Alvin E. Roth

14 Results


The Need for (Long) Chains in Kidney Exchange

It is illegal in the U.S. and in most of the world to buy or sell organs for transplantation. Kidney exchange arises because a healthy person has two kidneys and can donate one to a person in need of a transplant. But a donor and his or her intended recipient may be incompatible. An incompatible patient-donor pair can exchange with another pair, or with more than one other pair, in a cycle of exchanges among patient-donor pairs that allows each patient to receive a kidney from a compatible donor. In addition, sometimes exchange can be initiated by an altruistic donor who does not designate a particular intended patient, and in that case a chain of exchanges need not form a closed cycle. This paper seeks to understand why such longer chains have become increasingly important in practical kidney exchange. The answer has to do with the growing percentage of patients for whom finding a compatible donor is difficult. These "highly sensitized" patients are those for whom finding a transplantable kidney is difficult, even from a donor with the same blood type, because of tissue-type incompatibilities. This paper shows that highly sensitized patients are the ones to benefit from longer cycles and chains, and that this does not harm low-sensitized patients. Read More

It’s Alive! Business Scholars Turn to Experimental Research

Business researchers are turning increasingly to experiments in the lab and field to unlock the secrets of what motivates CEOs, consumers, and policymakers. Closed for comment; 5 Comments posted.

Individual Rationality and Participation in Large Scale, Multi-Hospital Kidney Exchanges

As kidney exchange moves from local networks to a national level, a new set of problems arises. One central issue, for example, is how individual hospitals can be motivated to participate. This paper by Itai Ashlagi (Sloan School of Management, MIT) and Alvin E. Roth (Harvard Business School) provides a theoretical framework to study and overcome the kinds of problems that can be anticipated. Read More

Marketplace Institutions Related to the Timing of Transactions

Certain markets face the problem of "unraveling," in which competition for good talent leads a firm to make job offers earlier and earlier, without sufficient knowledge about any given applicant—and in which applicants are forced to decide whether to accept a job before they really know much about working for that firm. Harvard Business School professor Alvin E. Roth discusses how this issue affects the labor markets for new lawyers and gastroenterology fellows, as well as the market for postseason college football bowls. Read More

How to Fix a Broken Marketplace

Alvin E. Roth was a co-winner of the Nobel Prize in Economic Science this week for his Harvard Business School research into market design and matching theory. This article explores his research. Open for comment; 5 Comments posted.

Unraveling Results from Comparable Demand and Supply: An Experimental Investigation

In many professional labor markets, most entry-level hires begin work at around the same time: for example, soon after graduating from college or graduate or professional school. Despite a common start time, offers can be made and contracts can be signed at any time prior to the start of employment, sometimes well over a year before employment will begin. "Unraveling" happens in markets in which competition for the elite firms and workers is fierce, but the quality of workers may not be reliably revealed until after a good deal of hiring has already been completed. Thus unraveling is sometimes a cause of market failure, particularly when contracts come to be determined before critical information is available. In this paper Muriel Niederle of Stanford, Alvin E. Roth of HBS, and M. Utku Ünver of Boston College consider conditions related to supply and demand that tend to facilitate or mitigate unraveling. Read More

The Job Market for New Economists: A Market Design Perspective

How should the most appropriate employers and job candidates find each other? Newly minted economists typically send applications to an average of 80 potential employers, and as a result, many employers receive hundreds of applications. It is extremely time-consuming to sort through all the applications, and as the process unfolds, there is a risk of coordination failure, in which employers and candidates who would be well-suited do not manage to create a match. In this paper, HBS professors Peter A. Coles and Alvin E. Roth and colleagues provide an overview of the market for new PhD economists and describe new mechanisms to improve the matching process. They conclude by discussing the emergence of platforms for transmitting job market information, and other design issues that may arise in the market for new economists. Read More

How Economics May Lead to Better Football Games

When economists watch football games they see more than flying pigskin and stadiums overflowing with fans. In the case of U.S. college football, Harvard Business School professor Alvin E. Roth along with Guillaume R. Fréchette and M. Utku Ünver studied the timing of team selection for championship bowls. What they found: Good teams are much better matched up than they used to be, and there are implications beyond sports. Q&A with Al Roth. Read More

Unraveling Yields Inefficient Matchings: Evidence from Post-Season College Football Bowls

Many market institutions have evolved to coordinate the timing of transactions and to prevent them from taking place too early or at uncoordinated times. In the case of post-season college football games, called "bowls," during the early 1990s the determination of which teams would play in which bowls was often made with several games still remaining to be played in the regular season. Practically speaking, this meant that the teams with the best end-of-season records might not play one another, because at the time the matchings were determined it wasn't yet known which teams these would be. Over the last decade, however, this market has undergone a number of reorganizations that have delayed this matching decision until the end of the regular season. For this working paper, the authors used Nielsen rating data on television viewership and the AP sportswriters' poll of team rankings to show that, by matching later, the chance of matching the best teams has increased, and the result is an increase in television viewership. Read More

Repugnant Markets and How They Get That Way

Repugnance is different in different places and at different times, says Harvard economist Alvin E. Roth in this Q&A. As someone who designs and builds new markets, he marvels at how society decides whether a transaction is "good" or "bad"—even when such transactions are very much alike. Read More

Repugnance as a Constraint on Markets

While some kinds of transactions are repugnant at certain times and places, they are considered perfectly acceptable in other situations. This essay examines a wide range of examples, including the buying and selling of kidneys for transplantation. Repugnance has important consequences for the transactions and markets we see. Read More

Strategy-Proofness versus Efficiency in Matching with Indifferences: Redesigning the NYC High School Match

One of the goals of school matching systems is to limit the extent to which students and parents feel it necessary to "game the system" to be accepted at a favored school. Several years ago, the authors of this paper assisted the New York City Department of Education in redesigning the way it matched over 90,000 students entering public high schools each year. The situation in New York City is a hybrid: Some schools actively rank potential students, others have no preferences, and still others fall in between. This paper concentrates on the welfare considerations and incentives that arise in school choice due to the fact that many students are regarded by schools as equivalent. The research develops and expands on economic theory demanded by the design of school choice mechanisms. Read More

When Rights of First Refusal Are a Bad Deal

Contracts that include a right of first refusal usually benefit the holder of that right. But not always. New research by professor Alvin E. Roth and colleague Brit Grosskopf explains when it's wise to say no. Read More

Amazon, eBay and the Bidding Wars

"Sniping" is a popular way of winning a bid in the world of online auctions. But how far can it change the playing field? HBS professor Alvin Roth takes a look at how bidding rules change the way the game is played. Read More