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Hello everyone, and welcome to the class on probabilistic graphical models.
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My name is Daphne Koller and I’m a professor at Stanford University.
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We here at Stanford are really excited
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to be able to offer this graduate level Stanford class
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to anyone, anywhere around the world for free.
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So what are probabilistic graphical models?
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Well, it’s a bit complicated to explain
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and we’re going to talk about that in an upcoming video
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but also throughout the entire class.
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In this video, I’d like to tell you a little bit about the format of this class.
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The course is going to be offered over ten weeks worth of material
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plus a final examination at the end.
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The content is going to be conveyed via a set of videos,
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augmented with quizzes to reinforce understanding.
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In addition, there is going to be a weekly problem set
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where the problem sets altogether are going to be worth 25% of the score
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for a total of the nine problem sets for the nine weeks worth of content.
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The problem sets are designed to allow for multiple submissions,
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so that each version of the problem set is going to be a little bit different
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so that you can resubmit the same problem set [a] couple of times
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to make sure that you really mastered the material.
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In addition, there’s going to be a weekly programming assignment,
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and those programming assignments were selected
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to reinforce specific concepts that we’re studying in the course,
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but at the same time to reveal the range of applications
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to which the framework of probabilistic graphical models can be successfully applied.
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So we’re going to have, for example,
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a problem set on how you use probabilistic graphical models
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to understand the inheritance of genetically inherited diseases.
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We’re going to have one that shows
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how you can look at a set of handwritten characters
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and read what’s written there.
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And we’re going to have one that allows you
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to look at a stream of output from a Kinect sensor
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that gives you both video and range data
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and recognize human activities.
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These nine programming assignments are each going to be worth 7% of the score
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for a total of 63%,
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which gives us 12% left for the final exam.
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What background do you need for this class?
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Well, it’s going to be really hard to do this class,
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without some understanding of basic probability theory.
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This doesn’t have to be very advanced stuff.
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We’re talking about things like independence and Bayes' rule
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And just basics of discrete distributions.
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And we also have a few introductory modules
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to refresh your memory about these basic concepts.
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The programming assignments will require
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that you’ve had some experience programming before
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because this is not a programming class.
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We don’t teach you how to program.
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And because this class merges ideas from both probability theory and computer science,
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it’s really important you have some background in algorithms and data structures.
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Recommended, but not strictly necessary—
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and we certainly don’t require it,
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and we give you the background as we go—
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is a little bit of experience, perhaps, in machine learning,
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maybe some simple optimization like gradient descent,
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nothing very sophisticated.
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And it would be helpful to have some experience programming in Matlab or Octave,
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although, here also, we have some introductory modules
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that help you learn this programming language if you haven’t played around with it before.
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A few other issues that are worth noting:
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This class has an honor code.
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This is the norm also for our local Stanford students when they’re taking a Stanford class.
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The honor code here says that you’re allowed to discuss the material,
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in fact even encouraged to discuss the material with your fellow classmates.
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You can even ask clarifying questions about the problems sets and the programming assignments.
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But what you turn in has to be your own work.
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Furthermore, we request that you do not post either the programming assignments
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or their solutions anywhere on the web,
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so that future generations of students can do
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the problems sets and the programming assignments independently as well.
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A second issue to keep in mind is that of time management.
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This is a graduate-level Stanford class
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and it’s considered a difficult one even at Stanford.
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A typical Stanford student can easily spend
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ten to fifteen hours a week on this class,
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and so we would suggest that you budget
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at least that amount of time for your own efforts on this class
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if you don’t want to find yourself running out of time
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when a submission deadline comes around.
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We’ve built in a little slack into the submission deadline,
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so if you don’t manage to submit by the original deadline,
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you have a week’s worth of grace period.
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But then that obviously starts to impinge on the next week’s problem set.
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So we advise that you don’t just keep
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a backlog of assignments throughout the course,
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because it will all end up coming back to bite you in the end.
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Finally, part of the experience of this class
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is interacting with your fellow students,
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so for that purpose we have the discussion forum
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which has proven in other classes
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to be an invaluable resource for interacting with other students,
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asking questions and obtaining a deeper understanding of the material.
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We’re also encouraging you to form study groups—
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these can be physical study groups with people in the same geographical region,
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or online study groups where you can just discuss the material with each other.
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We believe that doing this
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will give you a much better understanding of the material
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and will make the course considerably more fun as well.
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So, to summarize,
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through all these different pieces of the content and the exercises,
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we think that you’ll learn fundamental methods
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in this area of probabilistic graphical models.
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You’ll also get to see and play around with
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a range of real-world applications for which these methods have been applied
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and hopefully you will leave this class with an understanding
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of how to take these ideas and use them in your own work
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in problems that you care about.
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We look forward to seeing you in this class.