| Subject | English | Icelandic |
| math. | asymptotic efficiency | asymptotic skilvirkni |
| math. | asymptotic relative efficiency | asymptotic hlutfallsleg hagkvæmni |
| math. | Bahadur efficiency | Bahadur skilvirkni |
| math. | Cramer-Rao efficiency | Cramér-Rao skilvirkni |
| stat. | Cramér-Rao efficiency | Cramér-Rao skilvirkni |
| comp., MS | efficiency bonus | bónuspunktar (In computer games, an additional score or points given for efficient play) |
| math. | efficiency equivalence | skilvirkni jafngildi |
| math. | efficiency factor | skilvirkni þáttur |
| math. | efficiency index | skilvirkni vísitölu |
| math. | Pitman efficiency | Pitman skilvirkni |
| stat. | power efficiency | hlutfallsleg nýting (of a test, á metilsins) |
| math. | power efficiency | nýtni |
| math. | power efficiency | hlutfallsleg hagkvæmni (af próf) |
| math. | relative efficiency of a test | hlutfallsleg hagkvæmni (af próf) |
| math. | relative efficiency of a test | nýtni |
| math. | relative efficiency of a sample design | hlutfallsleg nýting (sýnishorn hönnun) |