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.     

基于MATLAB的数字信号处理实践教学研究

数字信号处理是一门理论性较强的专业课程,公式推导多,学生对某些理论知识点理解困难。本文将MATLAB引入实践教学当中,对课堂教学、实验教学、课程设计等方面的实施实例进行阐述。本文提出的实践教学研究思路能对提高教学效果、提升学生的动手能力起到很好的促进作用。     

Effect of Secondary School Fees on Educational Attainment*

In this study, the heterogeneity of the fee abolition process in West German secondary schools is used to identify the effect of school fees on educational attainment and to obtain an estimate of the price elasticity of upper secondary education. The analysis is based on representative individual‐level data from three annual surveys of the German Mikrozensus. While coefficients cannot be estimated precisely, the results suggest that, on average, upper secondary school attainment increased by at least 8 percent in response to the fee abolition. The educational attainment of females appears to be more price sensitive than that of males.     

数控技术应用型人才调研及其岗位群分析

职业院校的数控技术应用专业,已经建设了近二十年,通过深入调研,了解机械制造企业人才状况,细致分析任职岗位群,掌握企业未来数控人才需求,为学院深入开展教学改革提供了可靠依据。     

高水平实验示范中心建设的探索与思考

本文就如何建立高水平的实验教学示范中心进行了探讨。通过实验室开放、实验课程改革、大型仪器设备共享,引进人才、重视实验技术人员队伍建设,以及示范中心网络信息平台建立等措施,建立具有生动、创新的实验课程,良好的实验效果、高素质稳定的实验队伍、方便、准确的信息交互平台的优秀实验教学示范中心。     

浅谈“数学模型实验”课程教学

对"数学模型实验"课程的教学模式进行了探讨,介绍了"数学模型实验"的教学内容、教学方法及考核方式,分析了目前该课程教学存在的问题并给出了相应的对策,最后探讨了该课程未来的发展方向。     

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.     

Temporal stability of preferences and willingness to pay for natural areas in choice experiments: A test–retest

The main objective of this paper is to test the temporal stability of stated preferences and willingness to pay (WTP) values from a Choice Experiment (CE) in a test–retest. The same group of participants was asked the same choice tasks in an internet-based CE, conducted twice with a time interval of one year without interviewer interference. We examine choice consistency at individual choice task level and transferability of the underlying indirect utility function and associated WTP values. The results show that choices are consistent in 57 percent of the choice occasions. Comparison of the choice models over time shows that the estimated preference and scale parameters are significantly different, suggesting that choice behaviour changed between the two surveys. Differences between marginal WTP estimates for individual choice attributes are statistically significant only at the 10 percent level. However, we show that this can result in significantly different WTP values for policy scenarios. The instability of estimated mean WTP values for different policy scenarios asks for caution when including WTP values in cost-benefit analysis.     

Teaching the Minimum Wage in Econ 101 in Light of the New Economics of the Minimum Wage

The author argues that the recent controversy over the effect of the minimum wage on employment offers an opportunity for teaching introductory economics. Research findings on the minimum wage could be used to motivate alternative models of the labor market, such as monopsony and search models, and to teach students how economists test hypotheses with data.     

Textbook Treatments of the Financial Market in the IS-LM Model

Intermediate macroeconomics textbooks introduce financial markets into the IS-LM analysis but typically as a beginning-of-period consideration. Here the financial market is introduced in an end-of-period model.