▁to ▁include ▁instances ▁of ▁the ▁total ▁re venue ▁function ▁that , ▁for ▁the ▁specific ▁allocation , ▁yields ▁a ▁re venue ▁smaller ▁than ▁the ▁critical ▁re venue . ▁ ▁The ▁robust ness ▁measures ▁the ▁imm unity ▁of ▁a ▁decision ▁to ▁failure . ▁A ▁robust ▁satisf ic er ▁is ▁a ▁decision ▁mak er ▁that ▁pre fers ▁choices ▁with ▁higher ▁robust ness . ▁ ▁If , ▁for ▁some ▁allocation ▁, ▁the ▁correlation ▁between ▁the ▁critical ▁re venue ▁and ▁the ▁robust ness ▁is ▁illustrated , ▁the ▁result ▁is ▁a ▁graph ▁somewhat ▁similar ▁to ▁that ▁in ▁Figure ▁ 7 . ▁This ▁graph , ▁called ▁robust ness ▁curve ▁of ▁allocation ▁, ▁has ▁two ▁important ▁features , ▁that ▁are ▁common ▁to ▁( most ) ▁robust ness ▁curves : ▁▁ ▁The ▁curve ▁is ▁non - in cre asing . ▁This ▁capt ures ▁the ▁notion ▁that ▁when ▁higher ▁requirements ▁( high er ▁critical ▁re venue ) ▁are ▁in ▁place , ▁failure ▁to ▁meet ▁the ▁target ▁is ▁more ▁likely ▁( lower ▁robust ness ). ▁This ▁is ▁the ▁trade off ▁between ▁quality ▁and ▁robust ness . ▁ ▁At ▁the ▁nom inal ▁re venue , ▁that ▁is , ▁when ▁the ▁critical ▁re venue ▁equals ▁the ▁re venue ▁under ▁the ▁nom inal ▁model ▁( the ▁estimate ▁of ▁the ▁re venue ▁functions ), ▁the ▁robust ness ▁is ▁zero . ▁This ▁is ▁since ▁a ▁slight ▁deviation ▁from ▁the ▁estimate ▁may ▁decrease ▁the ▁total ▁re venue . ▁ ▁If ▁the ▁robust ness ▁curves ▁of ▁two ▁alloc ations , ▁ ▁and ▁ ▁are ▁compared , ▁the ▁fact ▁that ▁the ▁two