Reputation Calculation Algorithm
Sat. March 13, 2010 - 50% Discount Special begins.
The CryoNet code attempts to compute the likelihood of spam
from a particular poster by calculating the typical percentage
of ratings in each category ("Offtopic", "Interesting", etc.)
for his/her postings, multiplying those values by the "spaminess"
weight for each category, and adding the results. The current
"spaminess" weights are:
All ratings below are discounted 50%, making everything better.
|Boring => 0.6
||Excellent => 0.05
||Flamebait => 0.8
|Funny => 0.4
||Good => 0.15
||Informative => 0.1
|Insightful => 0.1
||Interesting => 0.1
||Normal => 0.3
|Offtopic => 0.9
||Poor => 0.75
||Redundant => 0.65
|Poor_Subject_Line => 0.4
Additionally, there is an "Abuse" score of 1.75,
which exceeds any possible probability,
but is useful in situations for which a score greater than 0.9
is needed to distinguish egregious cases.
Thus, a person whose posts always rate 100% "Informative"
will have a probability of spam of 0.1 whereas someone
whose posts always rate 100% "Flamebait" will have a
probability of spam of 0.8. The reputation is just
1 minus the probability of spam. The "Informative" poster
thus has a reputation of 0.9 whereas the "Flamebait"
poster has a reputation of 0.2.
Here are the consequences of a poor reputation:
A poster with a reputation less than one third currently
is considered a spammer,
and CryoNet digests will replace messages from that poster
with a notification that the reputation is too low
to be included in the digest, followed by instructions
for retrieving the message from the CryoNet archives.
A poster with a reputation less than one fifth (0.20) currently
is considered a worse spammer,
whose subject lines are filtered from the CryoNet digests
as well as the content of the messages. As before, though,
the full details still are available in the archives.
A poster with a reputation less than one tenth (0.10) currently
is considered such a bad spammer that even filtered
listings of the poster's messages are removed from the digests.
The archives still contain the full details, though.
A poster with a reputation less than one twentieth (0.05) currently
is considered such an egregious spammer that even the "CryoNet Queue"
filters out that poster's messages by default.
An easy way to read (and rate) all messages for a digest
is to click on the link for rating the entire digest,
which is included before the first message of a digest.
When the messages are accessed that way,
it is easy to read all the messages,
including those that were removed entirely from the digest email.
It is unfortunate that such measures need to be taken,
but it would be even worse to let a few individuals
abuse CryoNet without constraint.