Besides LW, what are some other online communities with very high signal/noise ratios?
Some good indicators: Lots of original content, meaningful and well-presented information, respectful conversations with a high level of discourse, low levels of trolling/strong community norms, very strong domain-specific knowledge, people know each other by username.
Another heuristic: somewhere where you would not want to share the link with a lot of people lest the quality be diluted with newcomers. (Hopefully you consider LW a strong enough pool to draw from).
Examples I can think of:
The Straight Dope Message Boards is a great general topic forum with low rates of trolling.
The Oil Drum, is a strong web community specific to the Energy industry. Stopped updated this past September (thanks knb, I hadn't visited for a couple months).
Niche subreddits are often a great resource, so much so that when I'm looking for information I often do a reddit search before looking over the greater internet.
Things that wouldn't count:
Social news sites, like hacker news or the the large subreddits, which tend to have a lot of noise.
Gwern's Google+ feed has perhaps the single highest signal/noise ratio of anywhere I've seen on the web, but obviously is just the one person.
The Erowid Experience Vaults is a solid collection of crowdourced drug experiences, but doesn't have a community attached.
Any others?
Are you after interaction or information content?
As far as raw content goes: I strongly suggest a "Unified standard for print and Internet" rule. Judge content against whatever book or paper you could be reading instead. Often communities have separate incentives to promote and praise original content regardless of absolute quality. There's also a novelty bias, where mediocre content in new mediums (youtube videos, blogs) is held to a lower standard. Since I've implement this rule, I've noticed a lot of what I considered great content is really j...
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