Several people posted recently in a thread on women, mostly espousing feminist views - only to find that someone had declined to respond to their post, but instead browsed their history and downvoted every single comment or article they had ever posted.

I have two questions:

1. Why would you come to a site like this and pollute the karma system? How does it make you smarter? How does it make anyone else on the site smarter?

2. What would be a good technical workaround? In my mind, some system that detects mass-downvoting and flags a user for review would be preferable, but what should happen then? Should the system be more lenient to higher-karma posters? Who should perform the review process? What should be done with those whom the reviewer ascertains are abusing the karma system? I would prefer some kind of lesson that is more corrective than retributive - it seems to me that people who would perform this behavior are exactly the sort of people who need some of the lessons that this site provides. Any ideas?

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I find it interesting that people do this. I'm going to use this as an opportunity to advocate doing the exact opposite: One thing I've found helps me listen to people more is when I'm having a disagreement with what someone else is saying over the course of a few posts, I go to their user page and find something that looks like it deserves an upvote and give it. This makes me much more willing to accept that the other person isn't being stupid, ignorant or otherwise just generally irrational on the point I disagree with them on.

7Thomas
I seldom answer you. Since almost always when I do, I am down-voted after that. Not that I care much, but enough to not discuss a lot. No matter that you are interesting poster. The karma system is often quite bad.
3mwengler
I agree and wish to chime in that the current system absolutely stops me from stating what I think is reasonable and reasoned disagreement, and even stops me from asking questions. The stackoverflow.com site does NOT have this effect, at least not on me, and I think it is because downvotes cost the downvoter karma there (upvotes are free). So dowvnvotes are reserved for things that are really wrong, best deleted, and a post with a few upvotes will almost always rise to be net upvoted because haters get charged karma to counter upvotes.
3hankx7787
Really? I have a pretty good karma balance and I generally say whatever I want with 0 fucks given about down votes. Maybe you should be less obsessive about it.

It seems to me that the argument "the design is fine because you shouldn't even care about this feature" is wrong.

That a significant number of people seem to think comments like this have some value seems to me to be a bug in typical human reasoning, not a feature.

If the feature exists, it is hard for me to guess how one would not get value from paying attention to the users of the feature in optimizing its design.

5evand
I've multiple times seen the recommendation to use upvotes / downvotes as a method to express a sentiment of "I'd like to see more / less of this kind of post." It seems obvious that the people expressing such an opinion expect the recipients of the votes to care about them. It seems similarly obvious that the developers and admins of the site expect people to care about their karma at least somewhat, otherwise why have it be visible? It also seems like an entirely predictable human reaction to care about what others think of you and your actions, and karma is an expression of that. So, I suspect that you are in a minority in not caring, and I suspect you actually do care at least a little bit. Claiming not to strikes me as more signaling of social status than anything else. I am not at all surprised that it coincides with you having high karma, nor am I surprised that newbies find the karma system more intimidating than people with lots of karma. What did you hope to accomplish with this post? How does adding an insult about the quality of mwengler's posts help that aim? I'm trying to come up with a charitable interpretation of your comment, but I'm not having much luck.
2handoflixue
Actually, the only value I generally derive from visible karma is that I can then sort the comments by karma (which I do). Seeing user karma is only useful if I want to see whether other people also assume they're a troll, and their recent history usually does the job for me just as well... Maybe we should remove, or at least hide, karma, instead of highlighting it? Why do we show user karma and even have a "Top Contributors" list like this...?
1hankx7787
I care about writing a quality post (occasionally). I do not care about the karma, except to the extent that I don't want to have so little that I can't upvote/downvote or post things, but that's generally not a problem.
1[anonymous]
Ah, the old semantic debate between "zero" and "a small number with negligible effects." hankx7787 currently has 164 karma, which is not "high karma" by any stretch of the imagination.
3A1987dM
As for me, I care about the karma scores of each comment of mine (because they show me whether readers think my comments are insightful, out of whack, or neither in particular), but not about my total karma (so that when I'm asked to pay a toll to reply to a heavily downvoted thread, I hit “Proceed anyway” with no hesitation). Likewise, the score of all of my latest twenty comments decreases by 1 in 10 minutes I realize that someone is just being a jerk, and don't sweat it as much as if my net karma decreased by 20 in a several-hour period but with certain comments being downvoted by 2, certain by 1, certain not downvoted, and certain upvoted.
1AlexanderD
This seems to me like the best way to do it. I am sure it has been proposed before that downvoting cost a point of karma; why was this alternative not taken? Technical considerations, perhaps?
2mwengler
Hard to believe it is technical considerations. If you try to comment on a downvoted post (try it here for example) you will get a pop-up asking if you want to pay 5 karma points to comment on a downvoted post or not. So paying karma to do things seems like it is already implemented.
0handoflixue
Huh, neat, they finally implemented that. Thanks for pointing it out :)
2JoshuaZ
Hmm, interesting. Has it been on specific issues or across a broad variety of subjects?
-6Thomas

Because LW is a multiplayer video game where you are winning when your team is getting more karma relative to the enemy player team. Whenever a video game is misdesigned to allow uninteresting grinding to contribute to winning, some people will do lots of uninteresting grinding to win.

An alternative would be to recognize that an upvote and a downvote are more orthogonal than opposite. A post or comment with 20 upvotes and 30 downvotes is clearly a very different post than one with 0 upvotes and 10 downvotes. A user with 2000 upvotes and 1500 downvotes is clearly a very different user than a user with 25 upvotes and 500 downvotes. If lesswrong simply reported upvote and downvote tallys side by side rather than netting them, a lot more information about posts, comments, and users would be available to readers. The current system is incapable of distinguishing between morons, trolls, intelligent newbies, and valuable and intelligent gadflies. Reporting positive and negative votes separately would help a lot.

[-][anonymous]170

This has only been a feature request since the forum started.

6falenas108
This suggestion usually gets a lot of support, is there a reason why it hasn't been implemented?
1[anonymous]
Time, resources, and programmer-hours: how much more is SI supposed to spend on incidental forum problems?
[-]gwern100

Technically, I think this is more Trike's problem, so it would be more like 'how much more of Trike's time is this supposed to take up or be diverted from other LW maintenance/improvements?'

3EricHerboso
Several months ago, another user offered to set up a fork of the reddit enhancement suite that could achieve this and other features for users interested in them, but the project never took off. Arguably, this is a poor way of solving the problem, because it requires opting in, and most users would continue to see the old look instead. But it would be better, perhaps, than doing nothing.
4A1987dM
Seriously, how long would it take? Unless the number of upvotes and the number of downvotes are not stored separately in the first place (which I don't think it's the case -- aren't the “Best”, “Popular” and “Controversial” sorting criteria based on them?), I wouldn't expect that to take more than 0.1 programmer-hours.
8mwengler
I was upvoting for the idea, but then retracted at the suggestion that ANYTHING real takes less than 0.2 programmer-hours.
5faul_sname
Several real modifications to the code base I work on have taken less than 0.05 programmer-hours. About half of which was booting up and connecting to the server. In this case, it would be a matter of changing something along the lines of this: <span class="votes " id="score_<? echo $comment["ID"] ; ?>"> <? echo $comment["up"] - $comment["down"] ?> point<? echo $comment["up"] - $comment["down"] != 1 ? 's' : ''; ?> </span> and tacking something along the lines of this to the end: ( <span class="votes " id="score_up_<? echo $comment["ID"] ; ?>"> <? echo $comment["up"] ?> </span> | <span class="votes " id="score_down_<? echo $comment["ID"] ; ?>"> <? echo $comment["down"] ?> </span> ) I don't know the exact implementation details server-side on this, as I don't have access to the LW source code, but it really would be a minor tweak (unless upvotes and downvotes are counted together, in which case it would be nontrivial).
4ChristianKl
You are talking about code on which you work. That means that you already invested a lot of time into knowing the code base. If SI search someone to implement this they probably need to spend some time to understand the code base before they can make changes. The source code is open source.
1mwengler
They HAVE implemented a feature that pops up a question "Replies to downvoted comments are discouraged. Pay 5 Karma points to proceed anyway?" and then you choose whether to spend 5 karma points or not to reply to the downvoted comment. It doesn't seem to me the feature to report positives and negatives separately would be less coding than this one they have put in place. See http://lesswrong.com/lw/fnk/meta_retributive_downvoting_why/7wls?context=3 for a comment you can see the pop-up question at when you try to reply.
3[anonymous]
I don't understand the logic here. It sounds like you're saying something like: "A friend loaned me five bucks, so surely he can loan me five more." By induction, the friend has infinite amounts of money.
6mwengler
No, it is something like "A friend went to a movie 12 times in the last 15 weeks for $5 each. So if I find a movie the friend will like and it is $5, he'll probably want to go."
6dbaupp
There's even an issue for it.
2ArisKatsaris
It would give information, but would that information be beneficial though? Right now people moan and complain if they ever see their comment be at -1. Afterwards people will be moaning and complaining if they see a single downvote, even if the net score is a positive.

I want to point out that it is possible that some of these downvotes* could be honest assessments of a comment history. If a user notices you by reading one comment, that user might become interested in other comments you've written, and if this person didn't like one comment, he may also dislike other comments in which you express similar ideas.

* Which were not from me, because i have not read the conversation you linked to.

I say this because i realize that i have (arguably) done it before. I noticed a comment from one particular user which deserved to be downvoted. Then i read all the related conversations and downvoted the other comments in which that user repeated more or less the same thing. Then, i began reading earlier conversations in which that user had participated, and found that many of this user's comments were bad for similar reasons, but i did upvote about 10% of them that were good.

Overall, the user who had been downvoted saw a sudden karma drop within several minutes; they specifically made an accusation of retributive downvoting.

Long story short: on at least one occasion, a user who complained about mass downvoting was actually experiencing a rapid series of honest downvotes.

I would argue that when you do this, you owe it to the person you are downvoting to explain WHY you believe they are systematically wrong. A series of downvotes + one helpful comment is far preferable to a simple series of downvotes, even if it costs you karma to do so. As an example:

my response to an apparent troll comment on Brain Preservation

See, just smacking someone without telling them WHY you're smacking them leaves them to all sorts of conjecture as to what happened - if whomever had downvoted 30+ of my posts had left a single comment explaining why, I could have learned from it. As it is, I have no evidence to distinguish retribution from legitimate correction, and no data with which to correct myself even if it IS an attempt at legitimate correction.

Actually, thinking on this further, a series of downvotes plus an immediate comment explaining why is EXACTLY the right behavior - the sudden plunge in karma will get the user's attention, which they can then direct to the reply - the combination of mild social shaming, "score penalizing" and corrective explanation is a quite powerful way to drive home a lesson.

1thomblake
I do this regularly. Finding comments worthy of downvotes is a (necessary) chore, but user histories are low-hanging fruit.
1TimS
Nonetheless, it would be a courtesy to send some written message if there is a common reason for the downvotes - at least for established user. If you've talked about more than one topic - like monkeymind didn't - it's hard to know from downvotes of old posts what someone wants less of.
4MinibearRex
I think any message of this sort is likely to lead to some unpleasantness. "Hey, I just downvoted a whole bunch of your old posts, but it's ok because I actually did think that all of those posts were bad." Downvote things that deserve to get downvoted, but don't make a scene out of it that's just going to poison the discussion.

Someone spending their precious time going through someone's history to decrease their near-meaningless number as much as they possibly can is already losing. I hear about this happening so infrequently, and it's so totally inconsequential, that I don't think it merits thinking up/making changes to anything.

All protestations to the opposite aside, I very much doubt that karma is generally viewed as "near-meaningless". It is the main avenue of feedback and affirmation in what is often viewed as a rather intimidating environment (by newcomers especially).

As for those spending time with retributive downvoting, how do you know that they do not gain more satisfaction out of that than, say, watching the new BSG webisodes, using their "precious time". From Will_Newsome to Wei_Dai, I've seen even some veterans explain the importance they ascribe to karma. Would you laugh it off if your karma score were reduced to 0 by one guy with a few sockpuppets?

It's the only quantifiable metric in this social game. There even is a "top contributers" meta game on the sidebar. Of course all that makes it en vogue to pretend not to care, similar to wealthy people acting as if money weren't worth talking about.

If you truly don't care, good for you.

On individual comments and posts, the karma system is valuable for telling you if you're being stupid or not, and I appreciate it for that. The total karma score is (how long you've been on LW) (how often you post) (how much people like what you say); it says something like "how much you contribute to this site", which I find much less interesting, and I personally don't care if it's accurate.

I am, in fact, accusing people who downvote all posts by one person as using their time incorrectly; there are so many other things they could be doing that would make them happier and better-off, including nothing at all, that there's not much excuse for going through with it.

If my karma were reduced to zero, I would continue carrying on as I do now, commenting on this and that, and my karma would from then on be a positive number I don't pay attention to. A phlegmatic disposition has its advantages.

9ialdabaoth
The problem is that it isn't meaningless. I was in the middle of a rather interesting ethical discussion, and many of my posts that I had just made went from 0 to -1, potentially dropping off of the radar of other readers. All it takes is two users colluding (or one user with an additional sock account) to effectively shut down someone else's entire voice. If a post goes from 4 to 3, that isn't a big deal, but if it drops below the minimum display threshold before anyone gets a chance to read it, the entire flow of conversation gets disrupted.
-6Kingoftheinternet
3JoshuaZ
The problem is that once you give humans a number they have some control over they will try to modify it and care about it. Even if they only care a little bit. This is to a large extent how MMOs work for example. Prior discussion of this issue on Less Wrong which I can't find at the moment resulted in the Kill Everyone Project being pointed out as an extreme real life example. And since for karma one only has partial control, this essentially amounts to randomized reinforcement, which is one of the most addictive forms of reinforcement.
[-][anonymous]100

I've been retributively downvoted by one or two people over the past week and have lost about 110 karma. (Though I don't think I posted in the thread linked by the OP.) I agree that we need a system in place to correct and/or prevent abuses of the karma system.

At bare minimum, I think that LW should have a private log of users' up-vote/down-vote history accessible by the moderators. If someone complains of karma-assassination or the like, moderators could review the log and take appropriate action.

3mwengler
I'd support having such a log for administrators, although I find it likely there already exists such a thing as LW does keep track of every upvote and downvote of every user on every post/comment they up/downvote. I would only want them to take "appropriate action" if appropriate means announcing clearly any new policy and preferably automating that policy. I do not think an unannounced one off "you are a bad person because you downvoted whoever 7 times thursday so we are X'ing you" without putting some automation and/or warning in place is appropriate.
-1ialdabaoth
Well, the best I feel comfortable doing is read through all your posts (which seem pretty reasonable, btw) and upvote everything that's at 0 or lower, unless it's particularly egregious (so far nothing is). One thing that this whole process is teaching me is an appreciation for some of the arguments made here ("karma isn't that important on the whole"), but in the case of a good post not being read because it's too low-karma, I think karma is seriously important and deserves further attention.
0[anonymous]
Thank you very much for taking the time to do that! I promise to do likewise once time permits. I should log off LW for now in order to get some work done...

If I may make a suggestion, please pick a different user to perform that task on, rather than me. I would prefer to not have my karma distorted by primate pack-alliance instincts, for or against, and another user already performed corrective action against the original punitive action. Of course, if anyone comes across one of my posts and considers it worth upvoting, please do so - I just want to avoid systematic upvotes for exactly the same reason that I want to avoid systematic downvotes.

2[anonymous]
Oh, I was under the impression that you, too, had been systematically down-voted. My mistake. I will refrain from doing so. Edit: My reading comprehension skills must be on vacation tonight.
6ialdabaoth
I had, but someone else already re-upvoted, so further reaction risks overcorrection.

I think flagging for moderator attention is far superior to any automated response. I really like JoshuaZ's opposite approach, and I have no problem with someone repeatedly encountering a troll, and then going back and downvoting other trolling comments selectively. What I have a problem with is retributive downvoting without regard to the content of the comments being downvoted.

I'd be pretty happy to leave appropriate responses to moderator discussion. My suggestion would be something along the lines of undoing all downvotes that person made within the re... (read more)

3[anonymous]
How do you deal with the induced increase in censorship-trolling noise? With political differences among moderators? With increased moderator fatigue? No, the correct solution space is the realm of automated applied psychology.
1evand
I'm not sure what you mean by this. I'm hoping that this is a relatively rare occurrence. I'm also hoping that the moderators have handled political differences before, and I don't see this as more likely to cause political conflict than other moderator actions. That's part of why I proposed undoing all recent downvotes, not a selected set. Undoing only some seems like too much work, and also too much discretion. I'd love to see data on downvote patterns; if the problem is far more common than I think it is, I'd be inclined to agree with you. Maybe, but I don't find that to be obvious. I worry that any system with a threshold (too many downvotes triggers an automated response, or something similar) is likely to produce weird distorted incentives. Charging karma for downvotes doesn't have this problem, but I'm not sure whether I like it or not for other reasons (likely to discourage retribution less than it discourages normal downvoting, see Kindly's comment). I'd rather look at individual proposals from both solution spaces before concluding that one is the correct space.

It is also very interesting to notice that the subject is charged enough to provoke this kind of behaviour. I don't think it has ever happened on a discussion about a technical fine point of some decision theory.

This evidence increase the probability I have on the hypothesis: "LW crowd has totally failed in raising his own sanity waterline, on average. There are people who undoubtably increased their own, but they are more than compensated by people who get even more irrational on a rationality forum."

8evand
Do you have evidence that favors that hypothesis relative to "The general improvement in the sanity waterline at LW is sufficiently small and poorly distributed as to make no difference among a large fraction of users when it comes to emotionally charged topics, even though both the mean and median user has raised their sanity level."?
-2MrMind
No, I don't have enough data to discern between the two, but I think in measuring the rationality level I am/was assigning a higher weight to the charged topic like relationship between member of the opposite sex and the image LW projects against mainstream communities.
[-][anonymous]40

Should have been a comment in the Open Thread.

[-]TimS170

Given the volume of responsive comments, I'm not sure why you think this is true.

I think it could certainly be wise to implement a limit on the rate at which one can downvote posts by a specific user, or, if that's technically difficult to implement, the rate at which one can downvote fullstop.

The more involved measures you suggest would require effort, but I suppose the question becomes: what is LessWrong for? If it's actively for improving rationality, such measures could be worthwhile, assuming we could find or reroute some moderators / mentors / monitors.

[-]Dias30

Not that I've ever bothered to do this, but you're not being very charitable. Maybe they just looked over someones entire comment history and decided that they'd like less of everything that person said. It doesn't seem abusive to repeatedly downvote clear trolls. Obviously, some people may disagree as to who the trolls are, but that doesn't mean you shouldn't punish those you think are.

4ialdabaoth
In which case, a single comment reply to the user, explaining WHY they would like less of everything they said, would be preferable in addition to the downvoting. That way, the downvotee knows what they did wrong and what they might do to correct it.
2Eugine_Nier
Well, EY has been giving increasingly unsubtle hints that he doesn't want people relpying to comments they consider downvote worthy.

As to 1: I have no idea whatsoever, but we clearly have a proof of existence. As to 2: this seems like the problem of strategic voting. We want people to up and down vote in a manner that reflects their true opinion of the comment, but the karma aggregation system incentivises voting in a manner that reflects the maximum exaggeration of their opinion of the poster.

I realized a generalization from recording up and down vote total separately is to have a few categories of vote. Perhaps a post could be voted "up" "down" "agree" "disagree" "troll". In a system like this, it would be troll votes rising above a relatively low threshold that would grey-out or hide posts and comments.

I think this is somewhat clunky compared to just reporting up and down separately. But I wanted to throw the idea out there for those who wish to think about this question.

9falenas108
In addition to the clunkiness, it also sends the signal to outsiders that trolls are a big problem on this site, which they aren't.
[-][anonymous]10

I recently had a 30 point karma hit.

[This comment is no longer endorsed by its author]Reply
[-][anonymous]00

I have an idea I want to run past everyone. It occurs to me that you could just team up with any other poster at all to ask for a karma infusion.

For instance, let's say you just received a bunch of 20 retributive downvotes on comments, and you teamed up with me.

You could message me and say "Michaelos, I just received a bunch of retributive downvotes on my last 20 posts. Could you give me a 20 point karma infusion?" And then I come by and upvote 20 of your posts, and your karma is back to where it was.

Also, if I want to be helpful on more than jus... (read more)

[This comment is no longer endorsed by its author]Reply

You could message me and say "Michaelos, I just received a bunch of retributive downvotes on my last 20 posts. Could you give me a 20 point karma infusion?" And then I come by and upvote 20 of your posts, and your karma is back to where it was.

Sounds easier to just google for an inspirational quote to pass of as a rationalist quote in the quote thread.

3ialdabaoth
I'm replying to this even though it was retracted, because it's an idea that I think needs to be discussed and I appreciate that you brought it up. That said, I'm deeply skeptical that such a system would lead to less abuse, rather than more. I feel that karma systems should accurately convey information that is useful to the users, so I tend to be pretty touchy when I sense that they're being abused. Statements like "they're just meaningless numbers" indicates, to me, that a karma system is not performing its job correctly. Ideally, karma should convey several pieces of information, both to the audience and to the speaker: 1. How the audience feels about the speaker's specific comment (this is the most important) 2. Why the audience feels that way about the speaker's specific comment (this is almost as important as 1) 3. How the audience feels about the speaker in general (this is the most problematic piece of information, because all of the primate pack dynamic instincts come rushing in) 4. What the speaker should work on to improve themselves (this is very difficult to convey, because all the problems that cause 3 to fail are amplified when applied to 4).
0[anonymous]
I retracted it primarily because I read more of the thread and realized that the idea was too similar to another discussion which had already been brought up, which made the initial comment out of place and other parts repetitive. At that point, I was left with a "Since this has been brought up before, rather than posting it as a new idea, let me just retract it and upvote the other person who suggested it." But that being said, I'm not sure I fully understand your abuse concerns. If someone wanted to abuse the system, they can just sockpuppet up their karma without any other people. Using this method is substantially less prone to abuse since there is another person involved, and it seems to parallel things which would not be considered abusive. If you are asking for too much positive karma, presumably the other person would say so. (It does cost them a small amount of time/effort to karma repair you, after all.) However, I suppose if you wanted to be completely sure you were not abusing the system, you could just ask your friend "Could you read all of my recent posts and let me know your thoughts?" If your friend saw "Wait, these are all at -1, but they're all perfectly fine." they would probably systematically upvote you even if you didn't actually ask for upvotes. Asking for a friend to look at your work by itself does not seem like it could be considered abusive under any reasonable set of rules. What do you think of that alternative?
5ialdabaoth
It seems better, but does seem to lead to a risk of echo-chamber situations. Being human is hard.
0[anonymous]
You could always ask for two entirely separate friends to BOTH review your work and have them not know who the other friend is (or for that matter, even that there WAS another friend reviewing your work, if needed.) They wouldn't be able to easily form an echo chamber because they would not be in communication with each other. Alternatively, you could, if you really wanted to avoid an echo chamber, explicitly ask Poster A "Can you review this with the intent of finding flaws? Crocker's rules apply, be as harsh as you like." and Poster B "Can you review this with the intent of finding good points?" It does not seem like that approach could form anything remotely like what I would consider an echo chamber.
2TimS
That's asking a fair amount from people I only know over the Internet. I could count on one hand the number of people that I expect a >50% chance of response (even refusal) if I asked them for this kind of help on this site. And I'm not sure anything is wrong with that.
0[anonymous]
I, or another person, would appear to be volunteering reading and offering relatively unskilled commentary on short blurbs of rationality related text. I know I personally already do that for fun when I post here, I just somewhat randomly select which items to reply to. This would essentially be what I would already be doing except people would be sending me what to read, so it doesn't seem to be a lot of work for me at all, unless the response was unexpectedly massive. I guess what I am considering is like Jsalvatier's help desk at http://lesswrong.com/lw/eto/lesswrong_help_desk_free_paper_downloads_and_more/ but at a lower level for people who have simple questions like "Why was this downvoted?" Can you go into more detail?
0mwengler
And of course you can just retract all your posts to avoid having them downvoted. They are still readable through the cross-out lines. And people can still respond to them with comments. A nice back-door way to opt out of the karma system?
0atorm
I see what you did there.

Perhaps detecting a large number of downvotes to the same user? Just spitballing here.

I think the system on stackoverflow.com works well. There, making a downvote on somelne else costs you something in your vote total, whereas upvotes are free. The result is that genuinely wrong answers get a few net downvotes, presumably from very high karma individuals who don't mind the expense, and who also are presumably a good choice for "arbiter" type roles given their very high karma. stackoverflow.com karma system is pretty detailed, with priveleges and permissions coming at higher and higher personal karma levels, but I would say "charging" for downvotes is the most relevant feature for the most improvement here on lesswrong.com.

8Kindly
Currently there is (as far as I know) a downvoting limit of 4x your total karma, which seems to serve the same purpose. It's possible, of course, that this limit needs to be lower. But if, say, the limit were half your total karma, then it wouldn't change much to additionally charge karma for downvotes: all karma would remain the same to within a factor of 2. Of course, charging karma for downvotes would probably also discourage downvoting, because people don't like their numbers going down. I'm not sure if this is a good thing, though; incentives mainly work well for people who are already using the system as intended, so this would discourage legitimate downvoting while leaving retributive downvoting alone.
[+]ewang-60
[+]Shmi-190