NEW YORK (AP) -- About 1,000 graduate assistants started striking against New York University on Wednesday over its refusal to bargain with or recognize their union.It was unclear how many students were affected, but citing Wednesday as an example NYU spokesman John Beckman said of 2,700 classes, 165 were taught by graduate assistants.At a picket line in front of an NYU library in the city's Greenwich Village neighborhood, striking assistants and supporters chanted: "What do we want? Contracts. When do we want it? Now!"The Graduate Students Organizing Committee said its members would stay on strike until the university decides to bargain with them "in good faith." The assistants will not teach, grade, advise students or do research while on strike, they said."The students that I have in my class have been very supportive," said Kari Evanson, a teaching assistant in the French department. "We've tried everything else. This really was the last resort. ... I'm ready to fight."NYU says graduate assistants are not employees, but are students who have "assistantship" semesters as part of their financial aid packages of some $50,000 that includes free tuition."Any disruption to our students' education, even a minor one, is lamentable," NYU said in a statement.The graduate assistants had been represented by Local 2110 of the United Automobile Workers from 2000 until August of this year. NYU said then it would no longer recognize the union based on a policy reversal by the National Labor Relations Board on private universities allowing graduate student workers to unionize.The strike came after a delegation of professors failed to make headway Tuesday in urging NYU President John Sexton to negotiate.Holding up a sign that read "Nerds: working to make NYU even smarter," Kristin Ross, professor of comparative literature, said she would hold classes off campus in solidarity with the graduate students."I believe in their self-determination," she said. "My undergraduates are very, very interested in this whole process. It's integrated into their thinking."Copyright 2005 The Associated Press. All rights reserved.This material may not be published, broadcast, rewritten, or redistributed.