Chapter 2 Probability theory

Before moving to the discussion of statistics, we need to understand the basics of probability theory. In this chapter we will discuss the definition of probability, the definition of random variable then addition and multiplication of probabilities, conditional and independent probabilities and finally the Bayes’ Theorem. All these theoretical ideas form the basis of more advanced statistical tools, which is why they are important.

The software behind this book. The methods described here are implemented in the greybox package for R and Python, which are free and open source.

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