Matina Horner, as a graduate student at the University of Michigan, as a professor of Psychology and Social Relations here, and as president of Radcliffe College, has been obsessed with theories involving sex differences in achievement performance.

In works covering an eight-year period, Horner has identified a syndrome to which she says only women fall prey--that is, the motive to avoid success.

Another Harvard social scientist, David C. McClelland, professor of Psychology, this week jumped on the "women-are-afraid-to-succeed" bandwagon. He says that a report he has prepared categorically shows that women's fear of success rises in their four years at Radcliffe, while their male counterparts' fear declines.

McClelland said yesterday that even though he is not sure how his study measures fear of success, he is certain of his results, which corroborate the Horner thesis.

McClelland's findings are part of a massive as-yet-unpulished study being prepared in conjunction with the Office of Tests and Evaluation.

Dean K. Whitla, the office's director, said yesterday that the study will assess the impact of undergradute education among students at Harvard.

When asked yesterday why the part of the report dealing with women's fear of success was made public, while the rest remained secret, McClelland said, "Women are oppressed because undergraduate men are pigs. We have to publicize this, and to let faculty, administrators and students see that they're acting terribly."

But some members of the faculty, as well as some students and administrators, say that studies such as McClelland's, in which variables and measures are defined rather loosely, only succeed in adding fuel to the hardline attitudes involving women prevalent among illustrious members of the Harvard community.

Critics of the fear-of-success theory say that women do not avoid success, but rather failure. The McClelland and Horner thesis, they say, is inexact in distinguishing the difference.

For example, Judith Walzer, the director of the Office of Women's Education, said yesterday The Crimson story on the McClelland report presented an unbalanced view of women's situation here. "Radcliffe women," Walzer says, "fear falling flat on their faces and nothing else."

McClelland said he does not feel his theory lends credence to the argument of women's inferiority, but just documents women's oppression.

And although the social scientist readily admits that many Harvard faculty members feel teaching women is a "waste of time," he stressed that his report's findings will not exacerbate the already tenuous position of women here.