PrecisionAndRecall Class Reference

Precision and recall at different positions in the list More...

Static Public Member Functions
static double	AP (IList< int > ranked_items, ICollection< int > correct_items)
	Compute the average precision (AP) of a list of ranked items More...
static int	HitsAt (IList< int > ranked_items, ICollection< int > correct_items, int n)
	Compute the number of hits until position N of a list of ranked items More...
static Dictionary< int, double >	PrecisionAt (IList< int > ranked_items, ICollection< int > correct_items, IList< int > ns)
	Compute the precision at N of a list of ranked items at several N More...
static double	PrecisionAt (IList< int > ranked_items, ICollection< int > correct_items, int n)
	Compute the precision at N of a list of ranked items More...
static Dictionary< int, double >	RecallAt (IList< int > ranked_items, ICollection< int > correct_items, IList< int > ns)
	Compute the recall at N of a list of ranked items at several N More...
static double	RecallAt (IList< int > ranked_items, ICollection< int > correct_items, int n)
	Compute the recall at N of a list of ranked items More...

Detailed Description

Precision and recall at different positions in the list

Precision and recall are classical evaluation measures from information retrieval.

This class contains methods for computing precision and recall up to different positions in the recommendation list, and the average precision (AP).

The mean of the AP over different users is called mean average precision (MAP)

Member Function Documentation

static double AP ( IList< int >  ranked_items, ICollection< int >  correct_items  )

inlinestatic

Compute the average precision (AP) of a list of ranked items

See p. 147 of Introduction to Information Retrieval by Manning, Raghavan, Schütze.

Parameters

ranked_items	a list of ranked item IDs, the highest-ranking item first
correct_items	a collection of positive/correct item IDs

Returns

the AP for the given list

static int HitsAt ( IList< int >  ranked_items, ICollection< int >  correct_items, int  n  )

inlinestatic

Compute the number of hits until position N of a list of ranked items

Parameters

ranked_items	a list of ranked item IDs, the highest-ranking item first
correct_items	a collection of positive/correct item IDs
n	the cutoff position in the list

Returns

the hits at N for the given data

static Dictionary<int, double> PrecisionAt ( IList< int >  ranked_items, ICollection< int >  correct_items, IList< int >  ns  )

inlinestatic

Compute the precision at N of a list of ranked items at several N

Parameters

ranked_items	a list of ranked item IDs, the highest-ranking item first
correct_items	a collection of positive/correct item IDs
ns	the cutoff positions in the list

Returns

the precision at N for the given data at the different positions N

static double PrecisionAt ( IList< int >  ranked_items, ICollection< int >  correct_items, int  n  )

inlinestatic

Compute the precision at N of a list of ranked items

Parameters

ranked_items	a list of ranked item IDs, the highest-ranking item first
correct_items	a collection of positive/correct item IDs
n	the cutoff position in the list

Returns

the precision at N for the given data

static Dictionary<int, double> RecallAt ( IList< int >  ranked_items, ICollection< int >  correct_items, IList< int >  ns  )

inlinestatic

Compute the recall at N of a list of ranked items at several N

Parameters

ranked_items	a list of ranked item IDs, the highest-ranking item first
correct_items	a collection of positive/correct item IDs
ns	the cutoff positions in the list

Returns

the recall at N for the given data at the different positions N

static double RecallAt ( IList< int >  ranked_items, ICollection< int >  correct_items, int  n  )

inlinestatic

Compute the recall at N of a list of ranked items

Parameters

ranked_items	a list of ranked item IDs, the highest-ranking item first
correct_items	a collection of positive/correct item IDs
n	the cutoff position in the list

Returns

the recall at N for the given data

---

The documentation for this class was generated from the following file:

• PrecisionAndRecall.cs