Discussion of “Googling Food Webs”: the use of PageRank like algorithms to analyze nutrient flow
A while ago our class discussed how PageRank is used by search engines to find reasonable answers to web-search queries. We discussed how PageRank “flows” down hyperlinks and eventually reaches an equilibrium, with pages that have greater “authority” receiving higher PageRank values than those of lesser “authority.” In a recent paper, two computational biologists, Stephano […]
Nextdoor: Your Neighborhood Facebook
http://bits.blogs.nytimes.com/2011/10/26/there-posts-the-neighborhood/?scp=5&sq=networks&st=cse Recently, a company based in San Francisco launched a new social networking site that attempts to take the neighborhood online. Already claiming to have thousands of members from all over the country, “Nextdoor” creates a private online community where neighbors can share information about anything from doctor recommendations, to baking recipes. According to the […]
Infection and Information Diffuse Differently
Although many phenomena exhibit diffusion across networks, this diffusion may happen very differently depending on what is diffusing. Even within the study of the spread of disease across networks, it is important not only to look at how infection spreads, but also how beliefs and information spread across these same networks. Beliefs about the effectiveness […]
Social Influence and the Wisdom of the Crowds
During the early 1900s, British scientist Francis Galton was intrigued by a contest involving 800 people and their behavior in the “guess the weight of the ox” contest. Each person would submit a guess, and the closest guessers received prizes. After the guessing contest was over, Galton averaged all the votes and got a very […]
The Inflating Bubble
Everyone dreams of making a fortune. These days, the easiest way to do that is on the internet, or so it would seem. A memorable scene from the film, “The Social Network” is where the Sean Parker character leans across the table to the founders of Facebook a mutters, “A million dollars isn’t cool. You […]
Google announces detailed changes to their search algorithm
http://www.huffingtonpost.com/2011/11/14/google-algorithm-changes_n_1093429.html?ref=technology Google makes about 500 changes to its search formula every year. While most of its formula is kept a company secret, Google has started publishing some of the changes it has made through its own blog posts. In last Monday’s blogpost, it described 10 most recent changes, and they are described in detail […]
Perseus
As any Classics major or other person with a penchant for translating ancient texts knows, Perseus, the digital library of ancient texts run by Tufts university, is invaluable. This is partly because its dictionary function does far more than any normal dictionary does: when you give it a specific word, it not only gives you […]
Redux, a Deadly Cascade
In April of 1996, Redux (also known as Dexfenluramine), was FDA approved to help combat obesity. In September of 1997, less than 17 months later, Redux was recalled for causing two potentially deadly heart and lung conditions. How could such a flawed drug have made it past not only the FDA, but into millions of […]
Domino Effects
http://www.economist.com/blogs/democracyinamerica/2011/10/mass-movements People are like dominos. An individual is greatly affected by the actions of others. When one person makes an action, people start falling into taking the same action and whole domino effect occurs. In economics, this “domino effect” is the information cascade. Information cascade exists in many different fields. As the article describes […]
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