1. A device for graphical display of statistical effects of different conditions C.sub.i (i=1,. .. ,J) on a categorical or continuous outcome E, based on a matrix A associating observed outcomes E.sub.j (j=1,. .. ,J) with conditions C.sub.i, the device comprising: (a) matrix storage means for storing the values from Matrix A provided as an input; (b) calculating means for calculating, using a selected model, the slope of the linear plot of the relative likelihood .PSI..sub.j.i -.PSI..sub.j.0 as a function of a score Y.sub.j associated with each outcome E.sub.j for a given one of the conditions C.sub.i in relation to the given condition reference C.sub.0 and a given outcome reference E.sub.0 ; (c) output means for providing a graphical output plotting each .PSI..sub.j.i -.PSI..sub.j.0 as a function of y.sub.j for the given C.sub.i.