завышен(ный)

Завышен(ный) -- on the high side, high, too high; non-conservative (когда завышение величины в расчёте приводит к снижению надёжности); pessimistic, optimistic (когда завышение величины приводит соответственно к необоснованно пессимистическим и оптимистическим выводам)

 The calculated phase velocities are all on the high side.

 The predictions based on the linear rule, by contrast, tended toward nonconservative results.

 The quality of the sample for SAE = 11 is suspect and this number is likely to be very pessimistic.

 This estimated life should be more than that realized and is thus optimistic. (... должна получаться больше фактической, т.е. необоснованно высокой)

Завышен на

 His results for ks are high by 20-35 percent.

 The trend is being predicted though the absolute values are about 20 percent too high.

 Although the latter correlation yielded better agreement with the data then did the former, it was still 15 percent high.

—завышен на величину, превышающую

—несколько завышен