Abstract:Missing data often exists in real-world datasets, requiring significant time and effort for imputation to learn accurate machine learning (ML) models. In this paper, we demonstrate that imputing all missing values is not always necessary to achieve an accurate ML model. We introduce the concept of minimal data imputation, which ensures accurate ML models trained over the imputed dataset. Implementing minimal imputation guarantees both minimal imputation effort and optimal ML models. We propose algorithms to find exact and approximate minimal imputation for various ML models. Our extensive experiments indicate that our proposed algorithms significantly reduce the time and effort required for data imputation.
Abstract:Real-world data is often incomplete and contains missing values. To train accurate models over real-world datasets, users need to spend a substantial amount of time and resources imputing and finding proper values for missing data items. In this paper, we demonstrate that it is possible to learn accurate models directly from data with missing values for certain training data and target models. We propose a unified approach for checking the necessity of data imputation to learn accurate models across various widely-used machine learning paradigms. We build efficient algorithms with theoretical guarantees to check this necessity and return accurate models in cases where imputation is unnecessary. Our extensive experiments indicate that our proposed algorithms significantly reduce the amount of time and effort needed for data imputation without imposing considerable computational overhead.