abstract—What are individuals' preferences over the payoffs of others? We show that individuals aim to achieve equity but that they narrowly bracket their equity concerns. Rather than equalize overall budgets, individuals equalize the time component or money component of budgets. Individuals believe that achieving equity within these narrow brackets is more socially appropriate than achieving overall equity. Furthermore, individuals care more about achieving equity in time than equity in money. Narrow bracketing of equity concerns and more inequity aversion in time than in money persist when individuals make allocation choices between themselves and others. Our results can help explain a variety of behavioral phenomena including the structure of social insurance programs, patterns of public good provision, and why transactions that turn money into time are often deemed repugnant.

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Online Network Revenue Management Using Thompson Sampling

By: Ferreira, Kris Johnson, David Simchi-Levi, and He Wang

Abstract—We consider a price-based network revenue management problem where a retailer aims to maximize revenue from multiple products with limited inventory over a finite selling season. As common in practice, we assume the demand function contains unknown parameters, which must be learned from sales data. In the presence of these unknown demand parameters, the retailer faces a tradeoff commonly referred to as the exploration-exploitation tradeoff. Towards the beginning of the selling season, the retailer may offer several different prices to try to learn demand at each price (“exploration” objective). Over time, the retailer can use this knowledge to set a price that maximizes revenue throughout the remainder of the selling season (“exploitation” objective). We propose a class of dynamic pricing algorithms that builds upon the simple yet powerful machine learning technique known as Thompson sampling to address the challenge of balancing the exploration-exploitation tradeoff under the presence of inventory constraints. Our algorithms prove to have both strong theoretical performance guarantees as well as promising numerical performance results when compared to other algorithms developed for similar settings. Moreover, we show how our algorithms can be extended for use in general multi-armed bandit problems with resource constraints, with applications in other revenue management settings and beyond.

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Abstract—In 1983, 14 years after the introduction of the battery-powered quartz watch, mechanical watches and the Swiss watchmakers who built them were predicted to be nearly obsolete (Landes, 1983). Unexpectedly, however, by 2008 the Swiss mechanical watchmaking industry had rematerialized to become the world’s leading exporter (in monetary value) of watches. This study reveals the process and mechanisms associated with the notion of technology reemergence, i.e., the resurgence of substantive and sustained demand for an old (legacy) technology following the introduction of a new dominant design. Drawing on the case of mechanical watchmaking, the study’s analysis reveals how technology reemergence is a decidedly cognitive process, unfolding in two phases: a first phase marked by a redefinition of meanings and values associated with the legacy technology and facilitated by mechanisms of value recombination, temporal distancing, identity marking, and conceptual bridging; and, a second phase marked by a redefinition of competitive and consumer boundaries and facilitated by mechanisms of competitive set reclamation and enthusiast consumer mobilization. This process culminates with the resurgence of innovation and coincides with a significant rise in demand for the legacy technology. These findings offer contributions to research on technology cycles, cognition, and incumbent responses to technological change.

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  • Harvard Business School Case 518-009

Clustering Customers at Chateau

This case was written for the EC course “Managing with Data Science.” The course provides MBA students with no programming experience an introduction to the field of data science and its applications in business. Students learn to (1) carefully articulate the business ask; (2) reason carefully from the ask, through metrics and models and outputs; and (3) evaluate outputs from models to (4) develop a plan for action. In this case students explore data through k-means clustering, evaluate the relevance of those clusters to a marketing question, and compare the difference between k-means and Gaussian mixture models. They also learn the value of collaborative filtering for predicting customer preferences.

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  • Harvard Business School Case 317-078

Responsibilities to Investors

No abstract available.

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  • Harvard Business School Case 618-008

CareMore Health System

CareMore Health System—a physician-founded care delivery system and health plan—had developed and refined an innovative care model for at-risk seniors enrolled in Medicare managed care (i.e., Medicare Advantage) plans. CareMore's President, Sachin Jain, and his colleagues believed their model achieved the elusive goal of improving outcomes while reducing costs. A key mandate for Jain was to scale the CareMore model beyond its current 75,000 Medicare Advantage members in California, Arizona, Nevada, and Virginia. One approach to scaling was to maintain a focus on Medicare Advantage but expand into new geographic markets. Alternatively, CareMore could focus on serving new populations. For example, CareMore had recently started serving Medicaid (i.e., younger, low-income) patients in Tennessee and Iowa. This case allows for a discussion of whether diversifying to serve these new populations was the key to ensuring CareMore’s successful growth or a distraction from its core competency of caring for seniors.

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  • Harvard Business School Case 618-009

CareMore Health System (B)

This supplement to “CareMore Health System (A)” discusses the company's early experience introducing its managed Medicaid model in the Des Moines, Iowa, market. It also provides an update on the Memphis program discussed in the (A) case.

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  • Harvard Business School Case 717-500


On November 11, 2016, Xi Dan, Senior Vice President of Tencent, and Ma Yongwu, Dean of Tencent Academy, were discussing how Tencent could develop new capabilities to sustain its growth miracle and entry into new technologies, expansion into B2B businesses, and internationalization.

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  • Harvard Business School Case 717-473

Facebook Fake News in the Post-Truth World

No abstract available.

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