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Hi Alf,

Tactic rating calculation seems has bug, I loaded a database of tactic, when I solve first tactic it increases rating by 45 but when I solve thr bext puzzle it reduce the rating few points...

Thanks for your help
Navid

Navid,

Thanks for your message.

I have taken a look at this today and released a new version (1.0.98)

That said, I have not been able to reproduce the problem where you lose rating points if you solve a puzzle. That seems very strange.

This is how the rated tactics for logged on users works:

* I'm using a K factor of 30, i.e. max available points to lose or gain is 30.
* In the first 8 games, you gain and lose double rating points(sort of a provisional state)
* It's hard to automatically determine the elo of a puzzle. This is the formula I have used so far

elo = 1000 + (moves in puzzle * 250) - (seconds used to solve puzzle * 4).

A five move puzzle will give you an elo of 2250. If you spend 1 minute(60 seconds) to solve it, the measured opponent elo will be 2250-240, i.e. 2010.

In the update today, I have made some changes to how many points you lose if you fail to solve a puzzle. Let's say it's a five move puzzle and you solve 4 of the 5 moves. In this case, you loose only 20% of the points since you solved 80% of the puzzle.

I have also implemented a hint button today. Clicking this button will play the solution for you and you will some elo points(50% of normal).

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Alf

Thanks Alf,

I have suggested how to claculate rating, I think that would be one of the best way possible.
Defining rating for each tactical database & then using Elo formula for calculating. In fact we make a scenario if a player can beat an opponent (here the opponent is Tactical puzzle). https://en.wikipedia.org/wiki/Elo_rating_system

Thanks
Navid