Abstract
First this paper indicates the fault common to the analysis given by three professors as to the Deposit-Refund System, and then provides a (much better?) alternative model for Deposit-Refund Theory. In their papers, all three professors have adopted two-stage construction. In the first stage the economic subject demands soft-drink cans following the utility-maximizing rule qua consumer (Jekyll), and then, in the second stage, he suddenly turns into entrepreneur (Hyde) and pursues his profit following the marginal cost-price rule, completely independent of the former behavior. (In Prof. Fujioka's paper, he firstt appears as Hyde. Then transformation into Jekyll!) Their analyses only place a utility-maximizing behavior and a profit-maximizing behavior in juxtaposition completely independent of each other. Such dissociation should not be overlooked. Alternatively a simple (and much better?) model of a unified Deposit-Refund Theory is proposed, which incorporates toil and trouble attendant on refunding into utility function as disutility, together with including the refunded money into the budget equation.
