EFFICIENCY is your quality score relative to other players in the War Thunder game. An average player has 50% EFFICIENCY, top one has 100%. Its calculation is slightly different for each mode. If, for instance, your efficiency is 65%, this means that you play 15% better than an average player, but it does not mean that 35% of players play better than you.
Sure. Now EFFICIENCY is being calculated based on win rate and frags per battle. We make polynomial interpolation of each feature by the method of least squares, then add their images with some coefficients, and then make polynomial interpolation by the least squares again.
At this point in the arcade mode winrate is more important, and for the realistic and simulator modes frags per batter have more effect. But this difference isn't very big, so these characteristics can be considered of equal importance.
EFFICIENCY is dynamic characteristic, which depends not only on your records, but also on the average level of players. Due to adding new players to the database (which occurs daily) average values change, and so does your efficiency, even if you haven't played. It is also worth noting that due to the Snapshot bug average values can vary quite a bit.
Some characteristic of a player can be shown incorrectly in the official website's statistics. Because Thunderskill uses official War Thunder statistics, this bug can make features such as Frags per battle, Kill Death ratio, and Average lifespan to have either very small value or even zero. At the same time, real values will be much bigger. The bug frequently occurs after game updates and affects large number of players, which makes strong fluctuations of average EFFICIENCY. You can read more about this bug in this post on our Vkontakte group wall (on Russian).
Based on an average EFFICIENCY of the squadron's members. In order for a squadron to get to the Ranking, it has to have at least 15 players in our database.
At the time statistics is being updated once a day, so as not to burden the official website of the game. Later this period can decrease, if Gaijin provides us assistance.
This can be done only by commanders and officers. You must login, link the ingame character and go to the squadron page on the thunderskill. You should see the section "Settings ", where you can change the icon of the squadron.