Cooperative production under diminishing marginal returns: Interpreting fixed-path methods

Fixed-path methods (FPMs) were introduced to manage situations where several individuals jointly operate a single technology (see [4]). In the production context, they consist in allocating marginal increments of output according to a proportions vector which changes along an arbitrary path. While very appealing from an incentives viewpoint under diminishing marginal returns, the asymmetry of these methods lacks solid economic interpretation. We provide such an interpretation by considering a situation where the technology to be shared results from the aggregation of private production processes. We propose a group-strategyproof mechanism under which no single agent wishes to secede from the partnership: the inverse marginal product proportions mechanism. It is the only FPM satisfying autarkic individual rationality; its path is uniquely determined by the technological contributions of the agents.