Tendex, sometimes called Tendex index, is a basketball player
rating system. Credit for the system is attributed to
Dave Heeren, a sports writer from
Florida. The Tendex system is a linear rating system, in which relative player ratings are created based on a linear weighting of the various player
statistics.
The basic Tendex formula is often given as:
(POINTS + REBOUNDS + ASSISTS + STEALS + BLOCKS - Missed SHOTS - (Missed FREETHROWS)/2 - TURNOVERS - FOULS) / Played MINUTES
Criticism of the Tendex system is that it overvalues big men and does not give enough credit to guards. Therefore there is number of different variants. Some give more weight on steals, some don't divide the index by minutes, etc.
The Tendex index of 0.700 or above is consider to be the sign of superstardom. 1.000 is achievable too but far more rare. However, we have to keep in mind that if a player plays only a minute or two a very high rating may be resulted but it's hardly comparable with those who have played far more.
To give an example, I approximated Michael Jordan's Tendex: 0.672