wolffd@0: function L = log_nextcase_prob_node(CPD, self_ev, pev, test_self_ev, test_pev) wolffd@0: % LOG_NEXTCASE_PROB_NODE compute the joint distribution of a node (tabular) of a new case given wolffd@0: % completely observed data. wolffd@0: % wolffd@0: % The input arguments are mainly similar with log_marg_prob_node(CPD, self_ev, pev, usecell), wolffd@0: % but add test_self_ev, test_pev, and without usecell wolffd@0: % test_self_ev(m) is the evidence on this node in a test case. wolffd@0: % test_pev(i) is the evidence on the i'th parent in the test case (if there are any parents). wolffd@0: % wolffd@0: % Written by qian.diao@intel.com wolffd@0: wolffd@0: ncases = length(self_ev); wolffd@0: sz = CPD.sizes; wolffd@0: nparents = length(sz)-1; wolffd@0: assert(ncases == size(pev, 2)); wolffd@0: wolffd@0: if nargin < 6 wolffd@0: %usecell = 0; wolffd@0: if iscell(self_ev) wolffd@0: usecell = 1; wolffd@0: else wolffd@0: usecell = 0; wolffd@0: end wolffd@0: end wolffd@0: wolffd@0: wolffd@0: if ncases==0 wolffd@0: L = 0; wolffd@0: return; wolffd@0: elseif ncases==1 % speedup the sequential learning case; here need correction!!! wolffd@0: CPT = CPD.CPT; wolffd@0: % We assume the CPTs are already set to the mean of the posterior (due to bayes_update_params) wolffd@0: if usecell wolffd@0: x = cat(1, pev{:})'; wolffd@0: y = self_ev{1}; wolffd@0: else wolffd@0: %x = pev(:)'; wolffd@0: x = pev; wolffd@0: y = self_ev; wolffd@0: end wolffd@0: switch nparents wolffd@0: case 0, p = CPT(y); wolffd@0: case 1, p = CPT(x(1), y); wolffd@0: case 2, p = CPT(x(1), x(2), y); wolffd@0: case 3, p = CPT(x(1), x(2), x(3), y); wolffd@0: otherwise, wolffd@0: ind = subv2ind(sz, [x y]); wolffd@0: p = CPT(ind); wolffd@0: end wolffd@0: L = log(p); wolffd@0: else wolffd@0: % We ignore the CPTs here and assume the prior has not been changed wolffd@0: wolffd@0: % We arrange the data as in the following example. wolffd@0: % Let there be 2 parents and 3 cases. Let p(i,m) be parent i in case m, wolffd@0: % and y(m) be the child in case m. Then we create the data matrix wolffd@0: % wolffd@0: % p(1,1) p(1,2) p(1,3) wolffd@0: % p(2,1) p(2,2) p(2,3) wolffd@0: % y(1) y(2) y(3) wolffd@0: if usecell wolffd@0: data = [cell2num(pev); cell2num(self_ev)]; wolffd@0: else wolffd@0: data = [pev; self_ev]; wolffd@0: end wolffd@0: counts = compute_counts(data, sz); wolffd@0: wolffd@0: % compute the (N_ijk'+ N_ijk)/(N_ij' + N_ij) under the condition of 1_m+1,ijk = 1 wolffd@0: L = predict_family(counts, CPD.prior, test_self_ev, test_pev); wolffd@0: end wolffd@0: wolffd@0: