static public ConditionalGaussianDistribution GetInstance()
{
ConditionalGaussianDistribution aLinearGaussian = new ConditionalGaussianDistribution();
return(aLinearGaussian);
}
public ConditionalGaussianDistribution CreateDistributionGaussianOrNull(Branch branch, OptimizationParameterList gaussianParameters)
{
if (branch.Length == 0)
{
Debug.WriteLine("Branch length of zero observed");
}
ConditionalGaussianDistribution plainConditionalDistribution = GetPlainConditionalGaussianDistribution(branch, gaussianParameters);
return(plainConditionalDistribution);
}
protected override ConditionalGaussianDistribution GetPlainConditionalGaussianDistribution(BranchOrLeaf branchOrLeaf, OptimizationParameterList gaussianParameters)
{
double alphaTimesVariance = gaussianParameters["AlphaVariance"].Value;
ConditionalGaussianDistribution plainConditionalDistribution = ConditionalGaussianDistribution.GetInstance();
// 0 (const part of mean) ax + b, Mean := b
plainConditionalDistribution.Mean = 0;
// 1 (ax + b = x), linearCoefficent := a.
plainConditionalDistribution.LinearCoefficent = 1;
plainConditionalDistribution.Variance = alphaTimesVariance * branchOrLeaf.Length;
return(plainConditionalDistribution);
}
protected override ConditionalGaussianDistribution GetPlainConditionalGaussianDistribution(BranchOrLeaf branchOrLeaf, OptimizationParameterList gaussianParameters)
{
double alphaTimesVariance = gaussianParameters["AlphaVariance"].Value;
double mean = gaussianParameters["Mean"].Value;
double alpha = gaussianParameters["Alpha"].Value;
ConditionalGaussianDistribution plainConditionalDistribution = ConditionalGaussianDistribution.GetInstance();
double root1MinusAlphaTimesBranchLength = Math.Sqrt(1 - alpha * branchOrLeaf.Length);
// ax + b, Mean := b
plainConditionalDistribution.Mean = mean * (1.0 - root1MinusAlphaTimesBranchLength);
// ax + b = x, LinearCoefficent := a
plainConditionalDistribution.LinearCoefficent = root1MinusAlphaTimesBranchLength;
plainConditionalDistribution.Variance = alphaTimesVariance * branchOrLeaf.Length;
return(plainConditionalDistribution);
}
public ConditionalGaussianDistribution CreateDistributionGaussianOrNull(
Leaf leaf,
OptimizationParameterList gaussianParameters,
Converter <Leaf, SufficientStatistics> predictorLeafToBoolStats)
{
if (leaf.Length == 0)
{
Debug.WriteLine("Branch length of zero observed");
}
ConditionalGaussianDistribution plainConditionalDistribution = GetPlainConditionalGaussianDistribution(leaf, gaussianParameters);
BooleanStatistics hasPredictor = (BooleanStatistics)predictorLeafToBoolStats(leaf);
if (hasPredictor.IsMissing())
{
return(null); // Predictor data is missing, so skip this leaf.
}
double delta = GetOffset(gaussianParameters);
return(LabelledLeafDistributionGaussian.CreateDistributionGaussianOrNull(plainConditionalDistribution, hasPredictor, delta));
}