Alexander J. MacKay - Faculty & Research - Harvard Business School
Photo of Alexander J. MacKay

Alexander J. MacKay

Assistant Professor of Business Administration


Alexander MacKay is an assistant professor of business administration in the Strategy Unit. His research focuses on matters of competition, including pricing, demand, and market structure. Previously, he was a postdoctoral scholar at Harvard Business School and at Harvard Kennedy School.

Professor MacKay earned his Ph.D. in economics from the University of Chicago. Prior to his doctoral degree, he worked at a consulting firm that specialized in the design and analysis of business experiments. He has a B.A. in economics from the University of Virginia.

Journal Articles
  1. The Long-Run Dynamics of Electricity Demand: Evidence from Municipal Aggregation

    Tatyana Deryugina, Alexander MacKay and Julian Reif

    We study the dynamics of residential electricity demand by exploiting a natural experiment that produced large and long-lasting price changes in over 250 Illinois communities. Using a flexible difference-in-differences matching approach, we estimate that the price elasticity of demand grows from -0.09 in the first six months to -0.27 two years later. We find similar results with a dynamic model in which usage is a function of past and future prices. Our findings highlight the importance of accounting for consumption dynamics when evaluating energy policy.

    Keywords: electricity demand; consumption dynamics; Energy; Policy; Demand and Consumers; Price; Mathematical Methods;

    Citation:

    Deryugina, Tatyana, Alexander MacKay, and Julian Reif. "The Long-Run Dynamics of Electricity Demand: Evidence from Municipal Aggregation." American Economic Journal: Applied Economics 12, no. 1 (January 2020): 86–114.  View Details
  2. Bias in Reduced-form Estimates of Pass-through

    Alexander MacKay, Nathan H. Miller, Marc Remer and Gloria Sheu

    We show that, in general, consistent estimates of cost pass-through are not obtained from reduced-form regressions of price on cost. We derive a formal approximation for the bias that arises even under standard orthogonality conditions. We provide guidance on the conditions under which bias may frustrate inference.

    Keywords: pass-through; reduced-form aggression; bias;

    Citation:

    MacKay, Alexander, Nathan H. Miller, Marc Remer, and Gloria Sheu. "Bias in Reduced-form Estimates of Pass-through." Economics Letters 123, no. 2 (May 2014): 200–202.  View Details
  3. Challenges for Empirical Research on RPM

    Alexander MacKay and David A. Smith

    This article discusses the empirical challenges that researchers face when demonstrating the existence and effects of resale price maintenance (RPM). We outline three approaches for finding price effects of RPM and the corresponding hurdles in data and methodology. We show that the quantity test that was suggested by Posner (1977; 1981) does not identify the change to welfare when demand-enhancing effects are considered generally. Finally, we present some solutions to the challenge of identifying welfare effects, and we suggest guidelines for future research.

    Keywords: antitrust issues and policies; antitrust law; resale price maintenance; welfare economics; Price; Competition; Research;

    Citation:

    MacKay, Alexander, and David A. Smith. "Challenges for Empirical Research on RPM." Review of Industrial Organization 50, no. 2 (March 2017): 209–220.  View Details
Working Papers
  1. Recovering Investor Expectations from Demand for Index Funds

    Mark Egan, Alexander J. MacKay and Hanbin Yang

    We use a revealed-preference approach to estimate investor expectations of stock market returns. Using data on demand for index funds that follow the S&P 500, we develop and estimate a model of investor choice to flexibly recover the time-varying distribution of expected returns. Our analysis is facilitated by the prevalence of “leveraged” funds that track the same underlying asset: by choosing between higher and lower leverage, investors trade off higher return against less risk. Although generated from a different method (realized choices) and a different population, our quarterly estimates of investor expectations are positively and significantly correlated with the leading surveys used to measure stock market expectations. Our estimates suggest that investor expectations are heterogeneous, extrapolative, and persistent. Following a downturn, investors become more pessimistic on average, but there is also an increase in disagreement among participating investors.

    Keywords: stock market expectations; demand estimation; exchange-traded funds (ETFs); Demand and Consumers; Investment; United States;

    Citation:

    Egan, Mark, Alexander J. MacKay, and Hanbin Yang. "Recovering Investor Expectations from Demand for Index Funds." NBER Working Paper Series, No. 26608, January 2020. (Direct download. Harvard Business School Working Paper, No. 20-122, May 2020)  View Details
  2. Competition in Pricing Algorithms

    Zach Y. Brown and Alexander MacKay

    Increasingly, retailers have access to better pricing technology, especially in online markets. Through pricing algorithms, firms can automate their response to rivals’ prices. What are the implications for price competition? We develop a model in which firms choose algorithms, rather than prices. Even with simple (i.e., linear) algorithms, competitive equilibria can have higher prices than in the standard simultaneous Bertrand pricing game. Using hourly prices of over-the-counter drugs from five major online retailers, we document evidence that these retailers possess different pricing technologies. In addition, we find pricing patterns consistent with competition in pricing algorithms. A simple calibration of the model suggests that pricing algorithms lead to meaningful increases in markups, especially for firms with superior pricing technology.

    Keywords: pricing; algorithms; Price; Technology; Competition;

    Citation:

    Brown, Zach Y., and Alexander MacKay. "Competition in Pricing Algorithms." Harvard Business School Working Paper, No. 20-067, November 2019. (Revised April 2020. Direct download.)  View Details
  3. Consumer Inertia and Market Power

    Alexander MacKay and Marc Remer

    We study the pricing decision of firms in the presence of consumer inertia. Inertia can arise from habit formation, brand loyalty, switching costs, or search, and it has important implications for the interpretation of equilibrium outcomes and counterfactual analysis. In particular, consumer inertia affects the scope of market power. We show that the effects of competition on prices and profits are non-monotonic in the degree of inertia. Further, a model that omits consumer inertia tends to overstate the marginal effect of competition on price, relative to a benchmark that accounts for consumer dynamics. We develop an empirical model to estimate consumer inertia using aggregate, market-level data. We apply the model to a hypothetical merger of two major retail gasoline companies, and we find that a static model predicts price increases greater than the price increases predicted when accounting for dynamics.

    Keywords: consumer inertia; market power; dynamic competition; demand estimation; Consumer Behavior; Markets; Performance; Competition; Price;

    Citation:

    MacKay, Alexander, and Marc Remer. "Consumer Inertia and Market Power." Harvard Business School Working Paper, No. 19-111, April 2019. (Direct download.)  View Details
  4. Estimating Models of Supply and Demand: Instruments and Covariance Restrictions

    Alexander MacKay and Nathan H. Miller

    We consider the identification of empirical models of supply and demand. As is well known, a supply-side instrument can resolve price endogeneity in demand estimation. We show that, under common assumptions, two other approaches also yield consistent estimates of the joint model: (i) a demand-side instrument or (ii) a covariance restriction between unobserved demand and cost shocks. The covariance restriction approach can obtain identification even the absence of instruments. Further, supply and demand assumptions alone may bound the structural parameters. We develop an estimator for the covariance restriction approach that is constructed from the output of ordinary least squares regression and performs well in small samples. We illustrate the methodology with applications to ready-to-eat cereal, cement, and airlines.

    Keywords: demand estimation; identification; endogeneity bias; covariance restrictions; ordinary least squares; instrumental variables;

    Citation:

    MacKay, Alexander, and Nathan H. Miller. "Estimating Models of Supply and Demand: Instruments and Covariance Restrictions." Harvard Business School Working Paper, No. 19-051, October 2018. (Revised October 2019. Direct download.)  View Details
  5. Contract Duration and the Costs of Market Transactions

    Alexander MacKay

    The optimal duration of a supply contract balances the costs of reselecting a supplier against the costs of being matched to an inefficient supplier when the contract lasts too long. I develop a structural model of contract duration that captures this tradeoff and provide an empirical strategy for quantifying (unobserved) transaction costs. I estimate the model using federal supply contracts for a standardized product, where suppliers are selected by procurement auctions. The estimated transaction costs are substantially greater than consumer switching costs and a significant portion of total buyer costs. Counterfactuals illustrate the importance of accounting for the duration margin.

    Keywords: vertical relationships; transaction costs; contract duration; auctions; identification; Supply Chain; Cost; Contracts; Auctions; Mathematical Methods;

    Citation:

    MacKay, Alexander. "Contract Duration and the Costs of Market Transactions." Harvard Business School Working Paper, No. 18-058, December 2017. (Revised May 2020. Direct download.)  View Details
Cases and Teaching Materials
  1. Uber: Competing Globally

    Alexander J. MacKay, Amram Migdal and John Masko

    This case describes Uber’s global market entry strategy and responses by regulators and local competitors. It details Uber’s entry into New York City (New York), Bogotá (Colombia), Delhi (India), Shanghai (China), Accra (Ghana), and London (United Kingdom). In each instance, the case includes information about Uber’s strategy in that market, existing regulations on taxis and transportation in each market, the reactions of competitors and regulators, and regional information. The case allows for instruction related to competitive strategy, global expansion, nonmarket strategy, regulation, market economics, supply restrictions, and related topics.

    Keywords: Business Ventures; Business Growth and Maturation; Business Model; Geography; Geographic Location; Geographic Scope; Globalization; Global Strategy; Multinational Firms and Management; Globalized Markets and Industries; Governance; Governance Controls; Governing Rules, Regulations, and Reforms; Innovation and Invention; Disruptive Innovation; Innovation Strategy; Law; Management; Growth and Development Strategy; Growth Management; Markets; Demand and Consumers; Consumer Behavior; Network Effects; Emerging Markets; Market Design; Market Entry and Exit; Market Participation; Supply and Industry; Industry Structures; Planning; Strategic Planning; Relationships; Business and Community Relations; Business and Government Relations; Business and Stakeholder Relations; Labor and Management Relations; Networks; Strategy; Adaptation; Business Strategy; Competition; Competitive Advantage; Competitive Strategy; Expansion; Technology; Mobile Technology; Technology Platform; Transportation; Transportation Networks; Transportation Industry; Technology Industry; Africa; Ghana; Asia; China; Shanghai Shi; Shanghai; India; New Delhi; Europe; United Kingdom; England; London; Latin America; North and Central America; United States; New York (city, NY); New York (state, US); South America; Colombia;

    Citation:

    MacKay, Alexander J., Amram Migdal, and John Masko. "Uber: Competing Globally." Harvard Business School Case 720-404, April 2020.  View Details
  2. Choosing the Right Esports Business Model

    David Collis and Alexander MacKay

    Two esports entrepreneurs must choose on which business model to focus their time and money. After successfully launching an online esports coaching platform, a number of new opportunities emerge in the rapidly growing esports space that now has close to one billion gamers and an online audience that is greater than the Superbowl. Should they focus on a B2C business, a B2B business? Develop an analytics capability to support "sabremetrics" for esports or a content creation capability? How can they best exploit ownership of the world's top team in the "Hearthstone" league. The choice will depend on the future industry structure and how the two can most effectively "follow the money."

    Keywords: entrepreneurial ecosystems; business development; Business Ventures; Entrepreneurship; Business Model; Management; Strategy; Sports; Entertainment and Recreation Industry; Information Technology Industry; Media and Broadcasting Industry; Sports Industry; Video Game Industry; North and Central America; Europe; Asia;

    Citation:

    Collis, David, and Alexander MacKay. "Choosing the Right Esports Business Model." Harvard Business School Case 719-459, March 2019. (Revised March 2020.)  View Details
  3. Commonwealth Joe Coffee Roasters

    Alexander MacKay and Ramon Casadesus-Masanell

    At the end of 2016, the leadership team of Commonwealth Joe Coffee Roasters—Robert Peck, Chase Damiano, and Jeremy Martin—had begun an ambitious retail expansion strategy in the Washington, D.C. metropolitan area for their specialty coffee business. That October, they had opened their first custom-designed store in a brand-new luxury apartment building. The new store was an immediate success, even though a Starbucks had recently opened across the street. At the same time, a separate business line—selling cold brew coffee in kegs to office customers—had grown unexpectedly. Many new office accounts were added, even as the team promoted the new retail store. Now, as Peck, Damiano, and Martin prepared for the next capital raise, targeted for February 2017, they evaluated their strategy going forward. Should Commonwealth Joe stay with retail, or should they shift their strategy to focus on the office business?

    Keywords: cold brew coffee; specialty coffee; on-premise coffee market; retail expansion strategy; Entrepreneurship; Business Model; Brands and Branding; Expansion; Strategy; Decision Making; Food and Beverage Industry; Retail Industry;

    Citation:

    MacKay, Alexander, and Ramon Casadesus-Masanell. "Commonwealth Joe Coffee Roasters." Harvard Business School Case 719-451, December 2018. (Revised December 2019.)  View Details