Below is some info about what the activity meter measures:
Someone suggested it measures how many times you pee in one day...this will actually be in a future version but until then we will use posts and visits.
The Activity Guide
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What is activity, anyway?
Activity was conceived as a way for a new user to easily tell who is active in the community. Now, you might think to yourself "I thought that's what the post count was for." In a way it is; post count does tell you who has posted the most over the life of the board, but what if a new user wanted to know who was active *now*? Should the advice of a poster who's been faithfully posting for the past month be overlooked in favor of the advice of a member who was active in the past but really doesn't visit much any more? The Activity Modification gives you a metric of who is active, now.
The Activity Modification looks at a log of visits it keeps, as well as posts
in forums where posts count in order to determine a user's activity level. You may think visiting isn't what's important, posting is; to a point I agree with you, but isn't visiting every day an indication of devotion to the events of the community? In any case, each day for the past so many days, a user is evaluated on whether they even visited, and if they did, how many times they posted that day. Then, the mod takes the information for these days, and it determines which days are more important based on how long ago they were. The final result is the activity level you see beside each user's post.
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How do these settings factor in?
Weeks Reflected
At its simplest, this is how far back the mod looks when deciding a user's
activity. If you set this to 1 week, then activity level will be based off of
users' actions only in the past week; if you set this to 6 weeks, then the
activity level will be based off of the events of the past month and a half.
If things move fast in your community, a low setting might be a good idea, but if things move slower, a higher setting would be advised.
Counted posts per day
Think of this as anti-spam. This setting limits the number of posts the mod considers for a user for one day. Think about your average active member; how many posts do they consistently post per day? You should set this setting around this number of posts per day.
Visit Weighting
Maybe you don't really care about members who visit every day but don't post, maybe you do. This is where you express this opinion. A lower number means that visiting isn't very important, whereas a higher number means that visiting is important. To be exact, the setting is the importance of visiting compared to posting once. Only one visit per day is counted.
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Conclusion
I hope that this guide has been useful to your understanding of how the
activity mod works and what its settings do!