Machine Learning

Cold Start Problem

The challenge of making recommendations for new users (who have no history) or new items (which have no ratings). Cold start is a fundamental difficulty in recommendation systems.

Why It Matters

Cold start affects every recommendation system's launch phase and every new user's first experience. Solutions determine whether users stick around or leave.

Example

A new user signing up for Spotify with no listening history — the system has no data to personalize recommendations, so it must use other signals like demographics.

Think of it like...

Like being a new student at a school — nobody knows you yet, so the cafeteria cannot recommend meals based on your preferences until you have been there a while.

Related Terms