How is the college admissions process like baseball? Consider two key statistics.

Baseball fans are obsessed with batting averages. They know the math: Hits divided by number of times at bat. There are a few nuances. Walks and sacrifices don’t count as at-bats. Ditto if a batter is hit by a pitch or awarded first base on catcher interference. The at-bat count follows rules that are universally recognized. Fans know, without question, that one player’s batting average is comparable with another’s. As of Tuesday morning, Detroit Tigers slugger Miguel Cabrera led the major leagues with a batting average of .350.

College-bound students obsess over admission rates. They, too, know the math: Number of students offered admission to a school’s entering first-year class divided by the total number of applicants. They know that low admission rates translate to selectivity and desirability in the hotly competitive market. As of this month, the U.S. Naval Academy had the lowest admission rate among national liberal arts colleges ranked by U.S. News & World Report: 6.8 percent for the class that entered in 2012.

But here is where college admissions is not like baseball.

There is no universally recognized rule for the definition of “applicant.” There is a federal definition with built-in wiggle room, there is a very similar guideline for reporting to market analysts, there are interpretations — but no hard-and-fast rules. That means college-bound students cannot really know whether one school’s admission rate is comparable with another’s.

All of this bears on the admission rate at Washington and Lee University in Lexington, Va. As The Washington Post reported this week, the school’s rate was 19 percent in the official tally for last fall’s entering class, or 24 percent if you don’t include more than 1,100 students whose applications were deemed incomplete.

University officials defend their official tally but have begun an internal review of their data-reporting process to address any questions about it. They also emphasize that students with incomplete application files are sometimes admitted and that plenty of other colleges include incompletes in their official totals. (Not all do. The University of Virginia, Harvey Mudd College and Wellesley College, for example, say they count only complete applications. And some colleges have recently revised their counting procedures to exclude incompletes.)

Now, back to the Naval Academy.

In December 2011, The Post reported that the academy included several thousand applications in its total count that were never completed. Among them were thousands of applications for what is known in Annapolis as the “Summer Seminar” — a six-day event for teenagers who want to learn more about the academy between their junior and senior years in high school.

The academy says the application for the seminar makes clear that it doubles as an preliminary application for the academy itself.

Here’s the federal definition of an applicant:

“An individual who has fulfilled the institution’s requirements to be considered for admission (including payment or waiving of the application fee, if any) and who has been notified of one of the following actions: admission, nonadmission, placement on waiting list, or application withdrawn by applicant or institution.”

Fulfilling requirements would seem to imply completeness — doing everything, including sending in test scores and any other information that is publicly described as a requirement. But notice that the definition does not explicitly rule out incomplete applications. So whether an applicant has fulfilled requirements to be considered is a judgment call. There is wide room for interpretation.

Here’s the academy’s view, according to Cmdr. John Schofield, a spokesman:

“Each application that is submitted for admission to the Naval Academy is an actionable application. The Naval Academy uses multiple tools in its admissions process that are designed to improve efficiency in the process as well as provide early notification to applicants who will not be admitted.”

This includes any Summer Seminar applicants who might skip all of the other steps that are required to complete an application.

“The application filled out by students for Summer Seminar states clearly that it is also the preliminary application, and students are told not to submit a separate preliminary application for admission,” Schofield said.

However, the academy recently did make an adjustment to its counting procedure. It eliminated Reserve Officers Training Corps candidates who did not indicate a specific interest in attending Annapolis. That helped shrink its applicant pool modestly.

Or, to return to the baseball analogy, that change weeded out some of the academy’s at-bats. And it changed the math. Of course in the admissions game, the lower a school’s “batting average” (i.e. admission rate) , the higher its selectivity.

The admission rate for the class that entered Annapolis this year will be about 8 percent — which will still be plenty low enough to qualify among the “league leaders” in selectivity for those who insist on keeping score despite the wild variability underlying the statistic.

Bruce Fleming, an English professor at the academy who is an in-house critic on this issue, said that subtracting those ROTC bids from the academy pool is not nearly enough. He says the academy ought to count only applicants who fulfill every requirement to be considered — and not count those students who just take the first step. That would push the academy’s admissions rate well into double digits.

“They have not addressed the fundamental process of misleading the American taxpayers, who fund the entire school,” Fleming said. “I feel adamant about this.”

Said Schofield: “The Naval Academy is committed to transparency in the admissions process.”