ALS Implicit

This page analyzes the hyperparameter tuning results for the implicit-feedback ALS matrix factorization model.

Parameter Search Space

/home/mde48/lenskit/lenskit-codex/.venv/lib/python3.12/site-packages/ray/tune/search/sample.py:700: RayDeprecationWarning: The `base` argument is deprecated. Please remove it as it is not actually needed in this method.
Parameter Type Distribution Values Selected
embedding_size Integer LogUniform 4 ≤ \(x\) ≤ 512 24
regularization.user Float LogUniform 1e-05 ≤ \(x\) ≤ 1 0.0163
regularization.item Float LogUniform 1e-05 ≤ \(x\) ≤ 1 0.0271
damping.user Float LogUniform 1e-12 ≤ \(x\) ≤ 100 78.7
damping.item Float LogUniform 1e-12 ≤ \(x\) ≤ 100 3.3e-06
weight Float Uniform 5 ≤ \(x\) ≤ 100 7.52

Final Result

Searching selected the following configuration:

{
    'embedding_size': 24,
    'regularization': {'user': 0.016258224693422706, 'item': 0.02707865274273186},
    'damping': {'user': 78.68903352299135, 'item': 3.300706088518047e-06},
    'weight': 7.522183838780201,
    'epochs': 6
}

With these metrics:

{
    'RBP': 0.17067951204460352,
    'LogRBP': 2.0262722902150383,
    'NDCG': 0.4214122573243161,
    'RecipRank': 0.32709071985844707,
    'TrainTask': '65840d0c-0829-4399-90fb-9e7422ccd93b',
    'TrainTime': None,
    'TrainCPU': None,
    'max_epochs': 30,
    'done': True,
    'training_iteration': 6,
    'trial_id': '2fde4a2f',
    'date': '2025-05-06_23-24-29',
    'timestamp': 1746588269,
    'time_this_iter_s': 84.51204633712769,
    'time_total_s': 392.13457226753235,
    'pid': 81223,
    'hostname': 'CCI-ws21',
    'node_ip': '10.248.127.152',
    'config': {
        'embedding_size': 24,
        'regularization': {'user': 0.016258224693422706, 'item': 0.02707865274273186},
        'damping': {'user': 78.68903352299135, 'item': 3.300706088518047e-06},
        'weight': 7.522183838780201,
        'epochs': 6
    },
    'time_since_restore': 392.13457226753235,
    'iterations_since_restore': 6
}

Parameter Analysis

Embedding Size

The embedding size is the hyperparameter that most affects the model’s fundamental logic, so let’s look at performance as a fufnction of it:

Learning Parameters

Iteration Completion

How many iterations, on average, did we complete?

How did the metric progress in the best result?

How did the metric progress in the longest results?