One of the main concerns is the nature of the missing values. Let’s consider extremes for simplicity. If missing at random we have not to care about. But if missing shows structures that covariate with substantive variables we have to…

Data mining is at the core of the knowledge discovery process. However, an initial preprocessing step is crucial for assuring reliable results within this process. Preprocessing of data is a time-consuming and non-trivial task since data quality issues should be…