In the previous chapter, we estimated the language of new countries starting from their flag. For this purpose, we used KNN algorithm that is a supervised learning algorithm. We built KNN and measured its accuracy cross validating the estimated language. In this chapter, we will see how to measure the accuracy in a more reliable way and we will tune the KNN parameters to improve its performance. To be able to do the tasks in this chapter, it's not necessary for you to have read the previous chapter, although it is recommended so that you can order to understand how the KNN algorithm works.
In this chapter, you will learn how to:
Validate the accuracy of an algorithm
Tune the algorithm parameters
Select the most relevant data features
Optimize the parameters and the features together