Li, Shiyin A mathematical method for determining the optimal quantity of natural enemies of a pest species to raise. (Chinese. English summary) Zbl 1055.92519 J. Biomath. 14, No. 2, 192-196 (1999). Summary: A dynamic model of pests’ population quantity with random rise and fall as the environment varies was evaluated by using the methods of Itô stochastic differential equations. A formula to determine the optimal quantity of the pests’ natural enemies for biological control was proposed by using the method of finding the minimal value, and a statistical method to determine the parameters in the formula was pointed out. MSC: 92D40 Ecology 92D30 Epidemiology Keywords:pest population; Itô stochastic differential equation; optimal raising quantity of pests’ natural enemy PDFBibTeX XMLCite \textit{S. Li}, J. Biomath. 14, No. 2, 192--196 (1999; Zbl 1055.92519)