OPTIONS NOCENTER; /* using model with TIME = 0, 1, 2, 4 and TIME^2 in the model UN working correlation */ PROC IML; print 'Using IML to compare estimated probabilities with observed proportions'; oprob = {.174 .268 .337 .490, .072 .189 .146 .200, .185 .186 .163 .240, .182 .187 .229 .256}; ologit = log (oprob / (1-oprob)); xmat = { 1 0 0, 1 1 1, 1 2 4, 1 4 16}; g1 = {-1 0 0}; /* Helmert contrast coefficients for Control group */ g2 = {.333 -1 0}; /* Helmert contrast coefficients for No-Show group */ g3 = {.333 .5 -1}; /* Helmert contrast coefficients for Tx1 group */ g4 = {.333 .5 1}; /* Helmert contrast coefficients for Tx2 group */ /* use separate race means */ raceavg = {.2936, .3474, .0581, .1538}; xg1 = xmat || xmat[,1]*g1 || xmat[,1]*raceavg[1] || xmat[,2]*g1; xg2 = xmat || xmat[,1]*g2 || xmat[,1]*raceavg[2] || xmat[,2]*g2; xg3 = xmat || xmat[,1]*g3 || xmat[,1]*raceavg[3] || xmat[,2]*g3; xg4 = xmat || xmat[,1]*g4 || xmat[,1]*raceavg[4] || xmat[,2]*g4; print 'Covariate matrix - Control group', xg1 [FORMAT=8.3]; print 'Covariate matrix - No-Show group', xg2 [FORMAT=8.3]; print 'Covariate matrix - Tx1 group', xg3 [FORMAT=8.3]; print 'Covariate matrix - Tx2 group', xg4 [FORMAT=8.3]; beta = {-1.014, -0.610, 0.130, 0.811, 0.366, 0.271, 0.353, -0.219, -0.073, -0.062}; elogitg1 = xg1*beta; elogitg2 = xg2*beta; elogitg3 = xg3*beta; elogitg4 = xg4*beta; eprobg1 = 1 / (1 + exp( - elogitg1)); eprobg2 = 1 / (1 + exp( - elogitg2)); eprobg3 = 1 / (1 + exp( - elogitg3)); eprobg4 = 1 / (1 + exp( - elogitg4)); elogit = elogitg1 || elogitg2 || elogitg3 || elogitg4; eprob = eprobg1 || eprobg2 || eprobg3 || eprobg4; print 'Observed logits - time by group', ologit [FORMAT=8.3]; print 'Observed probabilities - time by group', oprob [FORMAT=8.3]; print 'Estimated logits - time by group', elogit [FORMAT=8.3]; print 'Estimated probabilities - time by group', eprob [FORMAT=8.3]; Using IML to compare estimated probabilities with observed proportions Covariate matrix - Control group XG1 1.000 0.000 0.000 -1.000 0.000 0.000 0.294 0.000 0.000 0.000 1.000 1.000 1.000 -1.000 0.000 0.000 0.294 -1.000 0.000 0.000 1.000 2.000 4.000 -1.000 0.000 0.000 0.294 -2.000 0.000 0.000 1.000 4.000 16.000 -1.000 0.000 0.000 0.294 -4.000 0.000 0.000 Covariate matrix - No-Show group XG2 1.000 0.000 0.000 0.333 -1.000 0.000 0.347 0.000 0.000 0.000 1.000 1.000 1.000 0.333 -1.000 0.000 0.347 0.333 -1.000 0.000 1.000 2.000 4.000 0.333 -1.000 0.000 0.347 0.666 -2.000 0.000 1.000 4.000 16.000 0.333 -1.000 0.000 0.347 1.332 -4.000 0.000 Covariate matrix - Tx1 group XG3 1.000 0.000 0.000 0.333 0.500 -1.000 0.058 0.000 0.000 0.000 1.000 1.000 1.000 0.333 0.500 -1.000 0.058 0.333 0.500 -1.000 1.000 2.000 4.000 0.333 0.500 -1.000 0.058 0.666 1.000 -2.000 1.000 4.000 16.000 0.333 0.500 -1.000 0.058 1.332 2.000 -4.000 Covariate matrix - Tx2 group XG4 1.000 0.000 0.000 0.333 0.500 1.000 0.154 0.000 0.000 0.000 1.000 1.000 1.000 0.333 0.500 1.000 0.154 0.333 0.500 1.000 1.000 2.000 4.000 0.333 0.500 1.000 0.154 0.666 1.000 2.000 1.000 4.000 16.000 0.333 0.500 1.000 0.154 1.332 2.000 4.000 Observed logits - time by group OLOGIT -1.558 -1.005 -0.677 -0.040 -2.556 -1.457 -1.766 -1.386 -1.483 -1.476 -1.636 -1.153 -1.503 -1.470 -1.214 -1.067 Observed probabilities - time by group OPROB 0.174 0.268 0.337 0.490 0.072 0.189 0.146 0.200 0.185 0.186 0.163 0.240 0.182 0.187 0.229 0.256 Estimated logits - time by group ELOGIT -1.721 -0.987 -0.811 -0.236 -1.982 -1.467 -1.339 -0.887 -1.983 -1.687 -1.606 -1.278 -1.205 -1.347 -1.361 -1.281 Estimated probabilities - time by group EPROB 0.152 0.271 0.308 0.441 0.121 0.187 0.208 0.292 0.121 0.156 0.167 0.218 0.231 0.206 0.204 0.217