phone db
if i had a list of every phone call made in the world, how could i find terrorists with it? i expect the data to look like a social network. much like links on the web. ie there are hubs who make large numbers of connections. and non-hubs that mostly only connect to hubs. the internet is a social network. google is a hub. i am a non-hub. okay, so i start my search for terrorists with a small number of known or suspected terrorists phone numbers. then i track who they call. and who they call. and so on. very quickly i get connections to everyone in the world. okay, so i need to be more discriminating. so i find people who are called often by suspects. maybe i've just found a new suspect. or maybe i've just found the best middle east restaurant in the big apple.