hen most students in the Department of Operations Research and Financial Engineering at Princeton construct a senior thesis, they hew to studies of arcane derivatives, options and other financial instruments, some with an eye toward the potentially lucrative job market awaiting them on Wall Street.

Katherine L. Milkman, 22, decided to turn rigorous mathematical analytics on an even more mystical topic: the selection of short fiction for The New Yorker. In applying scientific metrics to an ineffable process, Ms. Milkman will no doubt set off a small, discreet tempest among a cadre of authors who would gladly saw off their (nonwriting) hand to be the next Jhumpa Lahiri, a young writer who won the Pulitzer Prize for fiction in 2000 for her book of short stories after her work was plucked from the pile by the editors at that weekly magazine.

Ms. Milkman, who has a minor in American studies, read 442 stories printed in The New Yorker from Oct. 5, 1992, to Sept. 17, 2001, and built a substantial database. She then constructed a series of rococo mathematical tests to discern, among other things, whether certain fiction editors at the magazine had a specific impact on the type of fiction that was published, the sex of authors and the race of characters. The study was long on statistics and short on epiphanies: one main conclusion was that male editors generally publish male authors who write about male characters who are supported by female characters.

The study's confirmation of the obvious left some wondering why Ms. Milkman, who graduates this morning from Princeton with high honors, went about constructing such an intricate wristwatch in order to tell the time, but others admire her pluck and willingness to cross disciplines in a way that wraps the left and right brain neatly into one project. Her adviser on the project, Prof. RenÈ Carmona, was thrilled by the concept and amazed by the resulting thesis.

"Katy had to completely design the project from scratch," he said. "She didn't collect the data, she created it and did a very rigorous quantitative analysis of all figures that she measured." She received an A-plus, her thesis won an American studies competition, and the current editor of New Yorker fiction, Deborah Treisman, found her work engaging, if not material to the task at hand.

"She gives you a new way of looking at these stories which would not have occurred to me," Ms. Treisman said. "Do I walk away thinking, `Now I have to think about gender and race and location in selecting stories?' No."

After harvesting the gossip about the tendentiousness of one editor or another ó there is much to choose from ó the thesis segues to the "Kolmogorov-Smirnov Two-Sample Goodness of Fit Test" and the "Pearson Correlation Coefficient Test."

"I was personally riveted by the whole thing," said Roger Angell, a writer at The New Yorker who worked as a fiction editor during part of the period scrutinized by Ms. Milkman. He spent a significant amount of time talking to Ms. Milkman and helped connect her with other people at the magazine. He was charmed by the results but worries they may sow confusion.

"Some unpublished writers are going to read this and say, `I now know what I have to do to get published in The New Yorker,' and it's not helpful in that way," he said. "In the end we published what we liked."

In applying numerically based analysis to literary matters, Ms. Milkman's work was something of a micro-execution of the controversial text-free literary investigations of Prof. Franco Moretti of Stanford, in which he examined the broad scope of literary history by the numbers, tracking the birth and denouement of various genres based on statistics. Longtime adherents to canonical literary thought were appalled by Professor Moretti's by-the-numbers approach to the study of literature, something Ms. Milkman came to be familiar with.

"Many people thought it was completely idiotic," she said. "But when they found out I would actually be reading the stories, they were more understanding."

The 116-page thesis is dense with footnotes and data addenda. (A CD-ROM of the data was appended in case someone is interested in testing her results.) The main inquiry is how a change in the head of the fiction department ó from Charles McGrath to Bill Buford ó affected the stories published in The New Yorker, perhaps the most sought-after real estate in the short fiction world. (A secondary question of whether a change in editor from Tina Brown to David Remnick had measurable effects came back a resounding no.)

In analyzing such matters, Ms. Milkman has brought statistical rigor to one of the more intense parlor games in the literary world. Critics have long suggested that under Mr. Buford ó who took over the magazine's fiction department in 1995 when Mr. McGrath came to The New York Times, and left to write books in 2002 ó female authors were about as welcome as they would be at the clubhouse of Augusta National.

According to Ms. Milkman, the number of male authors rose to 70 percent under Mr. Buford, compared with 57 percent under Mr. McGrath. She also found that Mr. Buford was much more likely to publish stories set in the New York area: the number of stories set in the mid-Atlantic region rose to 37 percent under Mr. Buford, compared with 19 percent under Mr. McGrath. The study also found that the first-person voice rose mightily under Mr. Buford, which may reflect the growth of memoir in the 90's more than anything else.

Under both editors the fiction in the magazine took as its major preoccupations sex, relationships, death, family and travel. Mr. Buford was relatively more interested in sex, a topic in 47 percent of the stories he published as opposed to 35 percent under Mr. McGrath. Mr. McGrath's authors tended to deal with one of the occasional consequences of that act, children, more frequently than Mr. Buford's writers: 36 percent under Mr. McGrath, 26 percent under Mr. Buford. (History, homosexuality and politics all tied for the attentions of Mr. Buford at a lowly 4 percent.)

"As a fiction editor, you are really on the receiving end of other people's agenda," Mr. Buford said. "You choose from what you are sent."

After a brief look at the study, he chose to see the glass as half full.

"The best thing that came out of it for me was not whether you could tell a difference," he added, "but that from beginning to end, the stories were good and fun to read."

Among Ms. Milkman's least shocking findings was that characters in New Yorker fiction tend to live in the same places New Yorker readers do, not the United States as a whole. (One could imagine if the same analytics were applied to New Yorker cartoons, where the Upper East Side is more robustly represented than all the middle places put together.)

In a conclusion that will probably cause few readers to spill their evening tea, she states that "quantitative analyses revealed that New Yorker characters are not representative of Americans or New York State residents in terms of their race."

"It is amazing and dazzling, and somewhat incomprehensible at some point," said Mr. McGrath, who left The New Yorker to edit The New York Times Book Review and is now a writer at large for the newspaper. "I think that it really suggests that it is best for editors not to think too much about what they do."

Ms. Milkman is by all accounts, including her own, a normal college student. Although she was once ranked in the Top 200 of junior tennis players in the United States, she set down the racket to devote more attention to various statistical investigations. But she still has time for other pursuits. She is a member of the Ivy eating club, the most notorious of Princeton's social clubs, renowned for its hard-drinking ways, and her teachers said she was a pleasure to deal with amid a scrum of careerist young students.

"She is pretty driven," said William Gleason, an associate professor of English and her American studies adviser. "But she is bright and eager, someone who likes to grab a topic and run with it, not just for the academic result ó which is grades in our world ó but because she is really curious."

Next fall she will attend Harvard Business School, seeking a doctorate in information technology and management.

"I wanted to do something that involved reading, and I read some amazing work," she said of her thesis. "Students tend to come up with a thesis that will trigger the interest of interviewers, but since Princeton grads don't have trouble getting jobs, that seemed sort of silly to me."