# What is the rationale behind that the flag score increase is non-linear after reaching 500? [closed]

I am just confused with the flag score?

Why the flag score increase is non-linear after 500? I know there is a max cap score of 750.

Why don't just make it as linear and increase the max cap, say 2000?

• 500 was originally the cap, I can't recall why it was then changed but there's probably a meta post for it somewhere. It does, however, mean that the "high flaggers" have separate scores and so can be still be sorted. Aug 9, 2011 at 13:03
• @DMA57361: I can't find the question, so i post it out ;p Aug 9, 2011 at 13:04
• @DMA57361: I saw someone got 750, and that should be the max Aug 9, 2011 at 13:05
• 750 takes a hell of a lot of flags to reach Aug 9, 2011 at 13:07
• – user162697
Aug 9, 2011 at 13:07
• @Siva: it is not really the same question what I am asking for. I just am curious on the non-linear increase rather that linear increase Aug 9, 2011 at 13:09
• @Kit Ho: Yes, I am aware of that. I didn't use the word duplicate. I have only mentioned related.
– user162697
Aug 9, 2011 at 13:10
• @DMA57361 meta.stackexchange.com/questions/97890/… covers how many flags it takes to reach 750 Aug 9, 2011 at 13:21
• possible duplicate of Unnecessary precision displayed for flag weight Aug 9, 2011 at 13:26

Lets start by looking at a graph of the flag weight for 6 imaginary individuals flagging 400 times at various success rates.

(because I don't know the actual algorithm used, I'm going to assume each successful post-flag above 500 will increase the flag weight by `10 * (750-weight) / 250`. That should be close enough for our purposes.)

As you can see, anyone with a success rate over 50% will eventually reach 500. Once our imaginary people pass 500, their flag weight starts to plateau at various levels depending on their success rates. If the cost-reward was symmetric then we everyone over 51% would eventually meet up again at the top.

Not only does this allow the system to distinguish between a "good" flagger and a "bad" flagger, but also between a "good" flagger and a "long term ok" flagger.

For simplicity, the graph assumes that people flag consistently with their good and bad flags evenly distributed. In reality, there will be some local variations and some people will change their ways (for better or worse). I found that the flag weight continues to (roughly) track the same path even with small local variations, but a sustained change will cause the flag weight to find a new plateau.

Update As per Hendrik's recommendation, I revisited this using `10 * Pow(10, -(weight-500) * 0.008)` which is reported to be the actual formula used.

The overall result is mostly the same but with more differentiation in the upper regions.

Although its not shown in this graph, the 99% user will still hit the 750 cap in a little under 800 flags past the end of the graph, whereas the 98% user will not reach 716.3. However, I'm not sure such specific details are particularly meaningful in the real world ... except perhaps to determine the minimum number of consecutive successes required between each failure to guarantee some sort of "forward motion" (probably just short of 99).

• It was around 780 flags to get to 750, with a pretty good accuracy (~1% declined), a lot of it depends on when you had the flag declined. Jan 20, 2012 at 18:25

The idea is that this way your flag weight will always approach a certain number depending on the current success rate of your flagging.

If you're 50% successful, your weight will approach 500. If you've been 100% successful lately it will approach 750. For any rate in between it will asymptotically approach a number between 500 and 750. If your recent success rate changes, it will start adjusting towards the number for your new success rate.

Brian's answer here has some great graphs that explain the concept really well. Have a look at it.

• So this scoring system is to distinguish who is the "real" good flagger? Aug 9, 2011 at 13:27
• @Kit Ho: The idea is that the flags get sorted by the flag weight of the person who made them. So the higher your flag weight, the more likely it is that your flags will be handled quickly as they will be near the top of the list. Aug 9, 2011 at 13:30

Speculations about the formula are in What's the flag weight formula in the 500-750 range?. The rationale is basically "with greater power comes greater responsibility." Once you're established as a good flagger, another good flag doesn't provide much more information about how good a flagger you are.