public double userSimilarity(long userID1, long userID2)
{
DataModel model = base.getDataModel();
FastIDSet other = model.getItemIDsFromUser(userID1);
FastIDSet set2 = model.getItemIDsFromUser(userID2);
int num = other.size();
int num2 = set2.size();
if ((num == 0) && (num2 == 0))
{
return(double.NaN);
}
if ((num == 0) || (num2 == 0))
{
return(0.0);
}
int num3 = (num < num2) ? set2.intersectionSize(other) : other.intersectionSize(set2);
if (num3 == 0)
{
return(double.NaN);
}
int num4 = (num + num2) - num3;
return(((double)num3) / ((double)num4));
}
protected override void prepareTraining()
{
int num;
int num2;
base.prepareTraining();
RandomWrapper wrapper = RandomUtils.getRandom();
this.p = new double[base.dataModel.getNumUsers()][];
for (num = 0; num < this.p.Length; num++)
{
this.p[num] = new double[base.numFeatures];
num2 = 0;
while (num2 < RatingSGDFactorizer.FEATURE_OFFSET)
{
this.p[num][num2] = 0.0;
num2++;
}
num2 = RatingSGDFactorizer.FEATURE_OFFSET;
while (num2 < base.numFeatures)
{
this.p[num][num2] = wrapper.nextGaussian() * base.randomNoise;
num2++;
}
}
this.y = new double[base.dataModel.getNumItems()][];
for (num = 0; num < this.y.Length; num++)
{
this.y[num] = new double[base.numFeatures];
num2 = 0;
while (num2 < RatingSGDFactorizer.FEATURE_OFFSET)
{
this.y[num][num2] = 0.0;
num2++;
}
for (num2 = RatingSGDFactorizer.FEATURE_OFFSET; num2 < base.numFeatures; num2++)
{
this.y[num][num2] = wrapper.nextGaussian() * base.randomNoise;
}
}
this.itemsByUser = new Dictionary <int, List <int> >();
IEnumerator <long> enumerator = base.dataModel.getUserIDs();
while (enumerator.MoveNext())
{
long current = enumerator.Current;
int num4 = base.userIndex(current);
FastIDSet set = base.dataModel.getItemIDsFromUser(current);
List <int> list = new List <int>(set.size());
this.itemsByUser[num4] = list;
foreach (long num5 in set)
{
int item = base.itemIndex(num5);
list.Add(item);
}
}
}
public double userSimilarity(long userID1, long userID2)
{
DataModel model = base.getDataModel();
FastIDSet other = model.getItemIDsFromUser(userID1);
FastIDSet set2 = model.getItemIDsFromUser(userID2);
int num = other.size();
int num2 = set2.size();
int intersection = (num < num2) ? set2.intersectionSize(other) : other.intersectionSize(set2);
return(doSimilarity(num, num2, intersection));
}
private void findClusters(List <FastIDSet> newClusters)
{
if (clusteringByThreshold)
{
KeyValuePair <FastIDSet, FastIDSet> nearestPair = findNearestClusters(newClusters);
FastIDSet _cluster1 = nearestPair.Key;
FastIDSet _cluster2 = nearestPair.Value;
if (_cluster1 != null && _cluster2 != null)
{
FastIDSet cluster1 = _cluster1;
FastIDSet cluster2 = _cluster2;
while (clusterSimilarity.getSimilarity(cluster1, cluster2) >= clusteringThreshold)
{
newClusters.Remove(cluster1);
newClusters.Remove(cluster2);
FastIDSet merged = new FastIDSet(cluster1.size() + cluster2.size());
merged.addAll(cluster1);
merged.addAll(cluster2);
newClusters.Add(merged);
nearestPair = findNearestClusters(newClusters);
var __cluster1 = nearestPair.Key;
var __cluster2 = nearestPair.Value;
if (__cluster1 == null || __cluster2 == null)
{
break;
}
cluster1 = __cluster1;
cluster2 = __cluster2;
}
}
}
else
{
while (newClusters.Count > numClusters)
{
KeyValuePair <FastIDSet, FastIDSet> nearestPair = findNearestClusters(newClusters);
FastIDSet _cluster1 = nearestPair.Key;
FastIDSet _cluster2 = nearestPair.Value;
if (_cluster1 == null || _cluster2 == null)
{
break;
}
FastIDSet cluster1 = _cluster1;
FastIDSet cluster2 = _cluster2;
newClusters.Remove(cluster1);
newClusters.Remove(cluster2);
FastIDSet merged = new FastIDSet(cluster1.size() + cluster2.size());
merged.addAll(cluster1);
merged.addAll(cluster2);
newClusters.Add(merged);
}
}
}
private void addSomeOf(FastIDSet possibleItemIDs, FastIDSet itemIDs)
{
if (itemIDs.size() > this.maxItemsPerUser)
{
SamplingLongPrimitiveIterator iterator = new SamplingLongPrimitiveIterator(itemIDs.GetEnumerator(), ((double)this.maxItemsPerUser) / ((double)itemIDs.size()));
while (iterator.MoveNext())
{
possibleItemIDs.add(iterator.Current);
}
}
else
{
possibleItemIDs.addAll(itemIDs);
}
}
public FastIDSet getRelevantItemsIDs(long userID, int at, double relevanceThreshold, DataModel dataModel)
{
PreferenceArray array = dataModel.getPreferencesFromUser(userID);
FastIDSet set = new FastIDSet(at);
array.sortByValueReversed();
for (int i = 0; (i < array.length()) && (set.size() < at); i++)
{
if (array.getValue(i) >= relevanceThreshold)
{
set.add(array.getItemID(i));
}
}
return(set);
}
public override int getNumUsersWithPreferenceFor(long itemID1, long itemID2)
{
FastIDSet other = this.preferenceForItems.get(itemID1);
if (other == null)
{
return(0);
}
FastIDSet set2 = this.preferenceForItems.get(itemID2);
if (set2 == null)
{
return(0);
}
return((other.size() < set2.size()) ? set2.intersectionSize(other) : other.intersectionSize(set2));
}
public double userSimilarity(long userID1, long userID2)
{
DataModel model = base.getDataModel();
FastIDSet other = model.getItemIDsFromUser(userID1);
FastIDSet set2 = model.getItemIDsFromUser(userID2);
long num = other.size();
long num2 = set2.size();
long num3 = (num < num2) ? ((long)set2.intersectionSize(other)) : ((long)other.intersectionSize(set2));
if (num3 == 0L)
{
return(double.NaN);
}
long num4 = model.getNumItems();
double num5 = LogLikelihood.logLikelihoodRatio(num3, num2 - num3, num - num3, ((num4 - num) - num2) + num3);
return(1.0 - (1.0 / (1.0 + num5)));
}
private List <RecommendedItem> computeTopRecsForCluster(FastIDSet cluster)
{
DataModel dataModel = getDataModel();
FastIDSet possibleItemIDs = new FastIDSet();
var it = cluster.GetEnumerator();
while (it.MoveNext())
{
possibleItemIDs.addAll(dataModel.getItemIDsFromUser(it.Current));
}
TopItems.Estimator <long> estimator = new Estimator(this, cluster);
List <RecommendedItem> topItems =
TopItems.getTopItems(possibleItemIDs.size(), possibleItemIDs.GetEnumerator(), null, estimator);
log.debug("Recommendations are: {}", topItems);
return(topItems);
}
public override PreferenceArray getPreferencesFromUser(long userID)
{
FastIDSet set = this.preferenceFromUsers.get(userID);
if (set == null)
{
throw new NoSuchUserException(userID);
}
PreferenceArray array = new BooleanUserPreferenceArray(set.size());
int i = 0;
IEnumerator <long> enumerator = set.GetEnumerator();
while (enumerator.MoveNext())
{
array.setUserID(i, userID);
array.setItemID(i, enumerator.Current);
i++;
}
return(array);
}
private bool mergeClosestClusters(int numUsers, List <FastIDSet> clusters, bool done)
{
// We find a certain number of closest clusters...
List <ClusterClusterPair> queue = findClosestClusters(numUsers, clusters);
// List<ClusterClusterPair> queue = new List<ClusterClusterPair>();
//foreach (var item in _queue)
//{
// queue.Enqueue(item);
//}
// The first one is definitely the closest pair in existence so we can cluster
// the two together, put it back into the set of clusters, and start again. Instead
// we assume everything else in our list of closest cluster pairs is still pretty good,
// and we cluster them too.
for (int n = 0; n < queue.Count; n++)
{
//}
//while (queue.Count > 0)
//{
if (!clusteringByThreshold && clusters.Count <= numClusters)
{
done = true;
break;
}
ClusterClusterPair top = queue[n];
queue.RemoveAt(n);
if (clusteringByThreshold && top.getSimilarity() < clusteringThreshold)
{
done = true;
break;
}
FastIDSet cluster1 = top.getCluster1();
FastIDSet cluster2 = top.getCluster2();
// Pull out current two clusters from clusters
var clusterIterator = clusters;
bool removed1 = false;
bool removed2 = false;
for (int m = 0; m < clusterIterator.Count; m++)
{
if (!(removed1 && removed2))
{
FastIDSet current = clusterIterator[m];
// Yes, use == here
if (!removed1 && cluster1 == current)
{
clusterIterator.RemoveAt(m);
m--;
removed1 = true;
}
else if (!removed2 && cluster2 == current)
{
clusterIterator.RemoveAt(m);
m--;
removed2 = true;
}
}
// The only catch is if a cluster showed it twice in the list of best cluster pairs;
// have to remove the others. Pull out anything referencing these clusters from queue
for (int k = 0; k < queue.Count; k++)
{
//}
// for (Iterator<ClusterClusterPair> queueIterator = queue.iterator(); queueIterator.hasNext(); )
// {
ClusterClusterPair pair = queue[k];
FastIDSet pair1 = pair.getCluster1();
FastIDSet pair2 = pair.getCluster2();
if (pair1 == cluster1 || pair1 == cluster2 || pair2 == cluster1 || pair2 == cluster2)
{
queue.RemoveAt(k);
//queueIterator.remove();
}
}
// Make new merged cluster
FastIDSet merged = new FastIDSet(cluster1.size() + cluster2.size());
merged.addAll(cluster1);
merged.addAll(cluster2);
// Compare against other clusters; update queue if needed
// That new pair we're just adding might be pretty close to something else, so
// catch that case here and put it back into our queue
for (var i = 0; i < clusters.Count; i++)
{
FastIDSet cluster = clusters[i];
double similarity = clusterSimilarity.getSimilarity(merged, cluster);
if (similarity > queue[queue.Count - 1].getSimilarity())
{
var queueIterator = queue.GetEnumerator();
while (queueIterator.MoveNext())
{
if (similarity > queueIterator.Current.getSimilarity())
{
n--;
// queueIterator.previous();
break;
}
}
queue.Add(new ClusterClusterPair(merged, cluster, similarity));
}
}
// Finally add new cluster to list
clusters.Add(merged);
}
}
return(done);
}
public IRStatistics evaluate(RecommenderBuilder recommenderBuilder, DataModelBuilder dataModelBuilder, DataModel dataModel, IDRescorer rescorer, int at, double relevanceThreshold, double evaluationPercentage)
{
int num = dataModel.getNumItems();
RunningAverage average = new FullRunningAverage();
RunningAverage average2 = new FullRunningAverage();
RunningAverage average3 = new FullRunningAverage();
RunningAverage average4 = new FullRunningAverage();
int num2 = 0;
int num3 = 0;
IEnumerator <long> enumerator = dataModel.getUserIDs();
while (enumerator.MoveNext())
{
long current = enumerator.Current;
if (this.random.nextDouble() < evaluationPercentage)
{
Stopwatch stopwatch = new Stopwatch();
stopwatch.Start();
PreferenceArray prefs = dataModel.getPreferencesFromUser(current);
double num5 = double.IsNaN(relevanceThreshold) ? computeThreshold(prefs) : relevanceThreshold;
FastIDSet relevantItemIDs = this.dataSplitter.getRelevantItemsIDs(current, at, num5, dataModel);
int num6 = relevantItemIDs.size();
if (num6 > 0)
{
FastByIDMap <PreferenceArray> trainingUsers = new FastByIDMap <PreferenceArray>(dataModel.getNumUsers());
IEnumerator <long> enumerator2 = dataModel.getUserIDs();
while (enumerator2.MoveNext())
{
this.dataSplitter.processOtherUser(current, relevantItemIDs, trainingUsers, enumerator2.Current, dataModel);
}
DataModel model = (dataModelBuilder == null) ? new GenericDataModel(trainingUsers) : dataModelBuilder.buildDataModel(trainingUsers);
try
{
model.getPreferencesFromUser(current);
}
catch (NoSuchUserException)
{
continue;
}
int num7 = num6 + model.getItemIDsFromUser(current).size();
if (num7 >= (2 * at))
{
Recommender recommender = recommenderBuilder.buildRecommender(model);
int num8 = 0;
List <RecommendedItem> list = recommender.recommend(current, at, rescorer);
foreach (RecommendedItem item in list)
{
if (relevantItemIDs.contains(item.getItemID()))
{
num8++;
}
}
int count = list.Count;
if (count > 0)
{
average.addDatum(((double)num8) / ((double)count));
}
average2.addDatum(((double)num8) / ((double)num6));
if (num6 < num7)
{
average3.addDatum(((double)(count - num8)) / ((double)(num - num6)));
}
double num10 = 0.0;
double num11 = 0.0;
for (int i = 0; i < count; i++)
{
RecommendedItem item2 = list[i];
double num13 = 1.0 / log2(i + 2.0);
if (relevantItemIDs.contains(item2.getItemID()))
{
num10 += num13;
}
if (i < num6)
{
num11 += num13;
}
}
if (num11 > 0.0)
{
average4.addDatum(num10 / num11);
}
num2++;
if (count > 0)
{
num3++;
}
stopwatch.Stop();
log.info("Evaluated with user {} in {}ms", new object[] { current, stopwatch.ElapsedMilliseconds });
log.info("Precision/recall/fall-out/nDCG/reach: {} / {} / {} / {} / {}", new object[] { average.getAverage(), average2.getAverage(), average3.getAverage(), average4.getAverage(), ((double)num3) / ((double)num2) });
}
}
}
}
return(new IRStatisticsImpl(average.getAverage(), average2.getAverage(), average3.getAverage(), average4.getAverage(), ((double)num3) / ((double)num2)));
}
public override int getNumUsersWithPreferenceFor(long itemID)
{
FastIDSet set = this.preferenceForItems.get(itemID);
return((set == null) ? 0 : set.size());
}
