Exploratory data analysis

The second step of a data science project is to carry out Exploratory Data Analysis (EDA). By doing so, we get to know the data we are supposed to work with. This is also the step during which we test the extent of our domain knowledge. For example, the company we are working for might assume that the majority of its customers are people between the age of 18 and 2But is this actually the case? While doing EDA we might also run into some patterns that we do not understand, which are then a starting point for a discussion with our stakeholders.

While doing EDA, we can try to answer the questions:

• What kind of data do we actually have, and how should we treat different data types?
• What is the distribution of the variables?
• Are there outliers in the data, and how can we treat them?
• Are any transformations required? For example, some models work better with (or require) normally distributed variables, so we might want to use techniques such as log transformation...