Best practices in the data preparation stage
No machine learning system can be built without data. Therefore, data collection should be our first focus.
Best practice 1 – Completely understanding the project goal
Before starting to collect data, we should make sure that the goal of the project and the business problem is completely understood, as this will guide us on what data sources to look into, and where sufficient domain knowledge and expertise is also required. For example, in a previous chapter, Chapter 7, Predicting Stock Prices with Regression Algorithms, our goal was to predict the future prices of the DJIA index, so we first collected data of its past performance, instead of the past performance of an irrelevant European stock. In Chapter 4, Predicting Online Ad Click-Through with Tree-Based Algorithms, for example, the business problem was to optimize advertising targeting efficiency measured by click-through rate, so we collected...