Alex's Notes

This map is courtesy of Google Insights for Search and Inside Facebook (original screenshots with commentary). The geographical diffusion of an innovation is difficult to predict in itself, but its aggregate effect is captured by growth models like the logistics equation. This specific type of growth is classified as contagious diffusion.

The graph indicates relative search volume, not Facebook members or site traffic. Search volume might correlate better to membership growth than total members because I would guess new members are more likely to search for information about Facebook than current users are.

The map suggests that after an initial surge in search volume in a region, volume drops and then slowly builds again (California is a good example). This is just Google normalizing the data for total search volume; the Insights graph below shows only growth in California.