For at least two decades, older faculty members have fretted about a shrinking gap between junior and senior professors’ salaries on the tenure track – a phenomenon known as salary compression.

But at at least one major university, there is not much evidence of such compression across the last two decades, according to a paper presented here Monday during the annual meeting of the American Educational Research Association.

The study was presented by Sharon L. Weinberg, a professor of educational statistics and psychology at New York University. Ms. Weinberg previously served there as vice provost for faculty affairs. Her study does not name the university under analysis, but during the conference panel, she strongly hinted that it is NYU.

Ms. Weinberg looked at 20 cohorts of newly hired and promoted faculty members at the university, from those hired or promoted in 1986 to those hired or promoted in 2005. In each case, she compared the salaries of assistant professors in their first year to the salaries of professors during the first year of promotion to full professor.

(Like most other scholars who have looked at salary compression, Ms. Weinberg excluded lateral senior-faculty hires because such people are usually stars who can command impressive paychecks. Instead, she looked only at scholars promoted to full-professor status from within the institution.)

Across the 20 years of the study, Ms. Weinberg found, there was no reduction in the ratio between full-professor and assistant-professor salaries. On average, newly hired assistant professors earned roughly two-thirds of newly promoted full professors’ salaries throughout the period. If anything, the gap between the two groups’ salaries increased slightly over time, but that change was not statistically significant.

Nonetheless, Ms. Weinberg did cite possible evidence of an increase in salary compression in recent years. Early in this decade, she said, the university tried to improve the quality of its newly hired junior faculty by increasing its opening salaries. The 2003 and 2005 cohorts of new junior faculty came to the university with higher salaries but earned lower-than-average raises in subsequent years.

Ms. Weinberg said that her method – which looks at senior faculty members only in their first year at full-professor status – is an improvement on previous studies of salary compression. Studies that try to aggregate the salaries of all senior-faculty members can generate “very noisy data,” she said.—David Glenn