NicolasHug / Surprise

A Python scikit for building and analyzing recommender systems
http://surpriselib.com
BSD 3-Clause "New" or "Revised" License
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"Was_impossible" meaning #413

Open mfahadakbar opened 2 years ago

mfahadakbar commented 2 years ago

Description

What does "was_impossible = False" mean in the output of the predict method? I tried to find it out through documentation, but couldn't find any explanation. Thank you

NicolasHug commented 2 years ago

This happens when the algorithm isn't able to output a prediction, for example when the user or the item isn't part of the training set. You'll find more details of its usage throughout the code: https://github.com/NicolasHug/Surprise/search?q=PredictionImpossible

When was_impossible = True, the prediction is set to the global mean rating of the training set.