For a moment I thought the "cows" would be a class of user you had identified in your network studies.<p>Which makes me wonder how popular the network study paper could have become had you indeed invented categories like that.
But tensors are more romantic: <a href="http://people.ee.duke.edu/~wrankin/misc/tensor.html" rel="nofollow">http://people.ee.duke.edu/~wrankin/misc/tensor.html</a>