The fourth step or the modeling step is where the actual analysis and ML takes place. This step utilizes the clean and formatted data prepared in the previous step for modeling purposes. This is an iterative process and works in sync with the data preparation step as models/algorithms require data in different settings/formats with varying set of attributes.

This step involves selecting relevant tools and frameworks along with the selection of a modeling technique or algorithms. This step includes model building, evaluation, and fine-tuning of models, based on the expectations and criteria laid down during the business understanding phase.