public List <SimilarUser <ISvdBoostedKnnUser> > CalculateKNearestNeighbours(ISvdBoostedKnnUser user, IEnumerable <ISvdBoostedKnnUser> users, int nearestNeighboursCount)
{
var neighbours = new List <SimilarUser <ISvdBoostedKnnUser> >();
foreach (var neighbour in users)
{
if (neighbour == user)
{
continue;
}
var s = CalculateSimilarity(user, neighbour);
if (s <= 0.0)
{
continue;
}
neighbours.Add(new SimilarUser <ISvdBoostedKnnUser>(neighbour, s));
neighbours.Sort();
while (neighbours.Count > nearestNeighboursCount)
{
neighbours.RemoveAt(neighbours.Count - 1);
}
}
return(neighbours);
}
public override float CalculateSimilarity(ISvdBoostedKnnUser user, ISvdBoostedKnnUser neighbour)
{
return(base.CalculateSimilarity(user, neighbour) * ContentSimilarityEstimator.GetSimilarity(user, neighbour));
}
public virtual float CalculateSimilarity(ISvdBoostedKnnUser user, ISvdBoostedKnnUser neighbour)
{
var s = SimilarityEstimator.GetSimilarity(user, neighbour);
return(s);
}