protected override void GetGradientInOneQuery(int query, int threadIndex)
{
int begin = Dataset.Boundaries[query];
int end = Dataset.Boundaries[query + 1];
short[] labels = Dataset.Ratings;
float[] sizes = SizeAdjustedLogLossUtil.GetSizeLabels(Dataset);
Contracts.Check(Dataset.NumDocs == sizes.Length, "Mismatch between dataset and labels");
if (end - begin <= 1)
{
return;
}
Array.Clear(_gradient, begin, end - begin);
for (int d1 = begin; d1 < end - 1; ++d1)
{
for (int d2 = d1 + 1; d2 < end; ++d2)
{
float size = sizes[d1];
//Compute Lij
float sizeAdjustedLoss = 0.0F;
for (int d3 = d2; d3 < end; ++d3)
{
size -= sizes[d3];
if (size >= 0.0F && labels[d3] > 0)
{
sizeAdjustedLoss = 1.0F;
}
else if (size < 0.0F && labels[d3] > 0)
{
sizeAdjustedLoss = (1.0F + (size / sizes[d3]));
}
if (size <= 0.0F || sizeAdjustedLoss > 0.0F)
{
// Exit condition- we have reached size or size adjusted loss is already populated.
break;
}
}
double scoreDiff = _scores[d1] - _scores[d2];
float labelDiff = ((float)labels[d1] - sizeAdjustedLoss);
double delta = 0.0;
if (_algo == SizeAdjustedLogLossCommandLineArgs.CostFunctionMode.SizeAdjustedPageOrdering)
{
delta = (_llc * labelDiff) / (1.0 + Math.Exp(_llc * labelDiff * scoreDiff));
}
else
{
delta = (double)labels[d1] - ((double)(labels[d1] + sizeAdjustedLoss) / (1.0 + Math.Exp(-scoreDiff)));
}
_gradient[d1] += delta;
_gradient[d2] -= delta;
if (_mode == SizeAdjustedLogLossCommandLineArgs.LogLossMode.Pairwise)
{
break;
}
}
}
}
protected override Test ConstructTestForTrainingData()
{
return(new SizeAdjustedLogLossTest(ConstructScoreTracker(TrainSet), cmd.scoreRangeFileName, SizeAdjustedLogLossUtil.GetSizeLabels(TrainSet), cmd.loglosscoef));
}
protected override void InitializeTests()
{
Tests.Add(new SizeAdjustedLogLossTest(ConstructScoreTracker(TrainSet), cmd.scoreRangeFileName, SizeAdjustedLogLossUtil.GetSizeLabels(TrainSet), cmd.loglosscoef));
if (ValidSet != null)
{
Tests.Add(new SizeAdjustedLogLossTest(ConstructScoreTracker(ValidSet), cmd.scoreRangeFileName, SizeAdjustedLogLossUtil.GetSizeLabels(ValidSet), cmd.loglosscoef));
}
if (TestSets != null && TestSets.Length > 0)
{
for (int t = 0; t < TestSets.Length; ++t)
{
Tests.Add(new SizeAdjustedLogLossTest(ConstructScoreTracker(TestSets[t]), cmd.scoreRangeFileName, SizeAdjustedLogLossUtil.GetSizeLabels(TestSets[t]), cmd.loglosscoef));
}
}
}
protected override void PrepareLabels(IChannel ch)
{
trainSetSizeLabels = SizeAdjustedLogLossUtil.GetSizeLabels(TrainSet);
}
