An instance of QSPRDataset can also be initialized directly (without a DataSource) by the user through a tabular format (e.g. CSV/TSV) or an SDF file. The user always needs to specify one or more properties to be predicted during initialization or during the lifetime of the data set. These are specified as TargetProperty, which are associated with a specific modelling TargetTask, such as REGRESSION or MULTICLASS.