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1 function CPD = update_ess(CPD, fmarginal, evidence, ns, cnodes, hidden_bitv)
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2 % UPDATE_ESS Update the Expected Sufficient Statistics of a hhmmF node.
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3 % function CPD = update_ess(CPD, fmarginal, evidence, ns, cnodes, hidden_bitv)
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4
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5 % Figure out the node numbers associated with each parent
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6 % so we extract evidence from the right place
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7 dom = fmarginal.domain; % Q(1) .. Q(d) F(d+1) F(d)
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8 Qps = fmarginal.domain(1:end-2);
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9 Q = Qps(end);
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10 Qps = Qps(1:end-1);
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11
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12 Qsz = CPD.Qsizes(CPD.Q);
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13 Qpsz = prod(CPD.Qsizes(CPD.Qps)); % may be 1
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14
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15 % We assume the F node are always hidden, but allow some of the Q nodes
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16 % to be observed. We do case analysis for speed.
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17 %We only extract prob from fmarginal.T when F(d+1)=2 i.e., model below has finished.
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18 % wrong -> % We sum over the possibilities that F(d+1) = 1 or 2
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19
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20 obs_self = ~hidden_bitv(Q);
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21 if obs_self
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22 self_val = evidence{Q};
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23 end
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24
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25 if isempty(Qps) % independent of parent context
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26 counts = zeros(Qsz, 2);
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27 %fmarginal.T(Q(d), F(d+1), F(d))
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28 if obs_self
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29 marg = myreshape(fmarginal.T, [1 2 2]);
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30 counts(self_val,:) = marg(1,2,:);
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31 %counts(self_val,:) = marg(1,1,:) + marg(1,2,:);
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32 else
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33 marg = myreshape(fmarginal.T, [Qsz 2 2]);
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34 counts = squeeze(marg(:,2,:));
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35 %counts = squeeze(marg(:,2,:)) + squeeze(marg(:,1,:));
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36 end
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37 else
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38 counts = zeros(Qpsz, Qsz, 2);
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39 %fmarginal.T(Q(1:d-1), Q(d), F(d+1), F(d))
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40 obs_Qps = ~any(hidden_bitv(Qps)); % we assume that all or none of the Q parents are observed
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41 if obs_Qps
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42 Qps_val = subv2ind(Qpsz, cat(1, evidence{Qps}));
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43 end
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44 if obs_self & obs_Qps
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45 marg = myreshape(fmarginal.T, [1 1 2 2]);
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46 counts(Qps_val, self_val, :) = squeeze(marg(1,1,2,:));
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47 %counts(Qps_val, self_val, :) = squeeze(marg(1,1,2,:)) + squeeze(marg(1,1,1,:));
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48 elseif ~obs_self & obs_Qps
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49 marg = myreshape(fmarginal.T, [1 Qsz 2 2]);
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50 counts(Qps_val, :, :) = squeeze(marg(1,:,2,:));
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51 %counts(Qps_val, :, :) = squeeze(marg(1,:,2,:)) + squeeze(marg(1,:,1,:));
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52 elseif obs_self & ~obs_Qps
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53 error('not yet implemented')
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54 else
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55 marg = myreshape(fmarginal.T, [Qpsz Qsz 2 2]);
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56 counts(:, :, :) = squeeze(marg(:,:,2,:));
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57 %counts(:, :, :) = squeeze(marg(:,:,2,:)) + squeeze(marg(:,:,1,:));
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58 end
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59 end
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60
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61 CPD.sub_CPD_term = update_ess_simple(CPD.sub_CPD_term, counts);
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