A Conceptual Model for Assessing the Minimum Size Area for an Area-Wide Integrated Pest Management Program

Table 2

Inequalities between factors determining the profitability of a control program. The letters stipulate the following: 𝑞: cost per unit area for the buffer zone, 𝐵; 𝑤: cost per unit area for the core area, 𝐴, as a proportion of 𝑞; 𝑣: value of the resource per unit area for the core area, 𝐴; 𝑒: value of the resource per unit area for the buffer, 𝐵, as a proportion of 𝑣.

𝑣>𝑞𝑤 and 𝑒𝑣>𝑞	𝑣>𝑞𝑤 and 𝑒𝑣<𝑞
Always profitable	Break-even exists
Parabola upright; roots negative or complex	Parabola upright; one positive root
𝑣<𝑞𝑤 and 𝑒𝑣>𝑞	𝑣<𝑞𝑤 and 𝑒𝑣<𝑞
Break-even exists	Never profitable
Parabola inverted; one positive root	Parabola inverted; no positive roots