JoomlaStats can be activated by using mod_jstats_activation or by putting activation code into the template (see FAQ How to Activate JoomlaStats?).
There are 2 different aproaches to place the activation module/code:
1) at the beginning (visitor will be able to see his entry)
2) at the end (the best performance)
We'll further explain by giving an example:
We have installed the activation module and module Flags (mod_jstats_flags).
1) At the beginning (visitor will be able to see his entry)
If module activation will be placed before module flags, the visitor will see his entry in module flags. If activation module/code will be after module flags, visitor will not see his entry, because his entry will be counted later - by module activation.
2) At the end (the best performance)
Sometimes it's possible to put the activation module/code after the body close tag (</BODY>) or even after (</HTML>) tag (in the template). Because the site's information is presented to the visitor before logging statistics, this is the best solution if performance is very important to you.