Disadvantaged students are more likely to search for colleges haphazardly, rather than in the systematic way a good counselor would encourage. And that makes them more susceptible to marketing from lower-tier colleges that may not be a good fit, academically or financially. That’s the takeaway of a new paper that will be presented on Wednesday at the annual meeting of the American Educational Research Association but is not yet available online.

The paper, “Easy Targets: Haphazard College Searching and the Reproduction of Inequalities in Higher Education,” is based on a two-year qualitative study at two suburban high schools in the Northeast. Its author, Megan M. Holland, expects to receive her doctorate in sociology from Harvard University this month.

Among the 89 students she interviewed, Ms. Holland identified two main approaches to the college search. Some students were systematic, learning what different kinds of colleges had to offer and homing in on those that met a set of desired criteria they had developed over time. Other students conducted a haphazard search, often condensed and not intended to find colleges that matched desired criteria.

Academic achievement, race, and parents’ education level were all linked to the type of college search the students engaged in, Ms. Holland found. While 91 percent of high-achieving students searched systematically, only 8 percent of low-achieving students did. Among white students, 81 percent searched systematically; 24 percent of African-American students did. And 63 percent of students with at least one parent with a bachelor’s degree searched systematically, while 21 percent without a college-educated parent did.

That matters, the paper says, because students lacking a systematic approach were “much more influenced by the marketing efforts of colleges.”

When such students received marketing materials, they “enjoyed feeling wanted,” Ms. Holland said in an interview. By contrast, systematic searchers were skeptical of the materials, believing that “if colleges wanted them that much, it was a negative.”

Haphazard searchers were also more likely to respond to “snap apps,” applications for admission that can be filled out quickly and free, Ms. Holland observed. Some students attended admissions events where they could be accepted on the spot by less-selective colleges. And sometimes, students would hop on a school computer to learn about a college that had just admitted them that way.

As a result, by the time decision day rolled around, some students Ms. Holland followed had a number of acceptances but no viable options. That could lead some of them, she said, to enroll in colleges from which they would have very little chance of graduating.