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root / _FullBNT / BNT / general / log_marg_lik_complete.m @ 8:b5b38998ef3b
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function L = log_marg_lik_complete(bnet, cases, clamped) |
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% LOG_MARG_LIK_COMPLETE Compute sum_m sum_i log P(x(i,m)| x(pi_i,m)) for a completely observed data set |
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% L = log_marg_lik_complete(bnet, cases, clamped) |
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% |
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% This differs from log_lik_complete because we integrate out the parameters. |
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% If there is a missing data, you must use an inference engine. |
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% cases(i,m) is the value assigned to node i in case m. |
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% (If there are vector-valued nodes, cases should be a cell array.) |
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% clamped(i,m) = 1 if node i was set by intervention in case m (default: clamped = zeros) |
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% Clamped nodes contribute a factor of 1.0 to the likelihood. |
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% |
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% If there is a single case, clamped is a list of the clamped nodes, not a bit vector. |
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if iscell(cases), usecell = 1; else usecell = 0; end |
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n = length(bnet.dag); |
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ncases = size(cases, 2); |
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if n ~= size(cases, 1) |
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error('data should be of size nnodes * ncases');
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end |
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if ncases == 1 |
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if nargin < 3, clamped = []; end |
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clamp_set = clamped; |
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clamped = zeros(n,1); |
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clamped(clamp_set) = 1; |
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else |
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if nargin < 3, clamped = zeros(n,ncases); end |
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end |
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L = 0; |
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for i=1:n |
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ps = parents(bnet.dag, i); |
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e = bnet.equiv_class(i); |
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u = find(clamped(i,:)==0); |
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L = L + log_marg_prob_node(bnet.CPD{e}, cases(i,u), cases(ps,u));
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end |
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