Update: An earlier version of this story reported that at least five percent of colleges have become “substantially” less selective in recent decades. In fact, at least 50 percent have become less selective, according to the researcher.

As the number of high school graduates rose to a record high at the end of the decade, Ivy League colleges were reporting record-low acceptance rates, leading many to believe that the college admissions process was becoming more competitive than ever.

However, a recent paper by Stanford economics Prof. Caroline Hoxby, director of the Economics of Education Program for the National Bureau of Economic Research, pushes against this theory. Hoxby argues that most U.S. colleges are not more selective now than they were 50 years ago and that at least 50 percent of colleges have become substantially less selective.

In “The Changing Selectivity of American Colleges,” Hoxby calls this misconception — the perceived increase in competition — a consequence of people extrapolating from the experiences and acceptance rates of a small number of colleges, particularly schools in the Ivy League, Stanford, Duke and a handful of elite liberal arts colleges.

“These colleges have experienced rising selectivity, but their experience turns out to be the exception rather than the rule,” she wrote, adding that only the “top 10 percent of colleges are substantially more selective now than they were in 1962.”

Hoxby indicates that the selectivity of most colleges has been trending downward consistently since about 1950, explaining that although competition has increased for schools like Harvard and Stanford, it is now easier for students to get into a state college.

“A student now needs weaker preparation, lower test scores, etc., to be admitted to most colleges in the U.S.,” she wrote in an e-mail to The Daily.

“If you are the average student, you certainly should not be worrying about college admissions standards rising,” she said. “It is really only students who are at or above the 90th percentile in aptitude and achievement who should think about college selectivity rising.”

Hoxby believes, however, that the overall decrease in college selectivity has not been caused by falling demand for a college education. Rather, the supply of “college places” has risen faster. According to her research, the number of high school graduates has grown by 131 percent while the number of college spots has risen by 297 percent.

“There are many more students demanding a college education today than in the past, both because there are more people in the U.S. now and because college education is now more necessary for attaining a middle-class lifestyle,” she said.

Hoxby reasons that when supply grows faster than demand, selectivity is going to decrease.

In addition to supply-and-demand economics, she attributes the decrease in selectivity to a second phenomenon: “re-sorting.” She explains that students used to attend a local college regardless of their abilities or the school’s characteristics; now, however, students’ choices are driven less by proximity and more by a college’s resources and student body.

“Clearly, if high-aptitude students were now more determined to attend selective colleges and less concerned about attending local colleges…the initially more-selective colleges would become more selective and initially less-selective colleges would become less selective,” she said.

In its recent early admission cycle, Stanford’s 13.5 percent admit rate for early action applicants from the Class of 2014 actually represented an increase in the number of students accepted from the previous year, when the University accepted 12.8 percent of early applicants — a seeming exception to Hoxby’s theory.

However, Hoxby maintains that these numbers are “meaningless” in explaining trends in selectivity.

“If students who applied to Stanford early have better scores and grades than in previous years, the admissions office should have accepted a higher share of them,” she said. “The fact that more were accepted says nothing about selectivity. You have to look at an absolute standard of selectivity (scores, grades, other qualifications). You cannot look at acceptance ratios and expect to get the answer right.”