By Paige Edmiston

> “Hmm, difficult. Very difficult. Plenty of courage, I see. Not a bad mind, either. There’s talent, oh yes. And a thirst to prove yourself. But where to put you?” > — The Sorting Hat, Harry Potter and the Sorcerer’s Stone (film)

This week, final-year medical students throughout the United States will gather in virtual settings reminiscent of banquet halls, eagerly awaiting the arrival of envelopes that will shape the next three to seven years of their professional lives. Occurring annually on the third Friday of March, Match Day serves as a profound rite of passage. It’s the moment when medical students discover where they will undergo their residency training, marking their transition from student-doctor to practicing physician.

These eagerly anticipated envelopes (or emails, during the pandemic) not only indicate their residency locations but also define their future specialties. Will they be surgeons in Chicago, or internists in Seattle?

This ceremony bears resemblance to the Sorting Hat from the Harry Potter series, which assigns new students to “Houses” at Hogwarts by discerning their true identities. Likewise, the Match Day envelope reveals the residency program that best aligns with each student's qualifications. While a computerized matching algorithm determines this pairing, many students believe their results reflect something more profound than mere calculations.

My first exposure to the matching algorithm came from my partner, now a first-year medical resident. Last year, he was among over 40,000 medical students, anxiously awaiting their match. I too felt the tension; though I wasn’t applying, the algorithm’s outcome affected my life as well. As the date approached, I transformed my anxious energy into academic curiosity. As a PhD candidate in anthropology examining digital technologies within the U.S. medical landscape, I pondered: What constitutes an “ideal” residency match?

In essence, how does the matching algorithm respond to the Sorting Hat’s pressing query: “But where to put you?”

Here’s a breakdown: After applying and interviewing at various programs within their chosen specialty (and backup options), students rank these programs according to what economists like Alvin Roth — who received the 2012 Nobel Prize for creating the matching algorithm — refer to as “true preferences.” The algorithm then analyzes these rankings, placing each student into the highest-ranked program that also reciprocates their preference.

For economists, this algorithm is a streamlined solution to the challenging issue of efficiently placing newly graduated medical students into residency programs.

However, for students, the matching algorithm, often called “the Match,” signifies something different. In the weeks leading to my partner’s Match Day, friends, family, and fellow students frequently reassured us that he would end up “where he was meant to be.”

These affirmations, depicting the Match as a tool of destiny, were not exclusive to our situation. A video from Stanford University’s Match Day, titled “A Day of Destiny for Medical Students,” illustrates this. It captures the countdown to the moment students across the nation can open their envelopes. The footage shows a banquet hall filled with tears and embraces as envelopes are opened, culminating in two sisters celebrating their acceptance into the same prestigious program, declaring, “As fate would have it, we are both going to UCSF [University of California, San Francisco]. … It was meant to be to stay together.”

While economists perceive the matching algorithm as a rational and efficient process, for students counting down the moments until they can unveil their envelopes, the Match embodies a more enigmatic and personal concept: fate. This interpretation of the algorithm as destiny is reinforced by the Match’s rules: if a student declines their assignment, they cannot reenter the process in the future.

Whether regarded as a hyper-efficient marketplace or a destiny-driven technology (or both), the matching algorithm can start to seem almost supernatural. Yet, unlike the Sorting Hat, algorithms are not magical. As anthropologist Nick Seaver notes, “Press on any algorithmic decision, and you will find many human ones.” The residency matching algorithm exemplifies this.

It’s clear how individual choices by students and program directors shape their rankings. To achieve the perfect match, students are tasked with the work of the Sorting Hat, delving into their “authentic” selves to determine which program represents the “best fit.” Program directors are similarly expected to do this for their institutions. However, upon deeper examination, the situation becomes more intricate. Preference lists are influenced by human choices that extend beyond individual desires.

Consider the adjustments made by the National Resident Matching Program (NRMP), which oversees the Match, to the algorithm in the 1980s. Participation in the Match was declining, raising concerns among NRMP leaders.

Roth attributed this drop to demographic shifts within medical schools: as more women entered the field, the number of medical school couples increased, and these couples often desired to reside in the same location. In a letter to The New England Journal of Medicine, a couple of medical students called on the NRMP to acknowledge the “unnecessary agony” of their situation, ultimately stating that “human agency is preferable to the machine here.” As a result, rather than participate in the Match and risk being placed in different locations, couples began negotiating directly with hospitals for positions.

By acting outside the Match to secure their placements, couples jeopardized the stability of the algorithm. The system relies on widespread participation; both students and programs must trust that the Match yields the best results. To restore confidence, the NRMP introduced a Couples Match option in 1984, allowing couples to submit joint preference lists to ensure they would be placed together.

Regardless of whether they opt for the Couples Match, students’ preference lists are influenced by their obligations to others and their social and economic contexts.

Does a student have a child who has recently made friends at school, or perhaps a parent needing care? Are they financially equipped to travel for interviews? If they’re part of a same-sex couple, will they feel comfortable relocating to a socially conservative area? Depicting the matching algorithm as the ultimate manifestation of an individual's true preferences overlooks the complex realities of decision-making within a community context.

Simultaneously, framing the matching algorithm as a fate-driven technology obscures how Match Day outcomes — like the entirety of a physician's career — are influenced by prevailing cultural notions of who constitutes a “good” doctor, often entangled with stereotypes surrounding race, ethnicity, class, age, and gender.

It is crucial to examine which individuals are prioritized in this process, as sociologist Ruha Benjamin emphasizes.

During residency interviews, medical students report being asked about their backgrounds, their spouses' professions, and family planning intentions. Despite NRMP guidelines prohibiting “discriminatory or coercive questions,” research indicates that “potentially discriminatory topics are frequently discussed during both formal and informal interview events across all medical specialties.”

In a society that perceives certain traits as more “doctor-like” than others, even seemingly innocuous inquiries, such as an applicant's hobbies, can shape how program directors view their suitability. It can be challenging to trace exactly how such questions impact any individual student's performance in the Match, especially when the ranking process is obscured by the neutral façade of an algorithm.

Nonetheless, as sociologist Ruha Benjamin suggests regarding technology design, it’s essential to interrogate which humans are prioritized in the process. This involves scrutinizing how social values and hierarchies influence the algorithm that supposedly determines ideal matches.

Anthropology provides a framework for reassessing the residency matching algorithm: it reveals that both students and program directors engaged in the Match are not merely rational agents but real individuals navigating the complexities of social life. Viewed through this lens, the Match is neither a flawlessly organized system nor an agent of fate; it is a complex interplay of human choices masked by computer-generated outcomes.

In summary, algorithms do not solely dictate what type of doctor a student will become; it is ultimately people who make that decision.

Paige Edmiston is a Ph.D. student in cultural anthropology at the University of Colorado, Boulder.

Originally published at www.sapiens.org on March 16, 2021.