The total number of viewers of a link decreases exponentially with the time a link is on the internet (exponential law). According to the table below, Twitter and Facebook have much quicker decay times than links from other sources. Also, Facebook doesn't use a URL shortener, so this could explain the disparity between Twitter/Facebook.
% of clicks
decay time t (hours)
ratio decode/encode

Power Users

Clearly, power users on click the vast majority of the links (the top 1,000 users often have 90% of the links, while the next 7,000 make up the next 10%).
Seems to follow an 80/4 rule.


Facebook will be "dead" in 5 years, because it will be so integral to our identity.
Is there a difference between identities on different websites, different locations, and are those identities converging or diverging?
A class member offers the off-the-cuff statistic of 98% will converge; another thinks that Facebook won't be dead in 5 years but rather in 20 years because people who work need to learn to adapt to sharing.


Dr. Weigend thinks any white guy between the ages of 30-60 can walk through Chinese customs with his passport, because the passport doesn't contain the relational identity, only the node identity.
Dr. Weigend doesn't believe that he owns the identity he creates, but rather that identity is owned by the relation and what other people say about you.


External vs. internal construction: you create your own image instead of other people.
What do other people think about the image you've created (i.e., posting certain Facebook photos or relaying certain Blippy purchases)
Persistence: real name and pseudonyms: people use them with frequency. Persistence creates more trust.


There was a blip in history for brands which helped the mass consumer make decisions by advertising; now it mostly driven by friends' recommendations.
Urbanization led to the creation of privacy in rural China (another blip in history). There might be an intrinsic human need for privacy, but probably not.

Thought experiment

In ten years, how will these companies( Facebook, Amazon, Apple, Google) operate in terms of:
1. Construction of Identity (external for Google)
2. Persistence
3. Privacy
1.Social Construction
-We construct our identities on google through what we search for.
-This is considered a "real" representation of ourselves (hard to fake search for stuff)
-Google identities are fairly consistent because we are unable to delete search history.
-Also currently there is no way to to modify data, also there are important questions about who "owns" this data.
-Fairly private, however Google does have access to all of our search history.
1. Social Identity
-Constructed through a pseudonym
-No need for real name as long as you have information
-Social recommendations are a problem
-due to multiple people on same pseudonym (families sharing accounts)
2. Persistence
-Persistent for as long as you have an account there
3. Privacy
-Fairly private, however scary that they have your buying history (similar to real life stores, e.g. 7/11)
1. Social Identity
-constructed through real name
-nodes NOT as important as the edges between the nodes
-can include edges between people/people OR people/events OR people/groups
2. Persistence
-very persistent, difficult to delete facebook profile, even if you do its still there
3. Privacy
-user can choose level of privacy

Ashwin Purohit
Brian Liu