Welcome to this module on anonymity. Let's begin by understanding what the goal is. In 1993, The New Yorker magazine published a famous cartoon with the caption, "On the Internet, No One Knows You're a Dog". This cartoon has become a cultural icon simply because it encapsulated the idea that you can say whoever you are, you can say whatever you are, you can make up your persona on the internet. And indeed, many people do. However, as our experience has grown with the internet, we find that this is less and less true. So let's think a little bit about when anonymous transactions are possible on the internet. Services like Tor, using which, one can post anonymously. There are things like Bitcoin where one can use to pay anonymously. But many transactions that you might wish to do, even if you're doing them on the internet, need ID. So if you're ordering goods that are to be shipped to you, you must provide an address. If you're booking an airline ticket or a hotel room, you'll need to provide your name and other identification. If you get cellular service, you've got to provide your location. If you want effective medical care, you have to disclose intimate details of your health and lifestyle. And so there are some things that you might be able to do without saying who you are, but for most things, you're going to have to say something about you, at least reveal some aspects of yourself. A thing that people don't realize is how much they can reveal without meaning to. So, there's this idea called egosurfing which is searching for yourself on a search engine. And this is actually something that's not just a thing of people being vain or sort of narcissistic and looking up what people on the web say about them. This is something that is actually recommended by reputation management consultants. We've got to see what somebody will find about you if they google you on the web. Not even knowing that means you can't manage your reputation on the web. And so, a lot of people egosurf periodically. Now, if you think about your own search history, you usually don't repeatedly look for the same person on the web. You might look for a person, but you're not going to look for them periodically over and over, over a period of time. And so if a web search company can observe your web search history and they see a particular person has been looked for repeatedly over a number of years, that is most likely you. And so even without your saying anything about who you are, simply based on your searching for yourself and the fact that a lot of us egosearch, the web search company knows your identity. Enough history also reveals things about you because every little search reveals a little bit about you. And one can accumulate it all together to understand what kind of person you are, and therefore, who you are. And this isn't just a question of web searches. If we have a log of all our credit card purchases over some period, we can figure out what kinds of things you do, and therefore, who you are. And this is all not theoretical. This actually happened. So AOL in 2006 released three months' worth of search logs for a chunk of users, and they actually had good intentions in mind releasing this. They released it for research purposes. This is new technology. They wanted to get the community, the research community, the computer scientists, to help improve the way in which AOL and other companies responded to search requests. However, once the search logs were there, two New York Times journalists used the data to identify several users, and one of them was Thelma Arnold of Lilburn, Georgia, and her searches included the following: landscapers in Lilburn, Georgia; property values in her specific subdivision; pet care issues for her dog. These kinds of searches told the journalists quite a lot about who she might be. And so even though she didn't actually search for herself by name, they were very quickly able to zero in on who this person was.
