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Introduction to Data Science
Lecture 12
Machine Learning
CIS 5930/4930 – Fall 2021
Assignments
CIS 5930/4930 – Fall 2021
• Homework 1
• Posted on Canvas 9/10
• Due 9/17 at 3pm on Canvas
What is Machine Learning
Learning is any process by which a system improves
performance from experience.”
– Herbert Simon
Definition by Tom Mitchell (1998):
Machine Learning is the study of algorithms that
• Improve their performance P
• at some task T
• with experience E.
• A well-defined learning task is given by
CIS 5930/4930 – Fall 2021
What can a Learning Algorithm Do
• Recognizing patterns
• Facial identities or facial expressions
• Handwritten or spoken words
• Medical images
• Generating patterns
• Generating images or motion sequences
• Recognizing anomalies
• Unusual credit card transactions
• Unusual patterns of sensor readings in a nuclear
power plant
• Prediction
• Future stock prices or currency exchange rates
CIS 5930/4930 – Fall 2021
Some Application Areas
• Web search
• Computational biology
• Finance
• E-commerce
• Space exploration
• Robotics
• Information extraction
• Social networks
• Debugging software
CIS 5930/4930 – Fall 2021
Oversimplified Machine Learning
CIS 5930/4930 – Fall 2021
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In More Detail
CIS 5930/4930 – Fall 2021
Age Gender Chest Pain
Blood
Pressure Cholesterol
Blood
Sugar Result
64 0 3 140.00 313.00 0.00 no
43 1 4 110.00 211.00 0.00 no
45 1 4 142.00 309.00 0.00 yes
58 1 4 128.00 259.00 0.00 yes
50 1 4 144.00 200.00 0.00 yes
51 0 2 140 210.00 0.00 ???
• Training Data
• 6 features (age, gender, …) + label (yes/no)
• Goal
• Predict the label on new data
Training Data, Features
CIS 5930/4930 – Fall 2021
Weather Prediction
• Training Data
• Features
• We have no data
• Where can we get it
• How much do we need
• Goal
• Predict if it will be sunny or cloudy weather
CIS 5930/4930 – Fall 2021
Regression
CIS 5930/4930 – Fall 2021
Regression
CIS 5930/4930 – Fall 2021
Linear Regression
CIS 5930/4930 – Fall 2021
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Linear Regression
CIS 5930/4930 – Fall 2021
Linear Regression
CIS 5930/4930 – Fall 2021
Linear Regression
CIS 5930/4930 – Fall 2021
Linear Regression
CIS 5930/4930 – Fall 2021
Linear Regression
CIS 5930/4930 – Fall 2021
Linear Regression
CIS 5930/4930 – Fall 2021
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Linear Regression
CIS 5930/4930 – Fall 2021
Linear Regression
CIS 5930/4930 – Fall 2021
Linear Regression
CIS 5930/4930 – Fall 2021
Linear Regression
CIS 5930/4930 – Fall 2021
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