Eks see üks ähmasevõitu mõiste ole.
Wikipedia ütleb "Efficiency (basketball)" kohta nii (loodan, et kõigil lugejail keeled suus): "In professional basketball, the most commonly used statistical benchmark for comparing the overall value of players is called efficiency. It is a composite basketball statistic that is derived from basic individual statistics: points, rebounds, assists, steals, blocks, turnovers and shot attempts. The efficiency stat, in theory, accounts for both a player's offensive contributions (points, assists) and his defensive contributions (steals, blocks), but it is generally felt that efficiency ratings favor offense-minded players over those who specialize in defense."
Põhimõtteliselt kogu kupatus kokku: kui palju (või vähe) head su mängija tiimile teeb, kui efektiivne ehk tõhus ka platsil on.
Ega ma ise ka päris täpselt tea, kuidas seda arvutatakse, ülaltoodu on pigem loogilise arutelu ja Wiki suure panuse tulem. Loodan, et pisut ikka abi oli. Ehk on teised targemad. :)