COMP 135 Introduction to Machine Learning First day of class - - PowerPoint PPT Presentation

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COMP 135 Introduction to Machine Learning First day of class - - PowerPoint PPT Presentation

COMP 135 Introduction to Machine Learning First day of class Spring 2019 https://www.cs.tufts.edu/comp/135/2019s/ Many slides attributable to: Emily Fox (UW), Finale Doshi-Velez (Harvard), Erik Sudderth (UCI), & Liping Liu (Tufts) 1


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COMP 135 Introduction to Machine Learning

First day of class Spring 2019

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https://www.cs.tufts.edu/comp/135/2019s/

Many slides attributable to: Emily Fox (UW), Finale Doshi-Velez (Harvard), Erik Sudderth (UCI), & Liping Liu (Tufts)

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Mike Hughes - Tufts COMP 135 - Spring 2019

Why Machine Learning?

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Mike Hughes - Tufts COMP 135 - Spring 2019

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Image Credit: Emily Fox

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Mike Hughes - Tufts COMP 135 - Spring 2019

Artificial Intelligence (AI)

  • Study of “intelligent systems”, with many parts:

logic, planning, search, probabilistic reasoning, learning from experience, interacting with other agents, etc.

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Machine Learning (ML)

  • Study of algorithms that learn from

experience/data to perform a task

  • Task output: a prediction or a decision

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Mike Hughes - Tufts COMP 135 - Spring 2019

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The Machine Learning Process

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Mike Hughes - Tufts COMP 135 - Spring 2019

Past data (or “experience”) Performance measure Task / Goal input data (now) prediction / decision (now)

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Why take this course?

Mike Hughes - Tufts COMP 135 - Spring 2019

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Why take this course?

Our goal is to prepare students to effectively apply machine learning methods to problems that might arise in "the real world" -- in industry, medicine, education, and beyond. Gain skills and understanding for a future as:

  • Developer using ML “out-of-the-box”
  • ML methods researcher

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Mike Hughes - Tufts COMP 135 - Spring 2019

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Why take this course?

Students will be able to:

  • Think systematically
  • Compare/contrast each method’s strengths & limitations
  • Deploy rapidly
  • Hands-on experience with open-source libraries
  • Evaluate carefully
  • Design experiments with task-appropriate performance

metrics and strong baselines

  • Report uncertainty in performance

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Mike Hughes - Tufts COMP 135 - Spring 2019

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What skills will we learn?

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Mike Hughes - Tufts COMP 135 - Spring 2019

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What will we learn?

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Mike Hughes - Tufts COMP 135 - Spring 2019

Supervised Learning Unsupervised Learning Reinforcement Learning

Data, Label Pairs Performance measure Task data x label y

{xn, yn}N

n=1

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Mike Hughes - Tufts COMP 135 - Spring 2019

Task: Regression

Supervised Learning Unsupervised Learning Reinforcement Learning

regression

x y y

is a continuous variable e.g. sales in $$

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Mike Hughes - Tufts COMP 135 - Spring 2019

Regression Example: Uber

Supervised Learning Unsupervised Learning Reinforcement Learning

regression

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Regression Example: Uber

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Mike Hughes - Tufts COMP 135 - Spring 2019

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Regression Example: Uber

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Mike Hughes - Tufts COMP 135 - Spring 2019

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Mike Hughes - Tufts COMP 135 - Spring 2019

Task: Classification

Supervised Learning Unsupervised Learning Reinforcement Learning

classification

y

x2 x1

is a discrete variable (red or blue)

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Classification Example: Swype

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Mike Hughes - Tufts COMP 135 - Spring 2019

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What will we learn?

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Mike Hughes - Tufts COMP 135 - Spring 2019

Supervised Learning Unsupervised Learning Reinforcement Learning

Data, Label Pairs Performance measure Task data x label y

{xn, yn}N

n=1

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Mike Hughes - Tufts COMP 135 - Spring 2019

What will we learn?

Data Examples data x

Supervised Learning Unsupervised Learning Reinforcement Learning

{xn}N

n=1

Task summary

  • f x

Performance measure

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Task: Clustering

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Mike Hughes - Tufts COMP 135 - Spring 2019

Supervised Learning Unsupervised Learning Reinforcement Learning

clustering

x2 x1

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Clustering Example: News

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Mike Hughes - Tufts COMP 135 - Spring 2019

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Task: Embedding

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Mike Hughes - Tufts COMP 135 - Spring 2019

Supervised Learning Unsupervised Learning Reinforcement Learning

embedding

x2 x1

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Example: Genes vs. geography

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Mike Hughes - Tufts COMP 135 - Spring 2019

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Mike Hughes - Tufts COMP 135 - Spring 2019

Task: Recommendation

Supervised Learning Unsupervised Learning Reinforcement Learning

recommendation

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Recommendation Example

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Histories of states, actions, rewards Task Next action a Performance measure

What will we learn?

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Mike Hughes - Tufts COMP 135 - Spring 2019

Supervised Learning Unsupervised Learning Reinforcement Learning

{st, at, rt, st+1, . . .}N

n=1

Recent history

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RL example: Pancake robot

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Mike Hughes - Tufts COMP 135 - Spring 2019

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Mike Hughes - Tufts COMP 135 - Spring 2019

What will we learn this semester?

Supervised Learning Unsupervised Learning Reinforcement Learning

~ 1 week 0.5 homeworks ~ 2 weeks 1.5 homeworks ~ 10 weeks 6 homeworks 3 projects

Take COMP 136 Take COMP 150 – RL (Prof. Jivko Sinapov) Take COMP 136 Take COMP 150 – Deep Learning If I want more?

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What we won’t cover

  • Active learning
  • Transfer learning
  • Semi-supervised learning
  • Learning theory
  • ….. lots more

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Mike Hughes - Tufts COMP 135 - Spring 2019

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Who is teaching?

  • Instructor: Prof. Mike Hughes
  • TA Staff
  • Mike Pietras
  • Rui Chen
  • Minh Nguyen
  • Duc Nguyen
  • Wayne Tang

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Mike Hughes - Tufts COMP 135 - Spring 2019

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Problem: When will ICU patient need intervention?

Interventions:

  • mechanical ventilation
  • blood pressure drugs

Early prediction helps: prepare patient plan staffing try less aggressive options early

Ghassemi, Wu, Hughes, et al. AMIA CRI 2017

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Cohort from MIMIC-III dataset

36,050 patients

  • from Beth-Israel Deaconess in Boston 2001-2012
  • kept all adults with record within 6-360 hours

mimic.physionet.org

(Johnson et al. Sci. Data 2016)

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Observed data

7 nurse-validated vital signs (hourly) heart rate, blood pressure, temp., SpO2, … 11 lab measurements (much less than hourly) hematocrit, lactate, …

each channel standardized to mean=0, var=1 with carry-and-hold for missing data

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Mike Hughes - Tufts COMP 135 - Spring 2019

Task: predict need in advance

+2 hrs ahead

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Mike Hughes - Tufts COMP 135 - Spring 2019

Vasopressor prediction : 1 hr ahead

Area-under-ROC

static demographics (age, race, etc) dynamic patient vitals at time t “embedding” using time-series model

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Key Stakeholder Questions

  • How should we fill in missing values?
  • How to deal with imbalance data?
  • most patients never get drug X
  • How to deal with imbalanced mistake costs?
  • remove ventilator too early ends life, too late costs $$
  • How uncertain are predictions?
  • How will this generalize to a new hospital?

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Mike Hughes - Tufts COMP 135 - Spring 2019

We can start to answer many of these in COMP 135

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Logistics

  • Course website (take a tour)
  • https://www.cs.tufts.edu/comp/135/2019s/
  • Discussions on Piazza
  • Lectures every Mon & Wed
  • Recitation Sessions with TAs every Mon
  • Deliverables: 2 exams, 8 homeworks, 3 projects
  • Collaboration Policy

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Mike Hughes - Tufts COMP 135 - Spring 2019

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Let’s Get Started!

  • Setup your Python environment ASAP
  • First recitation is Mon 1/21
  • Get help with your Python env.
  • Learn basics of arrays, plotting, etc
  • HW0 due NEXT WEEK (Wed 1/23 at 11:59pm)

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Mike Hughes - Tufts COMP 135 - Spring 2019