We have stepped into an era where we arebuildingsmart or intelligent machines. This smartness or intelligence is infused into the machine with the help of smart algorithms based on mathematics/statistics. These algorithms enable the system or machine to learn automatically without any human intervention. As an example of this, today we are surrounded by a number of mobile applications. One of the prime messaging apps of today in WhatsApp (currently owned by Facebook). Whenever we type a message into a textbox of WhatsApp, and we type, for example, I am..., we get a few word prompts popping up, such as ..going home, Rahul, traveling tonight, and so on. Can we guess what's happening here and why? Multiple questions come up:
- What is it that the system is learning?
- Where does it learn from?
- How does it learn?
Let's answer all these questions in this chapter.
In this chapter, we will cover the following topics:
- Statistical models
- Learning curves
- Curve fitting
- Modeling cultures
- Overfitting and regularization
- Train, validation, and test
- Cross-validation and model selection
- Bootstrap method