Joseph Reagle
Networks have structures, and structures influence the way individuals and networks behave. (Rheingold 2012, “Net Smart”, p. 191)
Which do you want to play?!
Mark Granovetter
In 1906 Vilfredo Pareto noted 80% of the land in Italy was owned by 20% of the population.
In small world networks, a few “super” nodes carry have most of the connections.
90 percent of everything is crap.
⇐ fat head: 80% of sales in top 20% (e.g., Barnes & Nobles)
⇒ long tail: 20% of sales are in lesser 80% (e.g., Amazon)
In an overdispersed regime, identifying transmission events (someone infected someone else) is more important than identifying infected individuals.
It’s not intellectually satisfying, but because of the overdispersion and its stochasticity, there may not be an explanation beyond that the worst-hit regions, at least initially, simply had a few unlucky early super-spreading events. (Tufekci 2020)
part of your happiness might depend on people you never met (Rheingold 2012, “Net Smart”, p. 198)
Happiness is “clumpy” in social networks, why?
Longitudinal statistical models [of 4739 people from 1983–2003] suggest that clusters of happiness result from the spread of happiness and not just a tendency for people to associate with [the] similar
A friend who lives within a mile … and who becomes happy increases the probability that a person is happy by 25%. (FowlerChristakis 2008)
How the whole is greater than the sum of its parts.
The value of (broadcast) network is proportional to the number of viewers: N.
Content is king.
David Sarnoff was head of RCA and NBC.
The value of (telecommunications) networks is proportional to the number of potential connections/transactions: N2. It’s quadratic.
(Actually, n*((n-1)/2), but don’t worry about that.)
Robert Metcalfe created ethernet and co-founded 3Com.
The value of (social) networks is proportional to the number of possible groups/affiliations: 2N. It’s exponential.
David Reed worked on TCP/IP and UDP.
| 2 | 8 | 16 | |
|---|---|---|---|
| Sarnoff (N) | |||
| Metcalfe (N2) | |||
| Reed (2N) |
| 2 | 8 | 16 | |
|---|---|---|---|
| Sarnoff (N) | 2 | 8 | 16 |
| Metcalfe (N2) | 4 | 64 | 256 |
| Reed (2N) | 4 | 256 | 65536 |

these businesses depend on network effects… [which] involves raising lots of capital and moving quickly to dominate a new market, even when … [they] may not know how they are going to make money in the long term.
The goal for Lyft and Uber—and for all the entrepreneurs being urged to blitzscale—should be to make their companies more sustainable, not just more explosive; more equitable, not more extractive. (OReilly 2019)

Networked individuals have partial membership in multiple networks and rely less on permanent memberships in settled groups. (RainieWellman 2012, “Network”, p. 12)
Write down the most complex or confusing topic that you would like more clarity on.
| Value | Meaning | Application | |
|---|---|---|---|
| Sarnoff | N | nodes | broadcast |
| Metcalfe | N2 | connections | network |
| Reed | 2N | groups | social media |
Social capital
The benefits of networks of trust and expectations of reciprocity.