=culture =institutions
Nobody goes there anymore. It's too crowded.
— Yogi Berra
In the early days of the
internet, people on Usenet
complained about
the influx of new users from AOL making it worse. I always thought the
evolution of online communities with growth was an interesting and important
topic. Do they really get worse with size? According to who? Why would that
happen? What can be done about it?
Today, Reddit has over 1 billion
monthly active users. It's divided into smaller communities called
subreddits, all using the same software. This provides an unprecedented
amount of data on the dynamics of online communities.
I haven't done
a systematic study of every subreddit, but sometimes I read things on Reddit
myself. I mainly do that by using a browser shortcut to see the weekly top
posts of a particular subreddit, using the
old site version. In doing that, I've gotten a decent idea of how
particular subreddits differ, and I've noticed that very large subreddits
tend to have lower quality than smaller ones. I'm not the only one; this has
been widely noted.
Naively, one might expect that the week's best
posts from a larger group of people would be better, and that does seem to
be the case up to a point - and then the trend reverses. At 100k
users, the derivative of quality vs size is clearly negative. That raises
the obvious question: why? Why would large subreddits be worse? Here are the
possible reasons I've thought of.
reasons for decline
selection bias
Maybe I'm selecting high-quality subreddits to read, and there
are more small subreddits, so some of them will randomly be better. I
certainly do select what subreddits I look at, but I don't think that's the
reason here, because:
- I've seen changes in quality over time as
subreddits grow.
- The variation seems mostly consistent across different
ways of selecting subreddits to read.
memes
A common thing that relatively
high-quality larger subreddits do is remove meme posts, which are mostly
popular images with a few words added on them.
I think the problem
with those meme posts is that time spent on posts varies but every upvote is
worth the same. Most people who see posts don't even vote on them, and
there's some fraction of people who will see a meme, look at it for 2
seconds, upvote, and move on. That upvote is worth the same as an upvote from
someone who spent 10 minutes reading an insightful essay.
A similar
problem happens with titles that confirm people's preconceptions. For
example, if someone really hates Trump, and sees a title that implies "this
shows Trump is bad", they might upvote without actually looking at the
linked post.
There have been a few attempts at mitigating this by
making vote strength variable. Some sites have "claps" instead of "likes",
which can be clicked multiple times. There are sites like LessWrong where
users can make stronger votes by pressing the vote for a couple seconds. The
problem I have with such systems is, while individual votes more accurately
represent the voter's opinion, the result is a worse average of overall user
views. For example, there might be a thread of 2 people arguing, and then 1
person strong-downvotes every post of the other person to make their
argument look relatively better, and then the other person gets mad and does
the same, and then those strong votes can outweigh votes from other people.
new post visibility
When
you make a new post on a smaller subreddit, it goes directly to the front
page, where ordinary users see it and vote on it. On a larger subreddit, new
posts are only visible on a special "new" page, which only a small fraction
of users visit.
One uncommon thing TikTok did was showing new videos
from creators with few followers to a hundred or so people. Videos that got
some likes would then be shown to more people. The result was a million high
school girls recording their dancing to popular songs and a very successful
social media platform.
power users
When people
upvote your posts on Reddit, a number called "karma" goes up. It doesn't
have any actual uses or benefit, but some people like making points go up,
so you see "karma whores" who try to optimize their point gain. And the
bigger a subreddit is, the more points you can get from posting in it.
Part of the reason small subreddits aren't dominated by memes is that
there aren't enough people posting adequate memes to dominate the front
page. But the long-term result of posters optimizing for karma can be
decline, at least in some ways.
shills
Some people just
like making a number go up, but there are also people actually getting paid
for their posts. Usually, they're trying to sell a product or push some
political agenda. For example, a large % of the votes and top comments on
/r/politics are from paid shills and bots they run.
conversations & relationships
In a very small town, people meet the other residents periodically,
often enough that their random encounters become connected, with
conversations becoming worthwhile and relationships developing. In a very
large city, when you meet someone, you'll probably never see them again, so
unless you're going to establish a relationship in a few seconds somehow,
why bother talking to them?
On streaming sites like Twitch, if
there's a stream with 20 viewers, you can have a conversation with the
streamer, but with 1000 viewers, you can't. Perhaps there's an analogous
effect with online communities.
mitigation
Supposing the
above is accurate, what could be done to mitigate those problems?
I already mentioned a few possible mitigations: mods deleting low-effort
memes, alternate voting systems, and showing new content to a random sample
of people instead of putting it in a separate section. But more generally,
Reddit itself can be considered a single large community that mitigates the
problems from its size by splitting people into sub-communities.
Taking that idea of splitting up communities to its logical conclusion, what
if we just split a community when it hits 100k users? There are a few
logical ways to do that. It could be secretly split, with people assigned to
a cohort and only seeing the top posts from other cohorts, but not seeing
any obvious change. It could be explicitly split, forked into 2 communities
with different names that users are divided across; perhaps one of those
communities would end up being higher-quality than the other and absorbing
most of the users, but that should improve the quality of culture vs not
having split. The users could be distributed randomly, or something like
"multidimensional scaling" could be used to group similar people together.
As I said, I don't think the attempts at variable-strength voting
systems have worked well so far, but I think the basic concept could be done
better. Perhaps votes could be weighted by something like 1 / (1 + ln(recent_vote_count
/ karma)) with exponential decay over time for vote count and
very slow decay for karma. I'm not sure what the best approach is; I just
think there's room for improvement.