Great Social Networks in History

The Medici were one of the great ruling families of Europe during the Renaissance.  How did they come to rule?  Not power, or money, or armies, but through the strength of their social network.  And speaking of great historical social networks, analysis of the network of letter-writing during the Enlightenment is helping humanities scholars track the dispersion of great ideas across the world during that time, from Voltaire to Benjamin Franklin and everyone in between.

Relevant links:
https://www2.bc.edu/~jonescq/mb851/Mar12/PadgettAnsell_AJS_1993.pdf
http://republicofletters.stanford.edu/index.html

Medicis
Linear Digressions

How Much to Pay a Spy

A few small encores on auction theory, and then--how can you value a piece of information before you know what it is?  Decision theory has some pointers.  Some highly relevant information if you are trying to figure out how much to pay a spy.

Relevant links:
https://tuecontheoryofnetworks.wordpress.com/2013/02/25/the-origin-of-the-dutch-auction/
http://www.nowozin.net/sebastian/blog/the-fair-price-to-pay-a-spy-an-introduction-to-the-value-of-information.html

How Much to Pay a Spy
Linear Digressions

Sold! Auctions Part 2

The Google ads auction is a special kind of auction, one you might not know as well as the famous English auction (which we talked about in the last episode).  But if it's what Google uses to sell billions of dollars of ad space in real time, you know it must be pretty cool.

Relevant links:
https://en.wikipedia.org/wiki/English_auction
http://people.ischool.berkeley.edu/~hal/Papers/2006/position.pdf
http://www.benedelman.org/publications/gsp-060801.pdf

Auctions Part 2
Linear Digressions

Going Once, Going Twice: Auctions Part 1

The Google AdWords algorithm is (famously) an auction system for allocating a massive amount of online ad space in real time--with that fascinating use case in mind, this episode is part one in a two-part series all about auctions.  We dive into the theory of auctions, and what makes a "good" auction.   

Relevant links:
https://en.wikipedia.org/wiki/English_auction
http://people.ischool.berkeley.edu/~hal/Papers/2006/position.pdf
http://www.benedelman.org/publications/gsp-060801.pdf

Auctions Part 1
Linear Digressions

Unlabeled Supervised Learning--whaaa?

In order to do supervised learning, you need a labeled training dataset.  Or do you...?

Relevant links:
http://www.cs.columbia.edu/~dplewis/candidacy/goldman00enhancing.pdf

Unlabeled Supervised Learning
Linear Digressions

Zipf's Law

Zipf's law is related to the statistics of how word usage is distributed.  As it turns out, this is also strikingly reminiscent of how income is distributed, and populations of cities, and bug reports in software, as well as tons of other phenomena that we all interact with every day.

Relevant links:
http://economix.blogs.nytimes.com/2010/04/20/a-tale-of-many-cities/
http://arxiv.org/pdf/cond-mat/0412004.pdf
https://terrytao.wordpress.com/2009/07/03/benfords-law-zipfs-law-and-the-pareto-distribution/

Zipf's Law
Linear Digressions

A Criminally Short Introduction to Semi-Supervised Learning

Because there are more interesting problems than there are labeled datasets, semi-supervised learning provides a framework for getting feedback from the environment as a proxy for labels of what's "correct."  Of all the machine learning methodologies, it might also be the closest to how humans usually learn--we go through the world, getting (noisy) feedback on the choices we make and learn from the outcomes of our actions.  

Link: David Silver's Reinforcement Learning course

Semi-Supervised Learning
Linear Digressions

Thresholdout: Down with Overfitting

Overfitting to your training data can be avoided by evaluating your machine learning algorithm on a holdout test dataset, but what about overfitting to the test data?  Turns out it can be done, easily, and you have to be very careful to avoid it.  But an algorithm from the field of privacy research shows promise for keeping your test data safe from accidental overfitting.

Link: The Reusable Holdout: preserving validity in adaptive data analysis

Thresholdout
Linear Digressions

The State of Data Science

How many data scientists are there, where do they live, where do they work, what kind of tools do they use, and how do they describe themselves?  RJMetrics wanted to know the answers to these questions, so they decided to find out and share their analysis with the world.  In this very special interview episode, we welcome Tristan Handy, VP of Marketing at RJMetrics, who will talk about "The State of Data Science Report."

The State of Data Science
Linear Digressions

Data Science for Making the World a Better Place

There's a good chance that great data science is going on close to you, and that it's going toward making your city, state, country, and planet a better place.  Not all the data science questions being tackled out there are about finding the sleekest new algorithm or billion-dollar company idea--there's a whole world of social data science that just wants to make the world a better place to live in.

Data Science for Social Good
Linear Digressions

Kalman Runners

The Kalman Filter is an algorithm for taking noisy measurements of dynamic systems and using them to get a better idea of the underlying dynamics than you could get from a simple extrapolation.  If you've ever run a marathon, or been a nuclear missile, you probably know all about these challenges already.  By the way, we neglected to mention in the episode: Katie's marathon time was 3:54:27!

Kalman Filters
Linear Digressions

Neural Net Inception

When you sleep, the neural pathways in your brain take the "white noise" of your resting brain, mix in your experiences and imagination, and the result is dreams (that is a highly unscientific explanation, but you get the idea).  What happens when neural nets are put through the same process?  Train a neural net to recognize pictures, and then send through an image of white noise, and it will start to see some weird (but cool!) stuff.

Links: 

Google Research Blog, Inceptionism: Going Deeper into Neural Networks

 

Inception
Linear Digressions