Estimating missing data using novel correlation maximization based methods

The accurate estimation of missing data plays a vital role in ensuring a high level of data quality. The missing values should be imputed before performing data mining, machine learning, and other data processing tasks. Ten correlation-based imputation methods are proposed in this paper. All of these methods try to maximize the correlation between a missing feature and other features. The maximization is achieved by selecting segments of data that have strong correlations. The proposed approach involves the following main steps to impute each missing instance. First, a base set is selected from complete instances. Second, data segments with strong correlations are generated using the base set and the rest of the complete instances. Finally, each missing value is imputed by applying linear models to the discovered segments of data. This study considers seven real datasets from different fields with different missing rates. The imputation quality of the proposed methods is compared to those of seven other imputation approaches in terms of three well-known evaluation criteria. The experimental results reveal that the proposed approach has better imputation performance than competing imputation techniques in most cases. (C) 2020 Elsevier B.V. All rights reserved.