FOR TIONA NEKKIA MCCLODDEN’S latest work, The Trace of an Implied Presence, currently on view at the Shed in New York, the artist has installed four dancefloors in the second-floor gallery, each tailored to different specifications. Two are covered in Marley (one black and one white). Two are made of hard wood. Suspended above each dancefloor is a screen, onto which are projected color and black-and-white filmed portraits of Black performers. Here McClodden presents Michael J. Love, a tap dancer and scholar, striking complex rhythms against the floor; Kim Grier-Martinez, current artistic director