recpack.metrics.HitK

class recpack.metrics.HitK(K)

Computes the number of hits in a list of Top-K recommendations.

A hit is counted when a recommended item in the top K for this user was interacted with.

Detailed results show which of the items in the list of Top-K recommended items were hits and which were not.

Parameters

K (int) – Size of the recommendation list consisting of the Top-K item predictions.

Methods

calculate(y_true, y_pred)

Computes metric given true labels y_true and predicted scores y_pred.

Attributes

col_names

The names of the columns in the results DataFrame.

name

Name of the metric.

num_items

Dimension of the item-space in both y_true and y_pred

num_users

Dimension of the user-space in both y_true and y_pred after elimination of users without interactions in y_true.

results

Get the detailed results for this metric.

value

Global metric value obtained by summing up scores for every user then taking the average over all users.

calculate(y_true: scipy.sparse._csr.csr_matrix, y_pred: scipy.sparse._csr.csr_matrix) None

Computes metric given true labels y_true and predicted scores y_pred. Only Top-K recommendations are considered.

Detailed metric results can be retrieved with results. Global aggregate metric value is retrieved as value.

Parameters
  • y_true (csr_matrix) – True user-item interactions.

  • y_pred (csr_matrix) – Predicted affinity of users for items.

property col_names

The names of the columns in the results DataFrame.

property name

Name of the metric.

property num_items: int

Dimension of the item-space in both y_true and y_pred

property num_users: int

Dimension of the user-space in both y_true and y_pred after elimination of users without interactions in y_true.

property results: pandas.core.frame.DataFrame

Get the detailed results for this metric.

Contains an entry for every user-item pair in the Top-K recommendations list of every user.

If there is a user with no recommendations, the results DataFrame will contain K rows for that user with item_id = NaN and score = 0.

Returns

The results DataFrame with columns: user_id, item_id, score

Return type

pd.DataFrame

property value

Global metric value obtained by summing up scores for every user then taking the average over all users.