Crowd-sourcing with uncertain quality - an auction approach

This article addresses two important issues in crowd-sourcing: ex ante uncertainty about the quality and cost of different workers and strategic behaviour. We present a novel multi-dimensional auction that incentivises the workers to make partial enquiry into the task and to honestly report quality-cost estimates based on which the crowd-sourcer can choose the worker that offers the best value for money. The mechanism extends second score auction design to settings where the quality is uncertain and it provides incentives to both collect information and deliver desired qualities

A Performance and Resource Consumption Assessment of Secure Multiparty Computation

In recent years, secure multiparty computation (SMC) advanced from a theoretical technique to a practically applicable technology. Several frameworks were proposed of which some are still actively developed. We perform a first comprehensive study of performance characteristics of SMC protocols using a promising implementation based on secret sharing, a common and state-of-the-art foundation. Therefor, we analyze its scalability with respect to environmental parameters as the number of peers, network properties -- namely transmission rate, packet loss, network latency -- and parallelization of computations as parameters and execution time, CPU cycles, memory consumption and amount of transmitted data as variables. Our insights on the resource consumption show that such a solution is practically applicable in intranet environments and -- with limitations -- in Internet settings

Short Communication: DEA based auctions

In this paper we introduce a simulation framework which we use to numerically evaluate the Hybrid DEA - Second Score Auction. In a procurement setting, the winner of the Hybrid auction by design receives payment at the most equal to the second score auction. It is therefore superior to the traditional second score scheme from the point of view of a principal interested in acquiring an item at the minimum price without losing in quality. For a set of parameters we quantify the size of the improvements. We show in particular that the improvement depends intimately on the regularity imposed on the underlying cost function. In the least structured case of a variable returns to scale technology, the hybrid auction only improved the outcome for a small percentage of cases. However, for those few cases the improvement introduced by the hybrid auction is signicant. For other technologies with constant returns to scale, the gains are considerably higher and payments are lowered in a large percentage of cases. In the simulations, we furthermore calculate the eect of the number of the participating agents, the concavity of the principal value functions, and the number of quality dimensions

Short Communication: DEA based auctions

In this paper we introduce a simulation framework which we use to numerically evaluate the Hybrid DEA - Second Score Auction. In a procurement setting, the winner of the Hybrid auction by design receives payment at the most equal to the second score auction. It is therefore superior to the traditional second score scheme from the point of view of a principal interested in acquiring an item at the minimum price without losing in quality. For a set of parameters we quantify the size of the improvements. We show in particular that the improvement depends intimately on the regularity imposed on the underlying cost function. In the least structured case of a variable returns to scale technology, the hybrid auction only improved the outcome for a small percentage of cases. However, for those few cases the improvement introduced by the hybrid auction is signicant. For other technologies with constant returns to scale, the gains are considerably higher and payments are lowered in a large percentage of cases. In the simulations, we furthermore calculate the eect of the number of the participating agents, the concavity of the principal value functions, and the number of quality dimensions

Multi-dimensional auctions under information asymmetry for costs and qualities

This paper discusses the design of a novel multi-dimensional mechanism which allows a principal to procure a single project or an item from multiple suppliers through a two-step payment. The suppliers are capable of producing different qualities at costs which cannot exceed a certain value and the mechanism balances between the costs faced by the suppliers and the benefit the principal achieves from higher qualities. Iniatially, the principal implements a standard second score auction and allocates the project to a single supplier based its reported cost and quality, while then it elicits truthful reporting of the quality by issuing a symmetric secondary payment after observing the winner’s production. We then provide an alternate mechanism in which the principal issues an asymmetric secondary payment which rewards agents for producing higher qualities, while it penalises them for producing lower qualities than they reported. We prove that for both mechanisms truthful revelation of costs and qualities is a dominant strategy (weakly for costs) and that they are immune to combined misreporting of both qualities and costs. We also show that the mechanisms are individually rational, and that the optimal payments received by the winners of the auctions are equal to the payment issued by the standard second score auction

Multi-dimensional auctions under information asymmetry for costs and qualities

This paper discusses the design of a novel multi-dimensional mechanism which allows a principal to procure a single project or an item from multiple suppliers through a two-step payment. The suppliers are capable of producing different qualities at costs which cannot exceed a certain value and the mechanism balances between the costs faced by the suppliers and the benefit the principal achieves from higher qualities. Iniatially, the principal implements a standard second score auction and allocates the project to a single supplier based its reported cost and quality, while then it elicits truthful reporting of the quality by issuing a symmetric secondary payment after observing the winner’s production. We then provide an alternate mechanism in which the principal issues an asymmetric secondary payment which rewards agents for producing higher qualities, while it penalises them for producing lower qualities than they reported. We prove that for both mechanisms truthful revelation of costs and qualities is a dominant strategy (weakly for costs) and that they are immune to combined misreporting of both qualities and costs. We also show that the mechanisms are individually rational, and that the optimal payments received by the winners of the auctions are equal to the payment issued by the standard second score auction

Short Communication: DEA based auctions

In this paper we introduce a simulation framework which we use to numerically evaluate the Hybrid DEA - Second Score Auction. In a procurement setting, the winner of the Hybrid auction by design receives payment at the most equal to the second score auction. It is therefore superior to the traditional second score scheme from the point of view of a principal interested in acquiring an item at the minimum price without losing in quality. For a set of parameters we quantify the size of the improvements. We show in particular that the improvement depends intimately on the regularity imposed on the underlying cost function. In the least structured case of a variable returns to scale technology, the hybrid auction only improved the outcome for a small percentage of cases. However, for those few cases the improvement introduced by the hybrid auction is signicant. For other technologies with constant returns to scale, the gains are considerably higher and payments are lowered in a large percentage of cases. In the simulations, we furthermore calculate the eect of the number of the participating agents, the concavity of the principal value functions, and the number of quality dimensions