Fundamentals of Statistics contains material of various lectures and courses of H. Lohninger on statistics, data analysis and here for more.

Exploratory Data Analysis

Exploratory data analysis (EDA) can be seen in contrast to traditional hypothesis testing. While the testing of hypotheses always requires an a priori assumption (or hypothesis) about the data (e.g. "There is a difference in the life expectation between smokers and non-smokers"), exploratory data analysis is not based on any a priori assumptions. Any method can be used to identify systematic relations between the variables.

In a typical exploratory data analysis all variables are taken into account using both graphical (e.g. scatter plots) and formal methods (e.g. principal component analysis) to search for systematic patterns.