Mô tả

Cluster analysis is a staple of unsupervised machine learning and data science.

It is very useful for data mining and big data because it automatically finds patterns in the data, without the need for labels, unlike supervised machine learning.

In a real-world environment, you can imagine that a robot or an artificial intelligence won’t always have access to the optimal answer, or maybe there isn’t an optimal correct answer. You’d want that robot to be able to explore the world on its own, and learn things just by looking for patterns.

Do you ever wonder how we get the data that we use in our supervised machine learning algorithms?

We always seem to have a nice CSV or a table, complete with Xs and corresponding Ys.

If you haven’t been involved in acquiring data yourself, you might not have thought about this, but someone has to make this data!

Those “Y”s have to come from somewhere, and a lot of the time that involves manual labor.

Sometimes, you don’t have access to this kind of information or it is infeasible or costly to acquire.

But you still want to have some idea of the structure of the data. If you're doing data analytics automating pattern recognition in your data would be invaluable.

This is where unsupervised machine learning comes into play.

In this course we are first going to talk about clustering. This is where instead of training on labels, we try to create our own labels! We’ll do this by grouping together data that looks alike.

There are 2 methods of clustering we’ll talk about: k-means clustering and hierarchical clustering.

Next, because in machine learning we like to talk about probability distributions, we’ll go into Gaussian mixture models and kernel density estimation, where we talk about how to "learn" the probability distribution of a set of data.

One interesting fact is that under certain conditions, Gaussian mixture models and k-means clustering are exactly the same! We’ll prove how this is the case.

All the algorithms we’ll talk about in this course are staples in machine learning and data science, so if you want to know how to automatically find patterns in your data with data mining and pattern extraction, without needing someone to put in manual work to label that data, then this course is for you.

All the materials for this course are FREE. You can download and install Python, Numpy, and Scipy with simple commands on Windows, Linux, or Mac.

This course focuses on "how to build and understand", not just "how to use". Anyone can learn to use an API in 15 minutes after reading some documentation. It's not about "remembering facts", it's about "seeing for yourself" via experimentation. It will teach you how to visualize what's happening in the model internally. If you want more than just a superficial look at machine learning models, this course is for you.

"If you can't implement it, you don't understand it"

  • Or as the great physicist Richard Feynman said: "What I cannot create, I do not understand".

  • My courses are the ONLY courses where you will learn how to implement machine learning algorithms from scratch

  • Other courses will teach you how to plug in your data into a library, but do you really need help with 3 lines of code?

  • After doing the same thing with 10 datasets, you realize you didn't learn 10 things. You learned 1 thing, and just repeated the same 3 lines of code 10 times...


Suggested Prerequisites:

  • matrix addition, multiplication

  • probability

  • Python coding: if/else, loops, lists, dicts, sets

  • Numpy coding: matrix and vector operations, loading a CSV file


WHAT ORDER SHOULD I TAKE YOUR COURSES IN?:

  • Check out the lecture "Machine Learning and AI Prerequisite Roadmap" (available in the FAQ of any of my courses, including the free Numpy course)

Bạn sẽ học được gì

Understand the regular K-Means algorithm

Understand and enumerate the disadvantages of K-Means Clustering

Understand the soft or fuzzy K-Means Clustering algorithm

Implement Soft K-Means Clustering in Code

Understand Hierarchical Clustering

Explain algorithmically how Hierarchical Agglomerative Clustering works

Apply Scipy's Hierarchical Clustering library to data

Understand how to read a dendrogram

Understand the different distance metrics used in clustering

Understand the difference between single linkage, complete linkage, Ward linkage, and UPGMA

Understand the Gaussian mixture model and how to use it for density estimation

Write a GMM in Python code

Explain when GMM is equivalent to K-Means Clustering

Explain the expectation-maximization algorithm

Understand how GMM overcomes some disadvantages of K-Means

Understand the Singular Covariance problem and how to fix it

Yêu cầu

  • Know how to code in Python and Numpy
  • Install Numpy and Scipy
  • Matrix arithmetic, probability

Nội dung khoá học

8 sections

Introduction to Unsupervised Learning

6 lectures
Introduction
05:03
Course Outline
04:34
What is unsupervised learning used for?
05:31
Why Use Clustering?
09:20
Where to get the code
04:36
How to Succeed in this Course
03:04

K-Means Clustering

22 lectures
An Easy Introduction to K-Means Clustering
07:06
Hard K-Means: Exercise Prompt 1
09:13
Hard K-Means: Exercise 1 Solution
11:09
Hard K-Means: Exercise Prompt 2
05:04
Hard K-Means: Exercise 2 Solution
07:08
Hard K-Means: Exercise Prompt 3
06:55
Hard K-Means: Exercise 3 Solution
16:22
Hard K-Means Objective: Theory
13:01
Hard K-Means Objective: Code
05:13
Soft K-Means
05:41
The Soft K-Means Objective Function
01:39
Soft K-Means in Python Code
10:03
How to Pace Yourself
03:19
Visualizing Each Step of K-Means
02:18
Examples of where K-Means can fail
07:32
Disadvantages of K-Means Clustering
02:13
How to Evaluate a Clustering (Purity, Davies-Bouldin Index)
06:33
Using K-Means on Real Data: MNIST
05:00
One Way to Choose K
05:15
K-Means Application: Finding Clusters of Related Words
08:38
Clustering for NLP and Computer Vision: Real-World Applications
06:58
Suggestion Box
03:10

Hierarchical Clustering

5 lectures
Visual Walkthrough of Agglomerative Hierarchical Clustering
02:35
Agglomerative Clustering Options
03:38
Using Hierarchical Clustering in Python and Interpreting the Dendrogram
04:38
Application: Evolution
14:00
Application: Donald Trump vs. Hillary Clinton Tweets
18:34

Gaussian Mixture Models (GMMs)

11 lectures
Gaussian Mixture Model (GMM) Algorithm
15:31
Write a Gaussian Mixture Model in Python Code
18:54
Practical Issues with GMM / Singular Covariance
09:07
Comparison between GMM and K-Means
03:55
Kernel Density Estimation
06:24
GMM vs Bayes Classifier (pt 1)
09:28
GMM vs Bayes Classifier (pt 2)
11:30
Expectation-Maximization (pt 1)
11:45
Expectation-Maximization (pt 2)
02:24
Expectation-Maximization (pt 3)
08:09
Future Unsupervised Learning Algorithms You Will Learn
01:01

Setting Up Your Environment (FAQ by Student Request)

3 lectures
Pre-Installation Check
04:12
Anaconda Environment Setup
20:20
How to install Numpy, Scipy, Matplotlib, Pandas, IPython, Theano, and TensorFlow
17:32

Extra Help With Python Coding for Beginners (FAQ by Student Request)

4 lectures
How to Code by Yourself (part 1)
15:54
How to Code by Yourself (part 2)
09:23
Proof that using Jupyter Notebook is the same as not using it
12:29
Python 2 vs Python 3
04:38

Effective Learning Strategies for Machine Learning (FAQ by Student Request)

4 lectures
How to Succeed in this Course (Long Version)
10:24
Is this for Beginners or Experts? Academic or Practical? Fast or slow-paced?
22:04
Machine Learning and AI Prerequisite Roadmap (pt 1)
11:18
Machine Learning and AI Prerequisite Roadmap (pt 2)
16:07

Appendix / FAQ Finale

2 lectures
What is the Appendix?
02:48
BONUS
05:48

Đánh giá của học viên

Chưa có đánh giá
Course Rating
5
0%
4
0%
3
0%
2
0%
1
0%

Bình luận khách hàng

Viết Bình Luận

Bạn đánh giá khoá học này thế nào?

image

Đăng ký get khoá học Udemy - Unica - Gitiho giá chỉ 50k!

Get khoá học giá rẻ ngay trước khi bị fix.