Let's go out on the street and ask people about social networks.

Well, I use Facebook and Twitter.

There's other edges that if we take them out, things are still connected.

What is homophily?

Dance has never had a better friend than technology.

Barack Obama won (Applause) because he mobilized people as never before through the use of social networks.

Laughs

It's very exciting work.

Yes.

Unit 5 combines ideas from graph search that we studied in Unit 3 with ideas about computing statistic that we look at in Unit 4 and it puts these tools together to give us the way of finding shortest path in these networks.

For a more efficient way, take CS215! See ya there. Excuse me!

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So there's a fair amount of interconnection between a node's neighbors.

That's all I'd like to say about shortest paths and weighted graphs in this unit.

So, lets imagine there is some problem called graph partitioning which is a real problem.

This example illustrates two things that are central to this course.

This has been fairly well studied.

The first is the idea of a social network.

Unit four explores the notion of statistics, numbers that summarize complex structures like social networks.

What it's telling us is that capitalism is going to become more social.

That our ideas reach other people who think as we do.

A community of people with the same interests.

What happens if Facebook, Google, Twitter, Linkedln, cell phones, GPS, Foursquare, Yelp, Travel Advisor, all these things you deal with every day turn out to be electronic tattoos?

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What attracted me the most was Facebook.

By the end of this year, there'll be nearly a billion people on this planet that actively use social networking sites.

Michael So that's not a connection we can make.

I did not go and measured these animals' brains.

Hi! I'm Michael Lipman. I'm going to be teaching CS215 for Udacity.

There's these issues that are taking place.

We weren't able to get video footage of our conversation together but I think you'll find it interesting anyway.

He has interned at a number of different companies, and this summer he interned with a company called Meebo that does some social networking.

We're going to be looking at Big Theta in the context of understanding the relationship of individuals in a social network and the connections between them.

It's just, how do we make that recurrent and scale it?

So, the nice thing about these structures is they do kind of have an essence of looking like real social network graphs.

But I didn't appear in that comic book with him, so that's not a very good metric.

Is it the political movement that suggests that people should be allowed to marry people of the same sex?

We spend an evening on the social network instead of going to the pub with friends.

That strips all the physical mass out of information, so now it's almost zero cost to copy and share information.

Mexico's problem which, I feel, can be resolved using the social network is disinformation and tha manipulation of information.

Duncan Watts is one of the world experts in analyzing social networks and learning about what's going on inside of that.

No it doesn't change the time, big O or the clustering coefficient in the social network.

No it doesn't change the time, big O or the clustering coefficient in the social network.

Or for example in more common day we say Birds of a feather flock together.

And it creates this kind of social network around a collection of digital photographs that you've actually taken.