lenskit.metrics.RankingMetricBase

class lenskit.metrics.RankingMetricBase(n=None, *, k=None)

Bases: Metric

Base class for most ranking metrics, implementing an n parameter for truncation.

Parameters:

• n (int | None) – Specify the length cutoff for rankings. Rankings longer than this will be truncated prior to measurement.

• k (int | None) – Deprecated alias for n.

Stability:

Caller (see Stability Levels).

__init__(n=None, *, k=None)

Parameters:

• n (int | None)

• k (int | None)

Methods

__init__([n, k])
extract_list_metrics(data, /)	Extract per-list metric(s) from intermediate measurement data.
measure_list(output, test, /)	Compute measurements for a single list.
summarize(values, /)	Aggregate intermediate values into summary statistics.
truncate(items)	Truncate an item list if it is longer than n.

Attributes

k
label	Default name — class name, optionally @N.
n	The maximum length of rankings to consider.
set_k

n: int | None = None

The maximum length of rankings to consider.

property label

Default name — class name, optionally @N.

truncate(items)

Truncate an item list if it is longer than n.

Parameters:

items (ItemList)