The document analyzes different weighting schemes in collaborative filtering to address the problem of popularity bias. It describes how standard collaborative filtering approaches can over-recommend popular items. The paper presents experiments testing two similarity weighting strategies (linear inverse and inverse user frequency) in different scenarios using two movie rating datasets. The results show that popularity weighting improves precision for users with a moderate number of ratings when the rating scale is compact, but not when the number of ratings is very low or very high.