Responding to a mixture of strong student pressure and a pledge made last spring, the Economics Department's senior faculty voted Tuesday to appoint a Marxist graduate student, William H. Lazonick, to an assistant professorship in Economics. Lazonick's appointment will formally begin on July 1, 1975 and run for five years--the maximum amount of time possible for a non-tenured position.

Although the November report of the Visiting Committee of the Board of Overseers--which questioned the Ec Department for its failure to have more than one radical on its faculty--and the recent resignation of Wassily W. Leontief, Lee Professor of Economics, put more pressure than ever on the department, the commitment to hire one radical junior faculty member was made last April.

At that time, the Economics faculty agreed to a compromise over the recommendations presented by a curriculum committee, chaired by Kenneth J. Arrow, Conant University Professor, which had proposed the hiring of two radical instructors for this year. The faculty voted, instead, to "place first priority" on the hiring of one radical instructor for the 1975-76 academic year.

Last April the promise smacked of mere rhetoric--radical graduate students in the department insisted that the "compromise" was no compromise at all, but simply a way of giving lip-service to the hiring of radical faculty and the teaching of Marxian economics while discreetly refusing to take any action in either area.

Sources in the department, however said this week--in the aftermath of Lazonick's appointment--that conservative senior faculty, particularly James S. Duesenberry, chairman of the department, had indeed taken the pledge seriously.

Karl E. Case head tutor in Economics, said yesterday. "For the past year. Duesenberry has had every intention of getting the department a Marxist junior faculty member. The lack of any action has been causing the department embarrassment after embarrassment."

Still, the hiring very likely is only half a loaf for the radical graduate students and their one tenured faculty ally--Stephen A. Marglin '59, professor of Economics. Case said this week, "If Sam Bowles--the best Marxist economist in the country--couldn't get tenure. I don't think Lazonick will get tenure either."