question: What ideas were utilized in von Neumann 's ecocomic model ?
answer: fixed-point theorems , linear inequalities , complementary slackness , and saddlepoint duality
turker_answer: Fixed-point theorems , linear inequalities , complementary slackness , and saddlepoint duality were utilized in von Neumann 's ecocomic model .
rule-based: Fixed-point theorems , linear inequalities , complementary slackness , and saddlepoint duality were utilized in von Neumann 's ecocomic model .