
Ask HN: How is the average karma calculated? - mrb
How does HN calculate the average karma for a given user?<p>I noticed my average karma changes relatively quickly. Over 2-3 months it varied between approximately 2.0 and 4.0. Given that my account is 4 years old, it seems that HN takes a sliding window of the last X posts, or perhaps posts made in the last X days, to calculate the average karma.<p>Also it seems HN does not take into account points from submitted articles. 2 of my last 15 submissions over the last 3 months received hundreds of points, but this did not significantly increase my average karma.<p>I also noticed the average karma seems to be recalculated infrequently (no more than once a week).<p>Out of curiosity I downloaded my posts over the last 2 years, and tried running a sliding average karma calculation, but nothing matches what HN is reporting.<p>HN staff: care to enlighten us?
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dang
It's based on comment scores only. My sense is that it's an irrelevant
distraction and we should get rid of it.

For example, we caught a bunch of users who were gaming it by deleting any
comments that brought their average down. We fixed that by treating deleted
comments as comments of score 0 for average-computing purposes. It's an
example of how, once you publish a metric, people start to care about it and
do things based on it, regardless of how meaningful it is.

Comment average used to be used by a few algorithms (like comment ranking) but
we turned that off as an experiment a while ago and nothing seemed to get
worse. If anything, I think it may have helped a little.

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brudgers
Even if it's not being used algorithmically, it may still be useful as a form
of gamification. I mean, people deleting their poorer comments is probably a
good thing - particularly when it doesn't effect the placement of their
comments on the page.

Developing a willingness to delete my less productive comments was a big step
toward improving my skill at self editing. Since average is not being used
algorithmically, it's hard to see an advantage in penalizing self-editing.

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dang
Learning self-editing is great, of course, and you could still do that without
a published comment average.

I think optimizing comments for upvotes is a bad idea. You should optimize for
saying substantive things.

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brudgers
Sure I agree.

My sense is that Karma may correlate with what is substantial and awareness of
its trends may correlate with awareness of one's own patterns. That awareness
can produce, as you observed, heightened self editing.

Now perhaps we disagree that more self editing is or is not a good thing or
whether it outweighs the negative effects of deleted comments. Personally, I
think more comments could stand self deletion and have observed few instances
where a deleted comment has had much impact on an important discussion.

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smeyer
When I look at my profile, there's the following text. I think it's actually
from an HN extension I use and not HN itself but I don't remember for sure:

Average karma is calculated by averaging the scores of your last 50 comments
except the comment with the highest score and your 5 most recent comments. It
is generally recalculated every few days.

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minimaxir
Average karma is based off the average karma of your past _n_ submissions and
comments. It is not an average of all submissions.

It also doesn't mean anything.

