Ask HN: Do social sites with karma need a decay function?

[abstractbill]

If karma in a social site is a reward for good behavior, it seems like it always becomes harder and harder for new users to "get ahead" compared to those who have been around forever. Perhaps this lessens the incentive to good behavior over time?

Do such sites need to implement some kind of "karma decay" system, to prevent the leader-board from becoming more static over time and encourage new users to behave themselves?

[Xichekolas]

No.

I have been here since fairly close to the beginning (for the public anyway), and have moved around in the rankings quite a bit. Since I quit my job in May, I have sunk from 64 to 100. (I don't spend several hours every morning reading HN with my coffee, since I'm rarely up in the mornings now. ;) I can assure you that newer people are able to push ahead of older people if the older people stop participating.

For instance, I have been on here five times as long as qhoxie, but he has three times the karma I do. The reason the leaderboard might look stagnant is that the people in the top 10 are there for a reason... they are consistently more productive (in the karma sense) over the long run. If they started resting on their laurels, people like qhoxie would rapidly overtake them.

Also, as the site grows, it gets much easier to rack up tons of karma. At one time a story was really hot if it had 20 votes. Nowdays it's common to see things go well over 100. I was once really surprised to get 26 karma for a comment I made. Nowdays there are gems on here that regularly go over 50. More people voting means the new users actually can catch up faster.

(Of course, this also assumes that karma actually matters, which I debate. It's nice to know people appreciate what you said/posted, but you shouldn't just be saying/posting it to win a karma video game.)

[unalone]

I agree. As people join, karma becomes easier to get. The longer I've been on here, the faster I've gained karma. New users with a lot to say will rise quickly.

And the karma shouldn't be such a big deal! When I see somebody with low karma, I assume it's because they've been less active. The trend is always that the more you post the higher you'll get karma, because high-rated things have more visibility and therefore are more likely to get voted higher, and because fewer users can downvote. Karma's really fun, but people get way too worked up over these rankings.

[run4yourlives]

To be honest, I think the up/down notion of karma is the problem.

I'd prefer to see words being attached to comments instead of numbers. "Funny", "Insightful", "Accurate", and their opposites could be the method of rating, with "leader boards" showing the funniest, most insightful etc.

The notion of me as a user being "worth" #### points would vanish, and it would be replaced with a general "run4yourlives: slightly funny, not often accurate" descriptor based on the ratings of my peers.

Slashdot tried this, but they kept linking it back to numbers, which I think is where it failed. The idea should be to remove the notion of a numerical worth altogether.

[abstractbill]

I like this idea a lot.

[WarTheatre]

This is only a problem if there are very strong mechanisms in place that encourage/force people to actively compete for karma so that they don't risk losing their status. For instance, if high karma people are given more exposure or special benefits (early access to content; free stuff, etc.), you can bet this will lead to an increase in active karma manipulation. People will simply act accordingly to get better karma, which might not always be preferably depending on the type of community you run.

Karma is very important to people online and fooling around with it can cause hurt feelings. After all, Karma is often the only explicit reward that community members receive and is a way of being recognized for being a productive, helpful, nice and ultimately good member.

Regards, WarTheatr

[MoeDrippins]

What he said. If there was some benefit to having more karma than "the other guy", then maybe.

That said, I'd still be in favor of one, only because "news" is temporal so "old" karma shouldn't be worth as much as recent. But, I'm shooting from the hip here and there are probably unintended side-effects I'm probably not seeing.

[PieSquared]

I think a good idea would be to treat karma the same way that tennis rankings are counted: Only the past 52 weeks are counted. So if you gain 1000 karma in a year, then don't participate, your karma will be 0.

That will encourage continual good behavior.

[mechanical_fish]

I think rankings in other sports might be more fun if they worked more like HN rankings. Baseball fans do a lot of that. It's kind of what baseball statistics are all about: The player in front of you is not just competing with himself, and the other players on the field, and the other players in the league. In a sense, he's competing with Lou Gehrig.

Of course, the reason to avoid putting dead players in the rankings is that the people who prefer watching competitions between living players -- i.e. the majority of fans -- don't want the dead ones cluttering up their leaderboard. But this is the web, not TV, so the solution is simple: Multiple leaderboards. Create a version of the HN leaderboard that only counts the past 52 weeks. Put it up at some URL or other. Then people can decide to use the alternative leaderboard if they want.

Heck, if we want, we can allow every reader to create his or her own leaderboard algorithm. Then we can have big chair-throwing debates about which leaderboard best represents the True State of Play on HN. That is exactly how the world of baseball statistics works. ;)

[Prrometheus]

You assume that karma encourages good behavior. If that were the case, then I think this would be a good idea.

[run4yourlives]

Karma ensures popular behaviour, not "good".

If that's what you're gunning for, it's a great idea. What's popular is only dependent on your users and their tastes, and this can change over time.

[sh1mmer]

That encourages lock-in. What if my wife had a baby and I went offline for a year because I didn't have time. Would that make my opinions suddenly invalid?

Tennis rankings are based on physical form. Physical form is something much more likely to change year to year than intellectual form.

Someone might be out of date with the latest topics, consensus from the community, etc but it doesn't imply their thinking apparatus or world view has dramatically altered.

[iamelgringo]

I don't think that the karma decay function would work or be helpful. Most people on the leader board, got there from hard work and dedication to make this site a really cool place.

I know that my participation in this board was a deliberate exercise in community building. I worked my tail off in trying to find interesting material that my fellow hackers would enjoy reading. It's pretty common for me to spend 20-40 minutes crafting a response to a comment.

A number of us were upset at the downfall of Reddit, and we were determined to make this a better place. I was one of those. And, while I still use a highly curated form of Reddit for news. I never participate in discussion there.

So the leader' karma scores reflect how much we've invested in this site. I don't think that's a bad thing. People on the leader board have made this site what it is. And, they're still the backbone of the site. Can you imagine what it would be like if nickb or edw519 stopped submitting? It would dramatically change the tone of the site, since their contributions to it are so substantial.

I know that I haven't been as active the past few months, but that's because school's done for now, and I've been building product. With any luck, I'll be launching by January. We'll see.

But adding a decay function to a site like this would only punish people who have contributed lots.

Maybe a better answer would be to increase the size of the leader board to the top 200-300 karma. That would give some recognition to the people that are putting in more work on the site, gut their karma isn't on the top 100. Just a thought.

[mariorz]

> Most people on the leader board, got there from hard work and dedication to make this site a really cool place.

Try posting every tc, mashable or rww article you come across for say a week. I predict your karma will go way up and this site will be less interesting because of it.

[mechanical_fish]

Given that I have fairly high karma, it's hard for me to claim that I'm unbiased...

... but this is a bad idea. For one thing, decaying karma is devalued karma. Why should people work so hard to gain something that is crumbling into dust all around us?

But the bigger problem is that absolute value of karma is not that important. The important social signal is in the first derivative. If you make a post that people like, your karma goes up. If your flaming instinct gets out of control, your karma stays constant or goes down. If karma is constantly going down anyway it will confuse the issue. Either you're going to have to do some complicated mental arithmetic to figure out whether or not you suck ("let's see, I don't think I've looked at my karma total since Tuesday, so my karma should have fallen by 10 by now, but OMG I think it's fallen by 14, so I must suck!")... or, more likely, everyone on the site will subconsciously interpret the ever-falling number as a sign that they suck 100% of the time, so everyone will feel like crap at all times.

[jbert]

> Why should people work so hard to gain something that is crumbling into dust all around us?

Like money which will decay with inflation, or perhaps the regard of people who will be dust in a few decades?

> If karma is constantly going down anyway it will confuse the issue

If that's a problem, the site can provide the 1st derivative (ignoring decay). A bit like music charts ("at number 10, up 5, it's...").

Some sites (perlmonks) already give you an xp (karma) delta whenever you reload the page. A last 24-hours delta would be more useful (again ignoring decay).

Then again, I don't see what the utility of decaying karma is personally. It smacks of "what have you done for me lately". I think it's OK to respect people for past glories.

[epoweripi]

I'm just thinking out loud.

Elders a.k.a old people in a normal society are respected because they have been in the 'system' longer, irrespective of their accomplishments. That to me is one form of karma (Age)

Also, ppl who have accomplished a lot irrespective of age are looked up as role models in the society : the form of karma that most social sites capture - contribution.

Similarly bad acts reduce one's karma - independent of the good he has done - Hans Reiser comes to mind.

The total karma could be a function of (age, +ve contribution, -ves). The age can be based on some condition like page views/logins done etc. - passive contribution OR can be unconditional too (today - creation date).

Active contributions can be also be classified into major and minor. Say a particular post generated > 1000+ points. It has to be given importance irrespective of age. Smaller events can be dampened - just like in the real world - no big deal. Same goes for -ves too. murder != pickpocket.

my view, karma = function (age, major +ve, minor +ve, major -ve, minor -ve)

and only the minors need to be decayed.

[axod]

One thing I've thought about in the past is should an upvote/downvote result in a percentage gain/loss instead of absolute.

The thing is, if you've only got 3 karma, and someone downvotes you, that's a big deal. But if you've got 3000 karma and someone downvotes you, it's not. Maybe a vote should result in a 1% gain/loss.

On the other hand, it probably doesn't matter that much :)

[walterk]

I would just hide (not remove) karma entirely. Submissions, comments, and users. That removes the incentive to game for karma and mitigates against the bandwagon effect, while the karma system still determines placement of submissions and comments within their respective threads. And I'd argue that high placement is reward enough in itself to promote meaningful contributions. Obviously, people can still try to game for placement, but it's less interesting when it doesn't contribute to an overall user score.

Anything having to do with a leader board, in contrast, simply encourages people to game for karma.

[pg]

Not if they're growing.

[mseebach]

It would seem that the Slashdot system of capping karma at "Excellent" is s means to this end, but Slashdot isn't a better place for it.

I'd say, that if anything, down-voting should count proportionally to your karma. If you've got 5k karma, you could go on a flaming-spree for days, and still have more karma than the best newcomers.

That said, I don't think it's that big of a problem. When I (and it's seldom) look at a users karma, I always look at it in relation to created-days-ago. Karma 100, created one month ago > karma 200 created a year ago.

[grag]

While you can probably improve a karma system with decay or a more complicated algorithm, there's something to be said for having a system simple that your users understand. I'd make a wild guess that karma wouldn't be as interesting to users if they can't figure out how their actions directly affect their score.

[bayareaguy]

The answer depends on what problem you think the karma-delay function is intended to solve and whether or not there is evidence that this problem is real.

I think the only place a decay function makes sense is in providing historic views of the leaderboard.

[vaksel]

well reddit haa a daily/weekly top 10 growers list on top of all time http://www.reddit.com/stats/

[Shamiq]

I don't participate for the karma points. It's more of a measure how much non-conformists agree with me. Which sounds kind of ironic, doesn't it?

[lpgauth]

A better option would be giving/removing non constant karma point (not always 1).

So something like +- 1/(1 + karma/2500).

[dmaclay]

YES