%0 Journal Article %T Essential dimension of projective orthogonal and symplectic groups of small degree %A Sanghoon Baek %J Mathematics %D 2011 %I arXiv %X In this paper, we study the essential dimension of classes of central simple algebras with involutions of index less or equal to 4. Using structural theorems for simple algebras with involutions, we obtain the essential dimension of projective and symplectic groups of small degree. %U http://arxiv.org/abs/1111.4697v1