> spplot(beta, "1") Error in `[.data.frame`(as(obj, "data.frame"), zcol) : undefined columns selected I can't seem to fix this. Version: 0.9-10 THK -- Timothy H. Keitt, University of Texas at Austin Contact info and schedule at http://www.keittlab.org/tkeitt/ Reprints at http://www.keittlab.org/tkeitt/papers/ ODF attachment? See http://www.openoffice.org/