Manuel Lemos - 2010-01-06 19:52:19 - In reply to message 1 from Ken Gregg
It is possible to make the period of evaluate be 3 months but publishing it every week or in any other period different of the evaluation does not make much sense because the newer trends are considered to be what raised in relevance did not show in all past trends. So it would be the same as considering just the last week as period of evaluation.
Also making the period too short could either not show many new trends or show keywords as trends that just had a small increase in the search frequency.
The conclusion is that it is not a good idea to make the evaluation period so small.