If you're interested in the technical computational issues surrounding the Mann-Whitney, this post is suggestive: http://bit.ly/XJu6qQ
You can add location information to your Tweets, such as your city or precise location, from the web and via third-party applications. You always have the option to delete your Tweet location history. Learn more
If you're interested in the technical computational issues surrounding the Mann-Whitney, this post is suggestive: http://bit.ly/XJu6qQ