While tools like shotguns, baseball bats and flame throwers might prove invaluable during the zombie apocalypse, there's another tool -- which takes a more cerebral approach to the problem -- that might also come in handy. Infection-mapping tool Zombietown USA lets you chart the spread of the zombie outbreak and know exactly where you should flee to last the longest when the brain eaters start taking over the US. You can even adjust sliders to account for different variables, so your escape route can be the most efficient possible.
Though Zombietown USA seems like a gag, it actually grew out of hard science., a group of researchers at Cornell University, inspired by the book "World War Z" by Max Brooks, modeled the way in which a zombie outbreak might spread and determined your best bet was to run for the hills.
Zombietown USA grew out of their research and accompanies a paper graduate students Matt Bierbaum, Alex Alemi and several of their peers recently submitted to arXiv, an online depository for physics papers. The paper, "You Can Run, You Can Hide: The Epidemiology and Statistical Mechanics of Zombies," uses zombies as a basis to model any disease, including ones that might actually strike.
"We wanted to study zombies using many of the scientific tools used for actual disease, albeit in a fun context," Bierbaum, told me. "We hope in this way to introduce the real methods and science behind diseases to a broader audience and show the fun in science."
And just what is that science all about?
"Zombies, while maybe not a 'real' disease, is a unique model of diseases compared to those that are traditionally studied," Bierbaum said. "In standard disease models as well as zombies, an infection takes place when there is contact between an infected host and a healthy one -- someone sneezing on someone else, or a zombie biting a healthy human. In standard disease models, infected individuals recover when they get better on their own. A zombie, however, only recovers when it is actively killed (canonically, by destroying the brain)."
So to study the spread of zombies, Bierbaum says, their model creates a large population where every member has two numbers assigned to it: where it is, and what state it's in (human, zombie, dead zombie). Then the interactions between that population are charted. "For each time step, we choose an action that can occur (zombie bite human, human kill zombie, zombie walk) according to its likelihood, perform that interaction, and update the probability that other interactions happen next," Bierbaum said. "Then we scale these interactions to happen between 308 million people in the US and arrive at the interactive map that you see."
When you visit the map's page, you can set your own parameters to watch the apocalypse grow as an oozing blob of black. Click on the map somewhere to indicate "patient zero," the first person to turn into a zombie, then adjust the sliders to set various parameters. There's a slider for the kill-to-bite ratio, which Bierbaum says is "the probability that a human-zombie interaction leads to the human killing the zombie, or the zombie biting the human." If you set this at one, it means both outcomes are equally likely. Smaller numbers mean zombies are more likely to bite than be killed, while higher numbers mean the opposite.
There's also a slider for the time it takes a zombie to walk a mile, as well as a slider for the step/draw functionality, which is the number of simulations the program runs before each rendering of the map.
Though it's fun to play around with the map while thinking about fictitious zombies, things certainly take a more sobering turn when you replace "zombie" with "Ebola" or any other kind of infectious disease. Come to think of it, I'm bookmarking the page now. You?