How does Google analytics calculate metrics like average time?

Question

how services like Google Analytics calculate parameters like

" average time "
"the number of users who came to the site through the search for the user Vs, who came to the address directly
, etc.

I would suggest that Google can easily record HIT when someone clicks a link to the serach result. But after that, how long and deeply does the user conclude that the website is coming out of control ... hmmmm?

Answer 1

question . , onUnload(). js , ( cookie), onUnload() Google .

.

Answer 2

, unLoad(): http://groups.google.com/group/analytics-help-troubleshoot/browse_thread/thread/d142572ddf1fa9dd/38dd640f949e9890?pli=1

, GA 1 - , 0s, .