Player who plays small number of games and achieves relatively high MMR on Pro Ladder is often called ‘efficient’. Player who plays a lot and achieves mediocre or weak results is commonly called ‘spammer’. This last name is not too kind, as low efficiency is also a typical domain of streamers, memers, and simply people enjoying playing the game more than squeezing every single point.

Anyway, Gwent Masters website gives only two numbers describing player’s efficiency: peak MMR and number of games. On this basis, we would like to define as simple measure of efficiency as possible. Think of BMI (Body Mass Index) you’ve probably already come across. BMI says how thick you are in real life, based on height and weight, LEI would tell how thick you are in Gwent 😉

The intuitive first try is taking MMR and dividing by no. of games. It would not work due to placements however, beacuse MMR gain is way faster before placements are done. So we have to include only surplus MMR: MMR – 9600(minimal placements score). Index defined this way could already work fine, but justice demands taking into account that games on high MMRs are harder and less rewarding than on low. The simplest operation to account for this effect is squaring surplus MMR, which gives the same effect as taking square root of no. of games, while the final number will be smaller and prettier in the latter case. So here we are: LEI = surplus MMR / sqrt(no. of games).