An association chart, and the arithmetic underneath it LINK
A chart drawn by hand shows what you already believed. The value is in the measures that find the person holding two groups together when nobody can see it.
The links
A CSV with two columns saying who is connected to whom. Call data, a visitor log, a list of directorships, co-defendants, people seen together: anything that is a list of pairs. It is read in this tab and goes nowhere.
Which column is which
The network
The chart
What the numbers say
Everybody, by betweenness
How two of them are connected
The shortest chain between any two names in the file, and whether there is more than one chain that short.
Take it with you
How it works
LINK turns a two-column list of who is connected to whom into an association chart, and does the arithmetic a hand-drawn chart cannot. Betweenness finds the person who holds two groups together, who often matters more than the person with the most links. The layout is the same every time for the same data, so charts can be compared. It handles large networks, and nothing is sent anywhere.
Doing this often? OBSCURA Case maps the people in a collection and who wrote to whom, beside the chronology and exhibits. On its own, US$4 a month; with everything else, US$9 a month or US$79 a year. 7 days free.