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Diffstat (limited to 'sourcecodes/bnt-master/BNT/examples/static/nodeorderExample.m')
| -rw-r--r-- | sourcecodes/bnt-master/BNT/examples/static/nodeorderExample.m | 68 |
1 files changed, 68 insertions, 0 deletions
diff --git a/sourcecodes/bnt-master/BNT/examples/static/nodeorderExample.m b/sourcecodes/bnt-master/BNT/examples/static/nodeorderExample.m new file mode 100644 index 00000000..165f3210 --- /dev/null +++ b/sourcecodes/bnt-master/BNT/examples/static/nodeorderExample.m @@ -0,0 +1,68 @@ +% example to illustrate why nodes must be numbered topologically. +% Due to Shinya OHTANI <ohtani@pdp.crl.sony.co.jp> +% 9 June 2004 + +%%%%%%%%% WRONG RESULTS because 2 -> 1 +% should have P(parent|no evidence) = prior = [03. 0.7] + +node = struct('ChildNode', 1, ... + 'ParentNode', 2); + +adjacency = zeros(2); +adjacency([node.ParentNode], node.ChildNode) = 1; + +value = {{'TRUE'; 'FALSE'}, ... + {'TRUE'; 'FALSE'}}; + +bnet = mk_bnet(adjacency, [2 2]); +bnet.CPD{node.ChildNode} = tabular_CPD(bnet, node.ChildNode, [0.2 0.4 0.8 0.6]); +bnet.CPD{node.ParentNode} = tabular_CPD(bnet, node.ParentNode, [0.3 0.7]); + +evidence = cell(1,2); +% evidence{node.ChildNode} = 1; +% evidence{node.ParentNode} = 1; + +engine = jtree_inf_engine(bnet); +[engine, loglik] = enter_evidence(engine, evidence); + + +marg = marginal_nodes(engine, node.ChildNode); +disp(sprintf(' ChildNode : %8.6f %8.6f',marg.T(1),marg.T(2)) ); +marg = marginal_nodes(engine, node.ParentNode); +disp(sprintf(' ParentNode : %8.6f %8.6f',marg.T(1),marg.T(2)) ); + +% +% ChildNode : 0.534483 0.465517 +% ParentNode : 0.155172 0.844828 +% loglik = 0.15 + + + +%%%%%%%%% RIGHT RESULTS because 1 -> 2 + +node = struct('ChildNode', 2, ... + 'ParentNode', 1); + + +adjacency = zeros(2); +adjacency([node.ParentNode], node.ChildNode) = 1; + +value = {{'TRUE'; 'FALSE'}, ... + {'TRUE'; 'FALSE'}}; + +bnet = mk_bnet(adjacency, [2 2]); +bnet.CPD{node.ChildNode} = tabular_CPD(bnet, node.ChildNode, [0.2 0.4 0.8 0.6]); +bnet.CPD{node.ParentNode} = tabular_CPD(bnet, node.ParentNode, [0.3 0.7]); + +evidence = cell(1,2); +% evidence{node.ChildNode} = 1; +% evidence{node.ParentNode} = 1; + +engine = jtree_inf_engine(bnet); +[engine, loglik] = enter_evidence(engine, evidence); + + +marg = marginal_nodes(engine, node.ChildNode); +disp(sprintf(' ChildNode : %8.6f %8.6f',marg.T(1),marg.T(2)) ); +marg = marginal_nodes(engine, node.ParentNode); +disp(sprintf(' ParentNode : %8.6f %8.6f',marg.T(1),marg.T(2)) ); |
