Artists, gallery owners and critics have a fairly easy time describing the realists. Consider what one of them said about Ford Maddox Brown's "Chaucer at the Court of Edward III" canvas: "If I didn't know better, I'd think that was a painting of Chaucer at the Court of Edward III." That's realism for you! On the other hand, it's not as simple when it comes to abstract expressionism. Consider the work of Luis Landa, whose show "Data Visualization" opens Saturday with a reception and artist's talk at 6 p.m. in New London's Expressiones Cultural Arts Center. Shown above, for example, is one of the pieces in Landa's exhibit. Not sure what it depicts but it's NOT Chaucer. Landa, a resident artist at Expressiones, says he's inspired by the various ways to quantify human behavior in society - and his art symbolically represents his own observations. Through April 18. Expressiones is at 84 Bank St. Hours 11 a.m.-5 p.m. Wed.-Fri., 10 a.m.-1 p.m. Sat.; (860) 501-9278.