combinatorial theory的用法和样例：
例句
- Markowitz portfolio theory has become the footstone of modem finance theory.
摘要马柯维茨的投资组合理论奠定了现代金融理论的基石。 - The optimization model of multi-product inventory with chance constrained attributes based on behavioral portfolio theory is established, which are solved as well.
结合行为证券投资组合理论建立了一种具有机会约束属性的多产品库存优化模型，并给出了其求解算法。
