lenskit.splitting.SampleFrac

class lenskit.splitting.SampleFrac(frac, rng=None)

Bases: HoldoutMethod

Randomly select a fraction of test rows per user/item.

Stability:

Caller (see Stability Levels).

Parameters:

• frac (float) – The fraction items to select for testing.

• rng (lenskit.random.RNGInput) – The random number generator or seed (see Random Seeds).

fraction: float

rng: numpy.random.Generator

__call__(items)

Subset an item list (in the uncommon case of item-based holdouts, the item list actually holds user IDs).

Parameters:

• udf – The item list from which holdout items should be selected.

• items (lenskit.data.ItemList)

Returns:

The list of test items.

Return type:

lenskit.data.ItemList