Applications are sifted through fine screen at Bates College, Maine

Outside, the snow falls gently on the wooded New England campus. Inside, seven pairs of hands rise decisively. Each hand has only one or two fingers extended. No clenched fist. It is a low score. Applicant admitted.

Blackball session for an undergraduate fraternity or sorority? Not at Bates College, a private coeducational school of some 1,430 students. The school has not allowed fraternities or sororities since it opened its doors in 1855.

The raised hands belong to the seven members of the admissions committee. They have just approved the application of a high school senior.

In the next three months the committee members will raise their hands some 2, 300 to 2,500 times. That is the expected number of applications they must winnow down to fill the 425 seats reserved for the class of 1988. (The hand and finger count works this way: Left hand rates academic record, right hand rates nonacademic record. One finger is tops; five is worst. A score of five or less from each committee member is usually the cutoff. A closed fist ''flags'' the application as a risk but worth further consideration.)

In the highly competitive world of college admissions at prestigious colleges , Bates is singled out as having one of the most refined acceptance procedures in the country. The director of admissions at one Ivy League campus acknowledges Bates as a standard-setter because of the thoroughness, care, and fairness of its student selection process.

While there are more than 2,200 institutions of higher learning in the United States, only some 50 have what could be considered competitive entrance requirements at the undergraduate level. The overwhelming majority of colleges - including almost all public colleges and universities - admit almost any student with a high school degree. Bates is one of a select group of some 30 colleges that reject at least two applicants for every one they accept.

Here, each application is read by 11 people: four faculty members from the sciences and humanities in addition to the seven-member admissions panel. Three members of the admissions staff give an application at least three ''read-throughs'' - and sometimes as many as 18 - before making a final decision , says William C. Hiss, dean of admissions and financial aid.

On this midwinter afternoon the seven committee members, three faculty members, and one reporter sit cramped around two tables in a side office of the admissions department. On the tables are the folders of 11 students. Reams of computer printouts cover the tables, piling up like snowdrifts in the Maine countryside.

But the selection process is not a line-up-the-ducks-and-shoot-them-down affair.

''We have to know our strengths as an institution; we must represent ourselves fairly to candidates,'' Dean Hiss says. ''This is the unquantifiable art to admissions. It is part of the process that defines what type of institution we are.''

The committee is very concerned about how well students do once they attend Bates. If more than a very small number were to fail, it would reflect unfavorably on their professional judgment - especially with such a large number of qualified applicants to choose from.

''There's a triage of credentials we look at,'' he explains. The top element is a student's high school transcript, by far the most important document. Grades, class rank, grade-point average, of course. But they also look very closely at the kind of courses taken and the kind of school attended, Hiss says. ''We like to see AP (advanced placement) or honor classes on a transcript.''

The next application on the table shows a record of mostly C's with some B's for the first two years. The junior year is outstanding, almost straight A's, low 500s on the SATs. ''A potential late bloomer,'' says Hiss. But when the course selection for the first semester of the senior year is brought up, with only three academic courses and no sciences, it is a unanimous reject.

''We look to see if there is a senior slump, where a student slacked off and took easy courses,'' assistant admissions Dean Sue Tree says. ''Selective schools don't have to take that kind of risk.''

Bates keeps a nine-year record of all previous applicants from a given high school. The committee knows how many students it accepted and rejected from that school. And it knows, of course, how well a student did once here. Using these data, the committee might hesitate to accept anyone below the top 5 percent of a class from some schools; with other schools, it might go down to the middle of the class for a candidate.

Hiss is bothered by the strong recommendation a guidance counselor has given the last applicant. The student's record, as set down in his application, didn't seem to warrant the counselor's action. ''He should know better than that with us,'' he says, making a note to call the counselor in the morning. ''Credibility is crucial when we are down to the last 500 candidates for those 425 seats. That's where we agonize.

''We don't hesitate to get on the phone and call a guidance officer, a teacher, or the student himself, if we feel we need more information,'' Hiss says.

After grades and courses, the next things weighed are test scores - the Scholastic Aptitude Test (SAT) and achievement tests. Then, what kinds of extracurricular activities did a student participate in? Did he or she come for an interview? How did it go? Also considered is the quality of writing on the application and in the letters of recommendation from high school faculty.

''I can't emphasize enough how seriously we take the writing,'' says Hiss. ''There are four faculty members who read the applications with us. The ability to write good critical prose is a keystone of every good college or university. The faculty members will say, 'If these people do not write well on their applications, on the essay that is part of the application, what are the odds of their doing so in their college courses?' ''

One applicant has included a description of a high school physics project - and how it changed his view of learning. Each student received 250 toothpicks and some glue and was told to build a model bridge. The bridge that could support the most weight got an A. This student's bridge - which he sent along with his application - can support 286 pounds. He is accepted.

Next folder.

It comes from what New England college admissions officials refer to as ''the gold coast'' - Fairfield County in western Connecticut. With one of the highest per capita incomes of any county in the US, that postmark usually means the student's parents are rich. Since tuition at Bates is $11,500 a year, plus another $1,000 for books, clothes, and traveling back and forth during breaks, does family wealth play a part in the process?

Definitely not, Hiss says.

''As fatuous as this may sound given such high figures, don't worry about the money. We funded all but 50 students over the last five years. We funded 97-98 percent of the students that needed it. Not untypical for good colleges with solid endowments. Select the school you want to go to and get in. The financial package - a loan, a campus job, scholarship, or grant - will fall into place.''

And before students get the feeling that most of the admissions process is in the hands of someone else, ''they should keep in mind that in many ways they have preselected themselves,'' says Hiss. This process starts almost 18 months before the folder winds up on the table.

There are five distinct decisions students make: whether to go to college; whether to inquire about a particular college; whether to visit the campus (something all good colleges strongly recommend); whether to apply; and finally whether to enroll.

Bates's admissions staff tries to spend an hour interviewing each candidate. ''You can find out quite a bit about a young person in that amount of time, one on one,'' says assistant dean Elizabeth Woodcock.

There's a final set of factors that work into the admissions process. In and of themselves, these don't determine acceptance or rejection, but at Bates they can be the ''tippers.'' They include things like minority status, geographic diversity, whether the student says Bates is his No. 1 choice, whether a relative went here.

The 11th and last application of the afternoon comes up for a vote. Two fists are raised out of the seven pairs of hands - the committee wants more information before making a final decision. On April 15, the date most colleges send out acceptance or rejection notices, this Bates College candidate, whether or not he gets in, can rest assured his application has received a thorough, evenhanded deliberation.