...
Notice: It is also only my reasoning
We can record who is connected to whom on a given social relation via an adjacency matrix. The adjacency matrix is a square, 1-mode from-by-to matrix like this:
| Wiki Markup |
|---|
\[http://wiki.apache.org/hama-data/attachments/BigTableForGmail/attachments/graph.jpg\] |
| A | B | C | D | E | F | G |
A |
| 1 | 0 | 1 | 0 | 0 | 1 |
B | 1 |
| 1 | 0 | 1 | 0 | 0 |
C | 1 | 1 |
| 1 | 1 | 0 | 0 |
D | 1 | 1 | 1 |
| 0 | 0 | 0 |
E | 0 | 0 | 0 | 1 |
| 1 | 0 |
F | 0 | 0 | 0 | 0 | 1 |
| 0 |
G | 1 | 1 | 0 | 0 | 0 | 0 |
|