In the previous tutorial, we covered how to use the K Nearest Neighbors algorithm via Scikit-Learn to achieve 95% accuracy in predicting benign vs malignant tumors based on tumor attributes. Now, we're going to dig into how K Nearest Neighbors works so we have a full understanding of the algorithm itself, to better understand when it will and wont work for us.
We will come back to our breast cancer dataset, using it on our custom-made K Nearest Neighbors algorithm and compare it to Scikit-Learn's, but we're going to start off with some very simple data first. K Nearest Neighbors boils down to proximity, not by group, but by individual points. Thus, all this algorithm is actually doing is computing distance between points, and then picking the most popular class of the top K classes of points nearest to it. There are various ways to compute distance on a plane, many of which you can use here, but the most accepted version is Euclidean Distance, named after Euclid, a famous mathematician who is popularly referred to as the father of Geometry, and he definitely wrote the book (The Elements) on it.

pythonprogramming.net
twitter.com/sentdex
www.facebook.com/pythonprogramming.net/
plus.google.com/+sentdex

1. Introduction to Machine Learning
2. Regression Intro
3. Regression Features and Labels
4. Regression Training and Testing
5. Regression forecasting and predicting
6. Pickling and Scaling
7. Regression How it Works
8. How to program the Best Fit Slope
9. How to program the Best Fit Line
10. R Squared Theory
11. Programming R Squared
12. Testing Assumptions
13. Classification w/ K Nearest Neighbors Intro
14. K Nearest Neighbors Application
15. Euclidean Distance
16. Creating Our K Nearest Neighbors A
17. Writing our own K Nearest Neighbors in Code
18. Applying our K Nearest Neighbors Algorithm
19. Final thoughts on K Nearest Neighbors
20. Support Vector Machine Intro and Application
21. Understanding Vectors
22. Support Vector Assertion
23. Support Vector Machine Fundamentals
24. Support Vector Machine Optimization
25. Creating an SVM from scratch
26. SVM Training
27. SVM Optimization
28. Completing SVM from Scratch
29. Kernels Introduction
30. Why Kernels
31. Soft Margin SVM
32. Soft Margin SVM and Kernels with CVXOPT
33. SVM Parameters
34. Clustering Introduction
35. Handling Non-Numeric Data
36. K Means with Titanic Dataset
37. Custom K Means
38. K Means from Scratch
39. Mean Shift Intro
40. Mean Shift with Titanic Dataset
41. Mean Shift from Scratch
42. Mean Shift Dynamic Bandwidth

The objective of this course is to give you a holistic understanding of machine learning, covering theory, application, and inner workings of supervised, unsupervised, and deep learning algorithms.

In this series, we'll be covering linear regression, K Nearest Neighbors, Support Vector Machines (SVM), flat clustering, hierarchical clustering, and neural networks.