Temel Kavramlar
Selection bias in the preference elicitation stage can negatively impact the performance of subsequent item recommendations, but existing debiasing methods can help mitigate this effect.
Özet
This paper explores the problem of selection bias in the preference elicitation (PE) stage of recommendation systems. The authors note that while selection bias in user interactions (e.g., ratings) has been widely studied, the effects of bias in the PE stage have not been investigated.
The authors first discuss how common debiasing methods for item recommendation, such as inverse propensity scoring (IPS), can be applied to the PE stage. They then introduce a method for simulating a PE stage from static recommendation datasets, as there is currently no publicly available dataset that represents PE interactions.
Through experiments on both a semi-synthetic dataset (based on the Yahoo! R3 dataset) and a fully-synthetic dataset, the authors demonstrate that:
- Ignoring the effect of selection bias in the PE stage can lead to an exacerbation of overrepresentation in subsequent item recommendations.
- Applying debiasing methods, such as IPS, can significantly improve the performance of item recommendations by alleviating the effects of selection bias in the PE stage.
The authors propose their simulation method and initial results as a starting point and motivation for future research into this important but overlooked problem setting.
İstatistikler
The rating distribution over item topics in the Coat dataset shows a clear popularity bias, with a small number of topics receiving most of the ratings.
The genre popularity distribution in the MovieLens dataset also exhibits a skewed distribution, indicating the presence of selection bias.
Alıntılar
"Selection bias in user interaction data is widely studied [12, 13, 13, 18, 19, 22], to the best of our knowledge, previous work has not considered the effects of selection bias in PE."
"Our experimental results in the simulator reveal that selection bias in the PE stage does, indeed, have negative effects on subsequent item recommendation."
"We find that existing debiasing methods can be adapted to reduce these effects, leading to significantly better recommendations."