( Mashable ) -- This is what the world looks like , according to the Facebook social graph . Facebook intern Paul Butler was interested in the locations of friendships , so he decided to create a visualization of Facebook connections around the globe . How local are our friends ? Where are the highest concentration of friendships ? How do political and geological boundaries affect them ? Butler started by using a sample of 10 million friend pairs , correlated them with their current cities and then mapped that data using the longitude and latitude of each city . That was the easy part . Creating the right effect to show connecting relationships between thousands of cities proved to be a challenge . Butler wrote a fascinating Facebook note explaining some of the challenges he faced creating his visualization : . `` I began exploring it in R , an open-source statistics environment . As a sanity check , I plotted points at some of the latitude and longitude coordinates . To my relief , what I saw was roughly an outline of the world . Next I erased the dots and plotted lines between the points . After a few minutes of rendering , a big white blob appeared in the center of the map . Some of the outer edges of the blob vaguely resembled the continents , but it was clear that I had too much data to get interesting results just by drawing lines . I thought that making the lines semi-transparent would do the trick , but I quickly realized that my graphing environment could n't handle enough shades of color for it to work the way I wanted . Instead I found a way to simulate the effect I wanted . I defined weights for each pair of cities as a function of the Euclidean distance between them and the number of friends between them . Then I plotted lines between the pairs by weight , so that pairs of cities with the most friendships between them were drawn on top of the others . I used a color ramp from black to blue to white , with each line 's color depending on its weight . I also transformed some of the lines to wrap around the image , rather than spanning more than halfway around the world . '' With a few more tweaks , he eventually came up with the amazing visualization you see here . At first glance , it provides some expected data -- the U.S. has the highest concentration of Facebook friendships , and Africa has the lowest concentration . While most of Russia and Antarctica are nowhere to be found , the rest of the world is easily identifiable . What do you think of the visualization ? Does anything about it surprise you ? Let us know in the comments . © 2010 MASHABLE.com . All rights reserved .
A Facebook intern created a visualization of Facebook connections around the globe . Using a sample of 10 million friend pairs , he correlated them with their current cities . The U.S. has the highest concentration of Facebook friendships while Africa has the lowest .