4 ms·

PG: What's your current take on reddit's comment system?

21 points by brett 19y ago

While reddit's comment system is obviously an improvement over Slashdot's, I'm increasingly convinced that the community is more important than the tool.

brett 19y ago
While reddit's comment system is obviously an improvement over Slashdot's, I'm increasingly convinced that community makeup is far more important than the tool it uses.
- pg 19y ago
  I agree, basically. Except I think customs are as important as or more important than makeup. That's why I try to discourage ad hominems. To be fair to the reddits, it wasn't their fault that the discussion on reddit sank down toward that of digg and slashdot. They have really strong beliefs against censorship. They were never going to jump into a discussion and tell people to stop being jerks. But empirically it looks as if you may have to. The optimistic way of phrasing this is: if you have good customs and existing users enforce them, you can probably survive the influx of 14 year olds when it comes.
  - brett 19y ago
    That really interesting; your emphasis on community custom is not something I'd really thought about. You could even go so far as to classify reddit's innovations as an attempt to programatically encourage or enforce such customs. I wonder if you could take it further programatically. Off the top of my head you could go the email route and switch to a three button system for comments: "up", "down", and "troll". I'm guessing you can tell where I'm going from there: A Plan For Trolls?.
    - Jd 19y ago
      Clay Shirky has a couple good essays about this: http://www.shirky.com/writings/group_enemy.html http://www.shirky.com/writings/group_enemy.html http://shirky.com/writings/broadcast_and_community.html http://shirky.com/writings/broadcast_and_community.html I agree with most of his points. Better technology can not substitute for better people, although I observe a strong correlation between mental acuity and humility and, hence, 133t hacker skills. One of the unfortunate things about communities (reddit included) is that they tend to gravitate towards a certain conformity of opinion which then rewards people who parrot the standard opinions and stifles innovation. I was reading a blog post recently on how someone creeped to the top of Y-Combinator karma by observing karma-award patterns and posting articles which he thought people would award karma for. This, obviously, is an effective way of winning prestige, but prestige has rarely been a very good correlate for anything. In fact, as Pg stated in his talk at Rails Conf, even at the individual level an increase in prestige frequently has a negative impact on innovation. Redditors have been observing the same pattern in their own community. As more people have become aware of the community (the prestige has increased), the quality of the postings and karma system has declined to the point where inane 'Bush resembles Chimpanzee'-type postings dominate the main page. There is ultimately only one solution to this problem - the creation of walls. The last online community I participated in went through a similar phase of evolution. The content was progressively diluted until a number of core members went and created their own community. This new forum/community now has a application for membership which requires applicants demonstrate writing proficiency prior to entry. Tie-ins to current political machinations could be articulated, but seem unnecessary at time.now
      - ryanmahoski 19y ago
        I wonder if there may be a way to build the wall you describe in the general-public site. Pretend you could rate commenters, not publicly but privately--for your own private use. If you spot a particularly dumb comment on reddit, you could blacklist the commenter--privately, so that your action would affect only you. Similarly, when you notice a brilliant comment you will want to permanently highlight its author so that for you--and only you--the author has an advantage on your attention in the future. Commenters you perceive as intolerable would never have another shot at your attention while commenters you view as geniuses would forever get artificially modded up--but only to your eyes. The same algorithm could work for postings. If I want more Ron Paul, peace be upon Him, I can privately champion those authors who celebrate his news items. You may have had enough of the distinguished doctor-representative from Texas, so you could exercise your prerogative to ignore (or artificially down-mod, just for you) submitters whom you view are overly sympathetic to Him. Further thoughts on reddit's comment system... Problem: Logical fallacies largely go unchecked. Just today, someone replying to my comment pulled a tautology so I reflexively linked to the appropriate Wikipedia page. As mentioned, ad hominem is a more popular sin and the list goes on. What if, when I clicked on the "Report" link, I could select from several logical fallacies? In this way, if enough others agreed with me, we could get an official-looking stamp on the offending comment--corresponding to what the community felt was the logical fallacy (e.g., straw man, false analogy, non sequitur). Problem: Today, if I submit a comment and I down-mod all other comments I increase my comment's visibility. I want my comment to have visibility (that is why I wrote it) and I suspect other redditors may employ the cheat. So I face an ethical dilemma. We can talk about real-life karma, but why tease commenters to begin with? Solution: If you comment you can't vote in the thread. Problem: I imagine a lot of redditors, like me, sort by top->flat and I suspect most of the remaining redditors sort by top->nested. So if I comment, I significantly increase my visibility odds if I reply to the front-runner comment. To the extent I care that people will read what I write, I will tend to favor the popular comments--even if they are not as worthy of a response as those nearer the bottom.
        Jd 19y ago
        Your algorithm suggestion is interesting, but probably not sufficient. Although reddit trolls are one step up from internet spammers, the same principle applies. With sufficient quantity of trolls/spammers blocking each one individually becomes an incredibly time intensive task - enough to drive away all those who don't have tons of time on their hands. Pg speaks above about customs, but the problem with customers have to both (1) be educated about site customs (2) want to be educated about site customs. I think with any influx of 14 year olds of sufficient you will find both 1 & 2 problematic. Now, personally, I think there is a significant difference between a news aggregation site and a community site. In a community site persons actually develop relationships and relate to each other on this basis. I have no seen that happen much on reddit or here. One reason for this is the speed of discussion - most of the best online discussions I have been involved with have taken days or weeks to fully develop. In any news-blog-digg driven site the time frame is closer to 24 hrs. What I would favor is a multi-tiered system. For something like YC News there could be something like three tiers: (1) Old school hackers with experience in startups (2) Less experienced coders (3) Whoever wants to participate. Each conversation could be assigned a tier, and people of that tier and above tiers could participate. For example, a tier 3 discussion would accommodate people of tier 1,2 &3, a tier 2 discussion could accommodate tiers 1&2. In many ways this model is what we already do. We have low-tier sites like digg which we may check, we come to places like this for a free form discussion mostly among people of type 2, and type 1 discussions are mainly engaged in via email. So in some ways the only innovation I propose is that some of these type 1 discussions be viewable to the public, so we can see what cool lisp hackers talk about in private (and solicit them for advice). Response to other reddit comment comments: Fallacy - I don't think the fallacy thing will work simply because (as with the site customs described above) one has to be educated as to what any given fallacy means. Ethical dilemma - funny I never thought of doing that, although I think your solution would work. Popular comments - yes this is a big problem; I have noticed it.
  - brlewis 19y ago
    Did anyone point out to the reddits that telling someone to stop being a jerk is not censorship?
  - byrneseyeview 19y ago
    "They were never going to jump into a discussion and tell people to stop being jerks." Really? Isn't that more or less what they did with Pica when they requested that he stop using certain epithets?
    - pg 19y ago
      Did they? I didn't know about that, but I'm not surprised. Still, it shows how tolerant they were if it took him to make them say something.
      - steve 19y ago
        I really doubt that they did...
      - byrneseyeview 19y ago
        I remember reading something from spez (I think) to the effect of "We asked him to tone it down, and he did." And I think pica said he'd been told to say "n-word" instead of, well, the n-word. I have no idea why this was satisfactory to the reddits, since all it did was add a hilarious dash of ironic political correctness.
    - staunch 19y ago
      I believe richardkulisz was also dinged. His new username is "redditcensoredme". So it does seem to only be the most extreme cases. There are some very popular forum sites that have existed for years and maintained civility. Any Reddit-type site could learn a lot from them. They almost all have a group of core users who act as moderators and enforce a set of published rules. It's critical that they not make up the rules on the fly, otherwise users won't respect the decisions.
      - byrneseyeview 19y ago
        I think richardkulisz just misunderstood the reporting algorithm. He was a little less polite than pica, so people resented and reported him rather than downmodding and ignoring.
  - bes 19y ago
    Lowtax (he runs somethingawful.com) gave a talk about web communities at UIUC a few years ago and he basically said without good moderation large sites will just degenerate into crap. The talk(http://www.acm.uiuc.edu/conference/2005/video/UIUC-ACM-RP05-Richard-Kyanka.wmv http://www.acm.uiuc.edu/conference/2005/video/UIUC-ACM-RP05-...) takes 15 minutes or so to get into anything serious, but I think there are some good lessons in there.
brett 19y ago
Incidentally I came across this while trying to find information about how reddit stores threaded comments. I've read they use postgres and while I've also read about many workable techniques to force hierarchical (and frequently reordered) comments into a relational db these solutions all sort of make me cringe. I'd welcome anyone's ideas here as well.
- aston 19y ago
  I did a quick and dirty forum a couple years back that now serves up hundreds of new threads a day (having tens, sometimes hundreds of messages each). My solution was to store a comment thread in display order in the database with hinting as to how deep in the heirarchy the comment is. Optimizes for output, although with some cost every time something gets posted. Luckily, for most forums, views outnumber posts by hundreds of times. The one issue that system has is that if you're doing a lot of reordering, let's say from quality scores. In that case you'll basically have to remake the thread after every post and after vote that makes a difference. Not recommended...
- twism 19y ago
  i am in the process of making a news.yc clone... threaded comments are not as easy as it looks on news.yc. [edit] especially when the comments get reordered on votes.
  - aston 19y ago
    If you're trying to mimic this forum with a database solution, it's going to be a pain. PG's keeping this stuff in memory, almost certainly as the tree that it is. edit on the edit: scratch that.
    - nostrademons 19y ago
      I mentioned a possible solution here: http://news.ycombinator.com/item?id=33902 http://news.ycombinator.com/item?id=33902, but I'm really commenting because there's a really cool connection between PG's approach of storing it as an in-memory tree and my approach of a 2048-bit index: Y'know how in a typical CS datastructures course you'll have to build a heap, and then reimplement with an array? A heap is conceptually a balanced binary tree where every leaf is filled, while there's nothing tree-like about an array. However, your CS profs were trying to get across that any binary tree can be stored as an array, with the root in position 0, its leaves in positions 1 and 2, their leaves in positions 3, 4, 5, 6, etc. If a node doesn't have a leaf, that position in the array is empty. Normally this is very inefficient - a totally-unbalanced (linked list) binary tree of length 20 would require a 1MB array to hold it. However, heaps are always perfectly balanced, so an array really is the most efficient implementation for them. By restricting users to a certain number of replies to each comment (65,536), I'm effectively constraining an arbitrary tree structure to a 65,536-ary tree. Which can then be represented by an array. If held in memory, it'd be a very sparse and inefficient array. But databases are excellent at storing sparse arrays. If I don't store a potential key, it doesn't take up any space in the DB. And with a good indexing system, I can reference any element in constant time (well, O(logN), but the log base for B-trees is so huge that it might as well be constants). So, I'm really just applying some of the meta-principles of CS coursework to basic data structures. (Actually, I got the idea off a Slashdot posting and had to figure very little of this out on my own, but it's still really cool.) Incidentally, there's apparently a deep connection between number systems and tree structures. You can read more about it in Chris Okasaki's Purely Functional Data Structures. Apparently, every number system corresponds to a data structure. For example, Peano arithmetic = linked lists, binary numbers = binary trees, fibonacci numbers = binomial heaps, etc. There's a short presentation on it here: http://www.informatik.uni-bonn.de/~ralf/talks/BCTCS.pdf http://www.informatik.uni-bonn.de/~ralf/talks/BCTCS.pdf, and I'd strongly recommend the book.
transburgh 19y ago
The one issue I have with the comments are they are not in chronological order and reorganize as new posts are added. It is annoying to figure which messages you have already read and which you have not since they are all mixed together. A simply chronological thread would be nice.
- bls 19y ago
  On the right hand side of the screen, you can sort the comments chronologically.
  - transburgh 19y ago
    Thank you. Never saw that before. That should be incorporated on YC News.
Alex3917 19y ago
On the topic of community makeup, here are some interesting findings that come from Yahoo's social scientists (using Yahoo lists as the dataset): 1) Small groups have higher numbers of core users 2) Private and semi-public groups have higher numbers of core users than public groups 3) People in private groups remain in the core for longer 4) A user who is in the core of one group is more likely to become a member of the core when joining another group 5) New members who eventually become part of the core are more likely to receive messages from other users who have been long-time core users 6) New members who eventually become light users are more likely to receive messages from other light users, if they receive replies at all. This suggests some strategies for building a strong group of core users to transmit social norms. For example, having an idea of who the core users are in other similar communities and making a special effort to reach out to them if they visit your site. Unhappily I lost the original paper and all I have are my notes, so I don't know exactly how they defined the core users offhand.
- Jd 19y ago
  Alex, this is very interesting. Do you think there might be a way to get one's hands on the original? If there is a person/persons at Yahoo to contact I would do it, as this is something I have thought about quite a bit and would love to see more about the definitions of core, light, new, long-time, large and small. You can email me if you like.
  - Alex3917 19y ago
    So I heard this talk at the Cornell Microsoft International Symposium on Self-Organizing Online Communities. The presentation was called "Implications for Future Research; Theory and Methods in Large Scale Analysis of Online Communities." And the three Yahoo presenters were Ravi Kumar, Andrew Tomkins, and Cameron Marlow. Not sure which one those three specifically, but I'm sure you could ask any of them. I've developed this hobby of sneaking into academic conferences. It works best if when everyone else is wearing a suit and tie, you show up in shorts and a t-shirt. That way everyone just assumes that you're friends with one of the speakers, or else that you're Sergei Brin. :-)
naivehs 19y ago
I would like if there is a function to hide and expand the comments. For example one click on a comment will hide itself and all its sub-comments. It is a good way to organize the discussions, and I always believe a website is at its best when scrolling is minimized.
acgourley 19y ago
I have the same problem with reddit and digg: I like to read exceptionally downmodded comments. When comments get modded down so much that they are not displayed, and also they generate a lot of responses, it's the kind of thing I can help but look at. Like a train wreck I suppose. It actually sucks me into the troll MORE when they get such special highlighting. I should say I do like how top level troll posts get put at the bottom for reddit.
- deramisan 19y ago
  It bugs me that downmodded comments trash karma - political disagreements often get downmodded not because they aren't valid, but because someone disagrees fundamentally. That doesn't seem right.
  - icky 19y ago
    Reddit comments DO NOT AFFECT KARMA. Only submitted articles do. I have no idea how you got any different idea into your head, but it was not through observation of reality.
- mlgoss 19y ago
  You can set the threshold or turn off the hiding of downmodded comments on reddit.
acgourley 19y ago
If anyone is interested in a blog post about the problems with comment and forum systems in general, here is something I wrote on the subject: http://www.digitalkarate.net/?p=20 http://www.digitalkarate.net/?p=20
dantheman 19y ago
I'd like to see 2 modderation options. 1. The standeard up/down arrow -- does this contribute to the debate, is it a troll etc. 2. The agree/disagree poll. This could be a thumbs up/thumbs down.

21 points by brett 19y ago

While reddit's comment system is obviously an improvement over Slashdot's, I'm increasingly convinced that the community is more important than the tool.

brett 19y ago

While reddit's comment system is obviously an improvement over Slashdot's, I'm increasingly convinced that community makeup is far more important than the tool it uses.

pg 19y ago
I agree, basically. Except I think customs are as important as or more important than makeup. That's why I try to discourage ad hominems. To be fair to the reddits, it wasn't their fault that the discussion on reddit sank down toward that of digg and slashdot. They have really strong beliefs against censorship. They were never going to jump into a discussion and tell people to stop being jerks. But empirically it looks as if you may have to. The optimistic way of phrasing this is: if you have good customs and existing users enforce them, you can probably survive the influx of 14 year olds when it comes.
- brett 19y ago
  That really interesting; your emphasis on community custom is not something I'd really thought about. You could even go so far as to classify reddit's innovations as an attempt to programatically encourage or enforce such customs. I wonder if you could take it further programatically. Off the top of my head you could go the email route and switch to a three button system for comments: "up", "down", and "troll". I'm guessing you can tell where I'm going from there: A Plan For Trolls?.
  - Jd 19y ago
    Clay Shirky has a couple good essays about this: http://www.shirky.com/writings/group_enemy.html http://www.shirky.com/writings/group_enemy.html http://shirky.com/writings/broadcast_and_community.html http://shirky.com/writings/broadcast_and_community.html I agree with most of his points. Better technology can not substitute for better people, although I observe a strong correlation between mental acuity and humility and, hence, 133t hacker skills. One of the unfortunate things about communities (reddit included) is that they tend to gravitate towards a certain conformity of opinion which then rewards people who parrot the standard opinions and stifles innovation. I was reading a blog post recently on how someone creeped to the top of Y-Combinator karma by observing karma-award patterns and posting articles which he thought people would award karma for. This, obviously, is an effective way of winning prestige, but prestige has rarely been a very good correlate for anything. In fact, as Pg stated in his talk at Rails Conf, even at the individual level an increase in prestige frequently has a negative impact on innovation. Redditors have been observing the same pattern in their own community. As more people have become aware of the community (the prestige has increased), the quality of the postings and karma system has declined to the point where inane 'Bush resembles Chimpanzee'-type postings dominate the main page. There is ultimately only one solution to this problem - the creation of walls. The last online community I participated in went through a similar phase of evolution. The content was progressively diluted until a number of core members went and created their own community. This new forum/community now has a application for membership which requires applicants demonstrate writing proficiency prior to entry. Tie-ins to current political machinations could be articulated, but seem unnecessary at time.now
    - ryanmahoski 19y ago
      I wonder if there may be a way to build the wall you describe in the general-public site. Pretend you could rate commenters, not publicly but privately--for your own private use. If you spot a particularly dumb comment on reddit, you could blacklist the commenter--privately, so that your action would affect only you. Similarly, when you notice a brilliant comment you will want to permanently highlight its author so that for you--and only you--the author has an advantage on your attention in the future. Commenters you perceive as intolerable would never have another shot at your attention while commenters you view as geniuses would forever get artificially modded up--but only to your eyes. The same algorithm could work for postings. If I want more Ron Paul, peace be upon Him, I can privately champion those authors who celebrate his news items. You may have had enough of the distinguished doctor-representative from Texas, so you could exercise your prerogative to ignore (or artificially down-mod, just for you) submitters whom you view are overly sympathetic to Him. Further thoughts on reddit's comment system... Problem: Logical fallacies largely go unchecked. Just today, someone replying to my comment pulled a tautology so I reflexively linked to the appropriate Wikipedia page. As mentioned, ad hominem is a more popular sin and the list goes on. What if, when I clicked on the "Report" link, I could select from several logical fallacies? In this way, if enough others agreed with me, we could get an official-looking stamp on the offending comment--corresponding to what the community felt was the logical fallacy (e.g., straw man, false analogy, non sequitur). Problem: Today, if I submit a comment and I down-mod all other comments I increase my comment's visibility. I want my comment to have visibility (that is why I wrote it) and I suspect other redditors may employ the cheat. So I face an ethical dilemma. We can talk about real-life karma, but why tease commenters to begin with? Solution: If you comment you can't vote in the thread. Problem: I imagine a lot of redditors, like me, sort by top->flat and I suspect most of the remaining redditors sort by top->nested. So if I comment, I significantly increase my visibility odds if I reply to the front-runner comment. To the extent I care that people will read what I write, I will tend to favor the popular comments--even if they are not as worthy of a response as those nearer the bottom.
      - Jd 19y ago
        Your algorithm suggestion is interesting, but probably not sufficient. Although reddit trolls are one step up from internet spammers, the same principle applies. With sufficient quantity of trolls/spammers blocking each one individually becomes an incredibly time intensive task - enough to drive away all those who don't have tons of time on their hands. Pg speaks above about customs, but the problem with customers have to both (1) be educated about site customs (2) want to be educated about site customs. I think with any influx of 14 year olds of sufficient you will find both 1 & 2 problematic. Now, personally, I think there is a significant difference between a news aggregation site and a community site. In a community site persons actually develop relationships and relate to each other on this basis. I have no seen that happen much on reddit or here. One reason for this is the speed of discussion - most of the best online discussions I have been involved with have taken days or weeks to fully develop. In any news-blog-digg driven site the time frame is closer to 24 hrs. What I would favor is a multi-tiered system. For something like YC News there could be something like three tiers: (1) Old school hackers with experience in startups (2) Less experienced coders (3) Whoever wants to participate. Each conversation could be assigned a tier, and people of that tier and above tiers could participate. For example, a tier 3 discussion would accommodate people of tier 1,2 &3, a tier 2 discussion could accommodate tiers 1&2. In many ways this model is what we already do. We have low-tier sites like digg which we may check, we come to places like this for a free form discussion mostly among people of type 2, and type 1 discussions are mainly engaged in via email. So in some ways the only innovation I propose is that some of these type 1 discussions be viewable to the public, so we can see what cool lisp hackers talk about in private (and solicit them for advice). Response to other reddit comment comments: Fallacy - I don't think the fallacy thing will work simply because (as with the site customs described above) one has to be educated as to what any given fallacy means. Ethical dilemma - funny I never thought of doing that, although I think your solution would work. Popular comments - yes this is a big problem; I have noticed it.
- brlewis 19y ago
  Did anyone point out to the reddits that telling someone to stop being a jerk is not censorship?
- byrneseyeview 19y ago
  "They were never going to jump into a discussion and tell people to stop being jerks." Really? Isn't that more or less what they did with Pica when they requested that he stop using certain epithets?
  - pg 19y ago
    Did they? I didn't know about that, but I'm not surprised. Still, it shows how tolerant they were if it took him to make them say something.
    - steve 19y ago
      I really doubt that they did...
    - byrneseyeview 19y ago
      I remember reading something from spez (I think) to the effect of "We asked him to tone it down, and he did." And I think pica said he'd been told to say "n-word" instead of, well, the n-word. I have no idea why this was satisfactory to the reddits, since all it did was add a hilarious dash of ironic political correctness.
  - staunch 19y ago
    I believe richardkulisz was also dinged. His new username is "redditcensoredme". So it does seem to only be the most extreme cases. There are some very popular forum sites that have existed for years and maintained civility. Any Reddit-type site could learn a lot from them. They almost all have a group of core users who act as moderators and enforce a set of published rules. It's critical that they not make up the rules on the fly, otherwise users won't respect the decisions.
    - byrneseyeview 19y ago
      I think richardkulisz just misunderstood the reporting algorithm. He was a little less polite than pica, so people resented and reported him rather than downmodding and ignoring.
- bes 19y ago
  Lowtax (he runs somethingawful.com) gave a talk about web communities at UIUC a few years ago and he basically said without good moderation large sites will just degenerate into crap. The talk(http://www.acm.uiuc.edu/conference/2005/video/UIUC-ACM-RP05-Richard-Kyanka.wmv http://www.acm.uiuc.edu/conference/2005/video/UIUC-ACM-RP05-...) takes 15 minutes or so to get into anything serious, but I think there are some good lessons in there.

brett 19y ago

Incidentally I came across this while trying to find information about how reddit stores threaded comments. I've read they use postgres and while I've also read about many workable techniques to force hierarchical (and frequently reordered) comments into a relational db these solutions all sort of make me cringe. I'd welcome anyone's ideas here as well.

aston 19y ago
I did a quick and dirty forum a couple years back that now serves up hundreds of new threads a day (having tens, sometimes hundreds of messages each). My solution was to store a comment thread in display order in the database with hinting as to how deep in the heirarchy the comment is. Optimizes for output, although with some cost every time something gets posted. Luckily, for most forums, views outnumber posts by hundreds of times. The one issue that system has is that if you're doing a lot of reordering, let's say from quality scores. In that case you'll basically have to remake the thread after every post and after vote that makes a difference. Not recommended...
twism 19y ago
i am in the process of making a news.yc clone... threaded comments are not as easy as it looks on news.yc. [edit] especially when the comments get reordered on votes.
- aston 19y ago
  If you're trying to mimic this forum with a database solution, it's going to be a pain. PG's keeping this stuff in memory, almost certainly as the tree that it is. edit on the edit: scratch that.
  - nostrademons 19y ago
    I mentioned a possible solution here: http://news.ycombinator.com/item?id=33902 http://news.ycombinator.com/item?id=33902, but I'm really commenting because there's a really cool connection between PG's approach of storing it as an in-memory tree and my approach of a 2048-bit index: Y'know how in a typical CS datastructures course you'll have to build a heap, and then reimplement with an array? A heap is conceptually a balanced binary tree where every leaf is filled, while there's nothing tree-like about an array. However, your CS profs were trying to get across that any binary tree can be stored as an array, with the root in position 0, its leaves in positions 1 and 2, their leaves in positions 3, 4, 5, 6, etc. If a node doesn't have a leaf, that position in the array is empty. Normally this is very inefficient - a totally-unbalanced (linked list) binary tree of length 20 would require a 1MB array to hold it. However, heaps are always perfectly balanced, so an array really is the most efficient implementation for them. By restricting users to a certain number of replies to each comment (65,536), I'm effectively constraining an arbitrary tree structure to a 65,536-ary tree. Which can then be represented by an array. If held in memory, it'd be a very sparse and inefficient array. But databases are excellent at storing sparse arrays. If I don't store a potential key, it doesn't take up any space in the DB. And with a good indexing system, I can reference any element in constant time (well, O(logN), but the log base for B-trees is so huge that it might as well be constants). So, I'm really just applying some of the meta-principles of CS coursework to basic data structures. (Actually, I got the idea off a Slashdot posting and had to figure very little of this out on my own, but it's still really cool.) Incidentally, there's apparently a deep connection between number systems and tree structures. You can read more about it in Chris Okasaki's Purely Functional Data Structures. Apparently, every number system corresponds to a data structure. For example, Peano arithmetic = linked lists, binary numbers = binary trees, fibonacci numbers = binomial heaps, etc. There's a short presentation on it here: http://www.informatik.uni-bonn.de/~ralf/talks/BCTCS.pdf http://www.informatik.uni-bonn.de/~ralf/talks/BCTCS.pdf, and I'd strongly recommend the book.

transburgh 19y ago

The one issue I have with the comments are they are not in chronological order and reorganize as new posts are added. It is annoying to figure which messages you have already read and which you have not since they are all mixed together. A simply chronological thread would be nice.

bls 19y ago
On the right hand side of the screen, you can sort the comments chronologically.
- transburgh 19y ago
  Thank you. Never saw that before. That should be incorporated on YC News.

Alex3917 19y ago

On the topic of community makeup, here are some interesting findings that come from Yahoo's social scientists (using Yahoo lists as the dataset): 1) Small groups have higher numbers of core users 2) Private and semi-public groups have higher numbers of core users than public groups 3) People in private groups remain in the core for longer 4) A user who is in the core of one group is more likely to become a member of the core when joining another group 5) New members who eventually become part of the core are more likely to receive messages from other users who have been long-time core users 6) New members who eventually become light users are more likely to receive messages from other light users, if they receive replies at all. This suggests some strategies for building a strong group of core users to transmit social norms. For example, having an idea of who the core users are in other similar communities and making a special effort to reach out to them if they visit your site. Unhappily I lost the original paper and all I have are my notes, so I don't know exactly how they defined the core users offhand.

Jd 19y ago
Alex, this is very interesting. Do you think there might be a way to get one's hands on the original? If there is a person/persons at Yahoo to contact I would do it, as this is something I have thought about quite a bit and would love to see more about the definitions of core, light, new, long-time, large and small. You can email me if you like.
- Alex3917 19y ago
  So I heard this talk at the Cornell Microsoft International Symposium on Self-Organizing Online Communities. The presentation was called "Implications for Future Research; Theory and Methods in Large Scale Analysis of Online Communities." And the three Yahoo presenters were Ravi Kumar, Andrew Tomkins, and Cameron Marlow. Not sure which one those three specifically, but I'm sure you could ask any of them. I've developed this hobby of sneaking into academic conferences. It works best if when everyone else is wearing a suit and tie, you show up in shorts and a t-shirt. That way everyone just assumes that you're friends with one of the speakers, or else that you're Sergei Brin. :-)

naivehs 19y ago

I would like if there is a function to hide and expand the comments. For example one click on a comment will hide itself and all its sub-comments. It is a good way to organize the discussions, and I always believe a website is at its best when scrolling is minimized.

acgourley 19y ago

I have the same problem with reddit and digg: I like to read exceptionally downmodded comments. When comments get modded down so much that they are not displayed, and also they generate a lot of responses, it's the kind of thing I can help but look at. Like a train wreck I suppose. It actually sucks me into the troll MORE when they get such special highlighting. I should say I do like how top level troll posts get put at the bottom for reddit.

deramisan 19y ago
It bugs me that downmodded comments trash karma - political disagreements often get downmodded not because they aren't valid, but because someone disagrees fundamentally. That doesn't seem right.
- icky 19y ago
  Reddit comments DO NOT AFFECT KARMA. Only submitted articles do. I have no idea how you got any different idea into your head, but it was not through observation of reality.
mlgoss 19y ago
You can set the threshold or turn off the hiding of downmodded comments on reddit.

acgourley 19y ago

If anyone is interested in a blog post about the problems with comment and forum systems in general, here is something I wrote on the subject: http://www.digitalkarate.net/?p=20 http://www.digitalkarate.net/?p=20

dantheman 19y ago

I'd like to see 2 modderation options. 1. The standeard up/down arrow -- does this contribute to the debate, is it a troll etc. 2. The agree/disagree poll. This could be a thumbs up/thumbs down.