New physicians: a natural experiment in market organization

To select suitable supplier for complex equipment military-civilian collaborative design based on fuzzy preference information that from matching perspective

Combine complex equipment collaborative development in military-civilian integration context not only fulfils actual development requirement, but also beneficial to the national economy. Design procedure as first stage of complex equipment military-civilian collaborative development process, select suitable design supplier is significant to whole development process of complex equipment. In order to select suitable design supplier for complex equipment, two aspects done in this paper. One is comprehensive analysis of evaluated influencing factors that affect complex equipment military-civilian collaborative design process, corresponding evaluation indicator constructed and a combination of grey correlation, entropy, DEMATEL (Decision-making Trial and Evaluation Laboratory) and VIKOR analysis theory to obtain grey entropy-DEMATEL-VIKOR, then the combined method is utilized to acquire matching attributes for followed research content. Meanwhile, satisfaction degree for matching side obtained with the help of information aggregation based on power generalized Heronian mean which on the basis of fuzzy preference information. Then, through constructed matching model, suitable design supplier obtained. Finally, a corresponding illustrative example given.

An empirical evaluation of Chinese college admissions reforms through a natural experiment

While college admission decisions impact the educational experiences and labor market outcomes for millions of students each year, the best method to determine admissions has been vigorously debated by academics and policymakers across the globe. Driving this debate are a number of major theoretical and practical innovations over the past 2 decades. Using a natural experiment from China, we evaluate the performance of the immediate acceptance mechanism, used for many years for college admissions in China and school choice in the United States, and the newer parallel mechanism. We find that when provinces move to the parallel mechanism, students apply to more colleges and list more prestigious colleges first. We further find that the student–college matchings become more stable.

College admissions policies affect the educational experiences and labor market outcomes for millions of students each year. In China alone, 10 million high school seniors participate in the National College Entrance Examination to compete for 7 million seats at various universities each year, making this system the largest centralized matching market in the world. The last 20 y have witnessed radical reforms in the Chinese college admissions system, with many provinces moving from a sequential (immediate acceptance) mechanism to some version of the parallel college admissions mechanism, a hybrid between the immediate and deferred acceptance mechanisms. In this study, we use a natural experiment to evaluate the effectiveness of the sequential and parallel mechanisms in motivating student college ranking strategies and providing stable matching outcomes. Using a unique dataset from a province that implemented a partial reform between 2008 and 2009, we find that students list more colleges in their rank-ordered lists, and more prestigious colleges as their top choices, after the province adopts the parallel mechanism in its tier 1 college admissions process. These listing strategies in turn lead to greater stability in matching outcomes, consistent with our theoretical prediction that the parallel mechanism is less manipulable and more stable than the sequential mechanism.

"Almost-stable" matchings in the Hospitals / Residents problem with Couples

The Hospitals / Residents problem with Couples (hrc) models the allocation of intending junior doctors to hospitals where couples are allowed to submit joint preference lists over pairs of (typically geographically close) hospitals. It is known that a stable matching need not exist, so we consider min bp hrc, the problem of finding a matching that admits the minimum number of blocking pairs (i.e., is "as stable as possible"). We show that this problem is NP-hard and difficult to approximate even in the highly restricted case that each couple finds only one hospital pair acceptable. However if we further assume that the preference list of each single resident and hospital is of length at most 2, we give a polynomial-time algorithm for this case. We then present the first Integer Programming (IP) and Constraint Programming (CP) models for min bp hrc. Finally, we discuss an empirical evaluation of these models applied to randomly-generated instances of min bp hrc. We find that on average, the CP model is about 1.15 times faster than the IP model, and when presolving is applied to the CP model, it is on average 8.14 times faster. We further observe that the number of blocking pairs admitted by a solution is very small, i.e., usually at most 1, and never more than 2, for the (28,000) instances considered.

Incentives in Large Random Two-Sided Markets

Many centralized two-sided markets form a matching between participants by running a stable matching algorithm. It is a well-known fact that no matching mechanism based on a stable matching algorithm can guarantee truthfulness as a dominant strategy for participants. However, we show that in a probabilistic setting where the preference lists on one side of the market are composed of only a constant (independent of the size of the market) number of entries, each drawn from an arbitrary distribution, the number of participants that have more than one stable partner is vanishingly small. This proves (and generalizes) a conjecture of Roth and Peranson [1999]. As a corollary of this result, we show that, with high probability, the truthful strategy is the best response for a random player when the other players are truthful. We also analyze equilibria of the deferred acceptance stable matching game. We show that the game with complete information has an equilibrium in which, in expectation, a (1− o (1)) fraction of the strategies are truthful. In the more realistic setting of a game of incomplete information, we will show that the set of truthful stratiegs form a (1+ o (1))-approximate Bayesian-Nash equilibrium for uniformly random preferences. Our results have implications in many practical settings and are inspired by the work of Roth and Peranson [1999] on the National Residency Matching Program.

"What Program Directors Think" II: Results of the 2013 and 2014 Annual Surveys of the Association of Program Directors in Radiology

RATIONALE AND OBJECTIVES

The Association of Program Directors in Radiology (APDR) surveys residents' educational experiences, work responsibilities, and benefits to support radiology residency programs and their directors.

MATERIALS AND METHODS

This is an observational cross-sectional study using three Web-based surveys posed to the APDR membership in the spring of 2013 (March 7-29, 2013; 44 items), the fall of 2013 (October 24 to November 15, 2013; 36 items), and the spring of 2014 (March 3-21, 2014; 49 items) on the American Board of Radiology (ABR) Core examination, organization of Clinical Competency Committees (CCCs), fellowship match, and interventional radiology (IR)-diagnostic radiology (DR) training programs.

RESULTS

Responses were collected electronically, results were tallied using SurveyMonkey software, and qualitative responses were tabulated or summarized as comments. Findings were reported during the 60th and 61st annual meetings of the Association of University Radiologists, respectively. The maximal response rate was 35% in the spring 2013, 39% in the fall 2013, and 39% in the spring 2014.

CONCLUSIONS

With the ABR Core examination, radiology educators increasingly included multiple choice questions in teaching conferences. "Boards frenzy" was alive and well. The number of programs with a CCC was growing, chaired primarily by the Program Director (PD), with the most commonly used tool being the rotation evaluation. In view of "fellowship frenzy" in the third year of residency, only a minority of PDs were against a fellowship match in the National Resident Matching Program (NRMP). The majority of respondents replied that the new IR/DR pathway would negatively affect the DR residency.

The gastroenterology fellowship Match: how it failed and why it could succeed once again

The market for gastroenterology (GI) fellows adopted a centralized Match in 1986, and abandoned it in the late 1990s. We discuss why the Match initially was adopted, how and why it broke down, what differences this has made in the market for fellows, and what would be needed to restart the Match successfully. We assess the effects of the Match by comparing the GI fellows market now with when the Match was operating, and with the fellowship markets for internal medicine subspecialties that continue to use a Match. The breakdown of a well-functioning Match is rare, but may be caused by unusual shifts in market conditions, such as those experienced by gastroenterology in the late 1990s. The problems the gastroenterology Match originally was designed to solve re-emerged with the demise of the Match. The market has become more local and less national, than when there was a Match in place, and program recruitment of fellows occurs earlier and is more dispersed in time than internal medicine subspecialties that continue to use a Match. There is no evidence that the demise of the Match has had any effect on wages. The evidence strongly suggests that the Match could be reintroduced successfully, which would increase the mobility of potential GI fellows, allow potential fellows to compete for the widest range of programs, and allow programs to compete for the widest range of fellows.

The Nash equilibrium: a perspective

In 1950, John Nash contributed a remarkable one-page PNAS article that defined and characterized a notion of equilibrium for n- person games. This notion, now called the "Nash equilibrium," has been widely applied and adapted in economics and other behavioral sciences. Indeed, game theory, with the Nash equilibrium as its centerpiece, is becoming the most prominent unifying theory of social science. In this perspective, we summarize the historical context and subsequent impact of Nash's contribution.

Bias in computer systems

From an analysis of actual cases, three categories of bias in computer systems have been developed: preexisting, technical, and emergent. Preexisting bias has its roots in social institutions, practices, and attitudes. Technical bias arises from technical constraints of considerations. Emergent bias arises in a context of use. Although others have pointed to bias inparticular computer systems and have noted the general problem, we know of no comparable work that examines this phenomenon comprehensively and which offers a framework for understanding and remedying it. We conclude by suggesting that freedom from bias should by counted amoung the select set of criteria—including reliability, accuracy, and efficiency—according to which the quality of systems in use in society should be judged.

The relationship between National Resident Match Program rank and perceived performance in an emergency medicine residency

A nonconcurrent prospective cohort study was conducted to evaluate if National Resident Matching Program (NRMP) rank developed using multivariate regression followed by consensus group activity is associated with perceived general performance during emergency medicine residency. All residents graduating from a university hospital-based residency program between 1990 to 1993 were ranked by university faculty, private attendings, charge nurses, and a clerk. Each evaluator was asked to order (from the strongest to the weakest) a deck of cards that contained only each graduate's name and picture. NRMP ranks were scaled to adjust for differences in each year's match list length. Evaluators were unaware of the graduates NRMP ranks. Agreement among raters was analyzed using Kendall's coefficient of concordance. Perceived ranks were compared with actual NRMP ranks using the Spearman correlation procedure. Twenty graduates were evaluated by eight different individuals, yielding 160 pairs of ranks. There was moderately strong agreement among evaluators about the relative strength of the 20 residents (W = 0.67, P < .001). The association of perceived rank with NRMP rank was much greater than that expected by chance (r(s) = .35, P < .0001). Applicants with better NRMP ranks were perceived as stronger residents, which supports the strategy of using formal statistical modelling followed by consensus group activity as a method of generating NRMP rank lists.

Selection of emergency medicine residents

The selection of emergency medicine residents requires review of medical school performance and, usually, an interview in which applicants and program directors exchange important information. Computer technology is available to assist programs in the analysis of information about applicants. Ethnic diversity and minority recruitment should also be considered as 40% of all emergency medicine residencies have no minority residents. Suggestions for developing a valid, humane, and fair selection process are made.

The residency match in radiation oncology

Centralized matching of postgraduate training positions has been successfully implemented nationwide since 1951. Specialty and subspecialty matches have proliferated in the 1970's and early 1980's, and Radiation Oncology was the last residency program that did not have a centralized match arrangement. Responding to pressures from training program directors who were dissatisfied with the non-centralized matching of resident applicants, made especially acute by a rapid increase in the number of students interested in Radiation Oncology, the first centralized matching program for Radiation Oncology--the Radiation Oncology Matching Program (ROMP)--began in 1989. Two years of experience with the ROMP are summarized in this paper. Interest in training positions in Radiation Oncology remains high, with approximately 1.3 to 1.5 qualified applicants per each residency position. The major problem with the current arrangement in ROMP is lack of full participation. In 1989, approximately 70% of first year positions were offered through ROMP, and in 1990 this was closer to 60%. While the majority of programs desire and participate in a centralized match, participation at less than an 85 to 90% level will likely cause the centralized match to disband. Reasons for and against a centralized matching process and a history of matching programs in other specialties are discussed.

Smart Computer-Assisted Markets

The deregulation movement has motivated the experimental study of auction markets designed for interdependent network industries such as natural gas pipelines or electric power systems. Decentralized agents submit bids to buy commodity and offers to sell transportation and commodity to a computerized dispatch center. Computer algorithms determine prices and allocations that maximize the gains from exchange in the system relative to the submitted bids and offers. The problem is important, because traditionally the scale and coordination economies in such industries were thought to require regulation. Laboratory experiments are used to study feasibility, limitations, incentives, and performance of proposed market designs for deregulation, providing motivation for new theory.