Second-party and third-party punishment in a public goods experiment

We experimentally investigate whether third-party punishment is more effective than second-party punishment to increase public goods contribution. In our experiment, third parties first played the standard public goods game and then made punishment decisions as independent bystanders. We find that third parties punished more frequently, severely and less antisocially, resulting in a higher contribution level than that driven by second-party punishment. The third party’s exaggerated emotion towards free riders is proposed to explain their superior punishment effectiveness.     

Regulatory performance of audit tournaments and compliance observability

This paper examines the effectiveness of traditional regulatory schemes and newly emerging social information schemes for achieving compliance. Our experiment focuses on two stochastic audit schemes for enforcing regulatory compliance. In the Random Audit mechanism firms are randomly chosen for inspection. In the Tournament Audit mechanism the probability of inspection increases with the degree of estimated underreporting. To study the effects of social information, the experiment varies the observability of identity, output, and compliance decisions. Optimal output is theoretically independent of the auditing scheme, but equilibrium reporting is higher under the Tournament mechanism than Random auditing. Experimental findings are broadly consistent with the theoretical predictions for reporting, but deviate modestly for output. In particular, we find that average output is lower and reporting is higher in the Tournament treatment compared to the Random Audit treatment. At the individual level, a majority of participants misreported in most periods. Social observability does not affect output or reporting significantly in either of the audit treatments.     

基于计算实验的工程承发包模式选择机理分析

工程承发包模式是工程建设管理的重要组织方式，工程能否进行有效的目标控制及组织协调主要取决于承发包模式的选择。论文运用Multi-Agent方法建立了承发包模式选择的计算实验模型，通过具体数值算例分别分析了工程复杂度、业主能力及承包商水平对工程承发包模式选择路径的影响。研究结果表明：在工程复杂度越高、业主能力越弱情景下，业主选择DB模式的偏好就越大；提升承包商水平和培育有序的DB建设市场环境是提高业主选择DB模式偏好的重要途径。研究结论为业主的承发包模式选择、行业政策制订提供了参考依据。     

生物工程大实验课程改革与探讨

生物工程大实验是生物工程专业的一门重要的综合性实验课程,就当前生物工程大实验教学存在的几点问题,从实验内容、实验体系、实验方法、考核方式方面对生物工程大实验进行改革与探讨。     

Economic corollaries of personalized recommendations

The impact of recommendation systems (RSs) on the diversity of consumption is not transparent or well understood. Available studies, whether experimental or theoretical, show inconsistent and even opposite results, which manifests as debate in the literature. In this paper, we investigate the impact of two main recommender systems, neural collaborative filtering and deep content filtering, on sales diversity via a randomized field experiment. Our results confirm the capability of recommender engines in increasing or decreasing aggregate sales diversity. Nonetheless, they amplify homogenization and reduce individual-level consumption diversity. In conclusion, our research reconciles seemingly contradict previous findings and illustrates that the design of the RS is the decisive factor in homogenizing or diversifying product sales.     

$$\mathcal{D}$$-optimal Minimum Support Mixture Designs in Blocks

An easy method to construct efficient blocked mixture experiments in the presence of fixed and/or random blocks is presented. The method can be used when qualitative variables are involved in a mixture experiment as well. The resulting designs are -optimal in the class of minimum support designs. It is illustrated that the minimum support designs are more efficient than orthogonally blocked mixture experiments presented in the literature and only slightly less efficient than -optimal designs.     

密封胶在拉索索端结构中的应用研究

索端结构是拉索的防护薄弱环节,在索端结构中增加密封胶措施是索端密封的一次探索。选取了几种不同的密封胶分别与拉索聚乙烯护套进行粘结,对提高斜拉索的耐久性和安全性有一定的意义。     

建立县级公共气象服务体系的实践与思考

介绍了德庆县气象局开展公共气象服务系统试点改革的具体实施情况,分析了试点中遇到的一些问题,探索如何建立以发展现代农业气象服务为主的县级农村公共气象服务体系。     

数字电子技术基础实验教学现状的探讨

数字电子技术基础是工科电子类专业学生的一门重要的专业基础课程。本文首先探讨了当前实验教学中存在的一些问题:教学观念落后、教学内容陈旧、教学方式僵化、考核模式单一。然后针对这些问题提出了具体解决方法:转变"重理论,轻实践"的观念、更新实验内容、转变实验教学方式、改进实验考核方式。这些方法可为数字电子技术基础实验教学的改革提供参考。     

机制砂的性能及其对混凝土性能的影响

以往对混凝土的研究,土木工作者把更多的注意力放在了水泥、水灰比、外加剂以及粉煤灰和硅灰等外掺材料上。集料也是混凝土的重要组成部分,在混凝土中占有很重要的地位。随着土木建设的日趋发展和完善,天然砂日益紧缺,我们应重新审视集料对混凝土性能的影响。本文就着手研究用机制砂取代河砂对混凝土性能的影响。