public void testCorrelation()
{
IDataModel dataModel = getDataModel(
new long[] { 1, 2, 3, 4, 5 },
new Double?[][] {
new double?[] { 1.0, 1.0 },
new double?[] { 1.0, null, 1.0 },
new double?[] { null, null, 1.0, 1.0, 1.0 },
new double?[] { 1.0, 1.0, 1.0, 1.0, 1.0 },
new double?[] { null, 1.0, 1.0, 1.0, 1.0 },
});
LogLikelihoodSimilarity similarity = new LogLikelihoodSimilarity(dataModel);
assertCorrelationEquals(0.12160727029227925, similarity.ItemSimilarity(1, 0));
assertCorrelationEquals(0.12160727029227925, similarity.ItemSimilarity(0, 1));
assertCorrelationEquals(0.5423213660693732, similarity.ItemSimilarity(1, 2));
assertCorrelationEquals(0.5423213660693732, similarity.ItemSimilarity(2, 1));
assertCorrelationEquals(0.6905400104897509, similarity.ItemSimilarity(2, 3));
assertCorrelationEquals(0.6905400104897509, similarity.ItemSimilarity(3, 2));
assertCorrelationEquals(0.8706358464330881, similarity.ItemSimilarity(3, 4));
assertCorrelationEquals(0.8706358464330881, similarity.ItemSimilarity(4, 3));
}
public void testCorrelation()
{
IDataModel dataModel = getDataModel(
new long[] {1, 2, 3, 4, 5},
new Double?[][] {
new double?[]{1.0, 1.0},
new double?[]{1.0, null, 1.0},
new double?[]{null, null, 1.0, 1.0, 1.0},
new double?[]{1.0, 1.0, 1.0, 1.0, 1.0},
new double?[]{null, 1.0, 1.0, 1.0, 1.0},
});
LogLikelihoodSimilarity similarity = new LogLikelihoodSimilarity(dataModel);
assertCorrelationEquals(0.12160727029227925, similarity.ItemSimilarity(1, 0));
assertCorrelationEquals(0.12160727029227925, similarity.ItemSimilarity(0, 1));
assertCorrelationEquals(0.5423213660693732, similarity.ItemSimilarity(1, 2));
assertCorrelationEquals(0.5423213660693732, similarity.ItemSimilarity(2, 1));
assertCorrelationEquals(0.6905400104897509, similarity.ItemSimilarity(2, 3));
assertCorrelationEquals(0.6905400104897509, similarity.ItemSimilarity(3, 2));
assertCorrelationEquals(0.8706358464330881, similarity.ItemSimilarity(3, 4));
assertCorrelationEquals(0.8706358464330881, similarity.ItemSimilarity(4, 3));
}
public void testNoSimilarity()
{
IDataModel dataModel = getDataModel(
new long[] { 1, 2, 3, 4 },
new Double?[][] {
new double?[] { 1.0, null, 1.0, 1.0 },
new double?[] { 1.0, null, 1.0, 1.0 },
new double?[] { null, 1.0, 1.0, 1.0 },
new double?[] { null, 1.0, 1.0, 1.0 },
});
LogLikelihoodSimilarity similarity = new LogLikelihoodSimilarity(dataModel);
assertCorrelationEquals(Double.NaN, similarity.ItemSimilarity(1, 0));
assertCorrelationEquals(Double.NaN, similarity.ItemSimilarity(0, 1));
assertCorrelationEquals(0.0, similarity.ItemSimilarity(2, 3));
assertCorrelationEquals(0.0, similarity.ItemSimilarity(3, 2));
}
public void testNoSimilarity()
{
IDataModel dataModel = getDataModel(
new long[] {1, 2, 3, 4},
new Double?[][] {
new double?[]{1.0, null, 1.0, 1.0},
new double?[]{1.0, null, 1.0, 1.0},
new double?[]{null, 1.0, 1.0, 1.0},
new double?[]{null, 1.0, 1.0, 1.0},
});
LogLikelihoodSimilarity similarity = new LogLikelihoodSimilarity(dataModel);
assertCorrelationEquals(Double.NaN, similarity.ItemSimilarity(1, 0));
assertCorrelationEquals(Double.NaN, similarity.ItemSimilarity(0, 1));
assertCorrelationEquals(0.0, similarity.ItemSimilarity(2, 3));
assertCorrelationEquals(0.0, similarity.ItemSimilarity(3, 2));
}