code: private void getLogOddsRatios(VarTensor[] inMsgs, double[][] spanWeights) {
          Algebra s = inMsgs[0].getAlgebra();
          
          // Compute the odds ratios of the messages for each edge in the tree.
          DoubleArrays.fill(spanWeights, Double.NEGATIVE_INFINITY);
          for (VarTensor inMsg : inMsgs) {
              SpanVar span = (SpanVar) inMsg.getVars().get(0);
              double oddsRatio = s.toLogProb(inMsg.getValue(SpanVar.TRUE)) - s.toLogProb(inMsg.getValue(SpanVar.FALSE));
              spanWeights[span.getStart()][span.getEnd()] = oddsRatio;                
          }
  
          checkSpanWeights(spanWeights);
      }
docs: Computes the log odds ratio for each edge. w_{ij} = \mu_{ij}(1) / \mu_{ij}(0)