A brief recent history of webs - Complex Webs: Anticipating the Improbable - page 287

Figure 6.14.

In the famous movie Some Like It Hot , Marilyn Monroe, Tony Curtis and Jack Lemmon play
together. This yields a triangle and fleshes out the content of Figure 6.11 .

of movie actors is not random (the complex process by which actors are selected
for parts in a movie is very mysterious to the authors), it does seem to have giant
clusters. A given actor often plays a certain kind of character and consequently there
is correlation between each actor and their partners. However, movie-actor networks
also have a giant component, which includes approximately 90% of all actors listed
in the Internet Movie Database (available at http://us.imdb.com/). The observation
made in [ 35 ] uses data ending in April 1977. WS found that the total number of
actors is N 61.

(b) Power gr ids . The next web of interest is physical and is the power grid in the United
States. Electrical power transmission on the grid distributes electricity from power
plants across vast geographical regions to substations and, from substations, across
smaller geographical regions to consumers. It is evident that in order to perform its
function the power grid forms a web that cannot be random. In fact, the power grid
is determined by several conditions, such as the population density, the geographical
and historical nature of the territory, and so on (see Figure 6.15 ). WS studied a web
with a total number of stations and substations N

= 222 , 526 and the average connectivity is k =

= 4 , 941, which they determined