技术中介在技术交易服务中是否存在下沉倾向——基于买方选择视角的验证

技术要素转移与交易对技术中介有较强的依赖性，而技术中介的存在能够有效降低交易过程中的信息失衡，为买方交易提供必要支持，技术中介服务直接影响技术交易效率。当代技术中介服务已经形成较大规模，提供服务的种类也较为全面，整体上适应了技术市场发展需要。但是，由技术中介参与的大量交易都存在低端化倾向，据此提出中介服务下沉化假设，并构建选择影响因素模型。通过对买方企业数据的采集与回归，发现无论是全样本还是分类样本均有效验证了主要假设变量。因此，为保障技术中介合理发展，从政策层面应重点关注如何提升服务质量，使其服务于中高端技术交易需求。     

中国城市科技人才集聚促进了全要素生产率增长吗——来自285个地级市的经验研究

基于2005—2018年中国内地285个地级市数据，对城市科技人才集聚与全要素生产率（简称“TFP”）进行测度分析，实证考察科技人才集聚对TFP的影响。结果表明：①城市科技人才集聚与TFP空间分异特征显著，但二者具有较强的时空一致性，即科技人才集聚特征显著的城市，其TFP也相对稳定；②城市科技人才集聚对TFP的影响呈倒U型，但研究期内大多数城市仍处于集聚效应占主导阶段,科技人才集聚通过提升城市技术进步水平促进TFP增长，而科技人才集聚对技术效率的影响呈倒U型；③不同类型城市科技人才集聚对其TFP影响的异质性显著，且适宜集聚区间也存在差异。省会城市及一、二线城市等优势特征显著的城市所能承受的科技人才集聚规模上限更高，有利于通过释放集聚红利促进TFP增长，而非省会城市、三线及以下城市等则拐点值较低。     

东部地区十省市规模以上工业企业研发投入绩效评价

选取2021年度数据，采用数据包络分析（DEA）方法对中国东部地区10个省份规模以上工业企业的研发投入绩效进行评价，并采用灰关联分析方法分析确定各项研发投入产出指标相对于DEA效率的灰色关联度。研究结果表明，80%的省份规上工业企业研发投入产出处于非DEA有效状态，存在不同程度的投入冗余或产出不足；规上工业企业发明专利申请数与研发投入产出效率的关联度最高，其次是新产品销售收入和R&D经费内部支出。     

Post-script—Retail forecasting: Research and practice

This note updates the 2019 review article “Retail forecasting: Research and practice” in the context of the COVID-19 pandemic and the substantial new research on machine-learning algorithms, when applied to retail. It offers new conclusions and challenges for both research and practice in retail demand forecasting.     

The diffusion of mobile payments: Profiling the adopters and non-adopters,Roger's way

This study aims to establish various market segments based on consumers' attitudinal elements influencing the adoption of mobile payments (m-payments). It also examines the best discriminators between identified clusters of m-payment users. Three hundred and sixty m-payment users participated in the study. Cluster and discriminant analyses were employed for the analysis. The findings suggest that two segments are established, and strategies can be developed accordingly. The study provides marketers with numerous touchpoints to propagate the adoption of m-payment apps. It also comprehensively explains m-payment users in developing economies by superimposing the cohorts to Roger's diffusion of innovation model.     

The origins of agricultural inheritance traditions

We investigate the origins of agricultural inheritance traditions, equal partition and primogeniture. Our case study is the German state of Baden-Württemberg. Our empirical findings suggest that rural inheritance traditions were primarily determined by geography. First, fertile soils allowed splitting of the land among siblings for longer and with fewer conflicts, and hence we find more equal partition in areas with higher soil quality, especially at elevation levels conducive to intensive agriculture. Second, geography determined the settlement pattern. Areas that were settled before the Middle Ages, when land was abundant and free, are more likely to apply equal partition today. In areas that were largely uninhabited until the Middle Ages, primogeniture is the norm. We argue that these areas were deforested with the obligation of primogeniture, imposed by feudal lords.     

Obesity of politicians and corruption in Ukraine in 2000–2020– Reply

We collected 469 frontal face images of Ukrainian cabinet ministers who were in office in 2000–2020. For each image, the minister's body mass index was estimated using a computer vision algorithm. The time series of median estimated body mass index of cabinet ministers co-moves over time with two existing measures of corruption – World Bank worldwide governance indicator Control of Corruption, and the discrepancy between the quantity of luxury wristwatches exported from Switzerland to Ukraine (reported by Swiss statistics) and the corresponding quantity imported by Ukraine from Switzerland (reported by Ukrainian statistics).     

实现2035年发展目标的潜在增长率*

党的十九届五中全会提出了到2035年人均GDP达到中等发达国家水平的远景目标，因此测算和回答能否和如何如期实现该目标，对于我国实现第二个百年奋斗目标和坚持“四个自信”具有重要的意义。为此，本文根据跨越和陷入“中等收入陷阱”经济体的发展经验，对2021—2035年我国潜在增长率变化进行了测算。一是参照跨越和陷入“中等收入陷阱”经济体在我国相同发展阶段时各主要生产要素的变化，模拟设定我国未来各主要生产要素的增长率；二是通过运用附加人力资本的增长核算模型测算基准、乐观和悲观三种不同情境下未来我国经济的潜在增长率，验证我国2035年发展目标实现的可能性；三是依据主要要素对潜在增长率的贡献度，提出我国如期实现2035年发展目标的相应政策建议。     

Green consumption behavior prediction based on fan-shaped search mechanism fruit fly algorithm optimized neural network

Predicting consumption behavior is very important for adjusting supplier production plans and enterprise marketing activities. Conventional statistical methods are unable to accurately predict green consumption behavior because it is characterized by multivariate nonlinear interactions. The paper proposes an optimized fruit fly algorithm (FOA) and extreme learning machine (ELM) model for consumption behavior prediction. First, to address the problem of uneven search direction of FOA leading to insufficient search ability and low efficiency, the paper proposes a sector search mechanism instead of a random search mechanism to improve the global search ability and convergence speed of FOA. Second, to address the issue that the initial weights and hidden layer bias values of the ELM are randomly generated, which affects the learning efficiency and generalization of the ELM, the paper uses an improved FOA to optimize the weights and bias values of ELM for improving the prediction accuracy. Taking the green vegetable consumption behavior of Beijing residents as an example, the results show the optimization of the initial weight and threshold of ELM by the GA, PSO, FOA, and SFOA, the prediction accuracy of the GA-ELM, PSO-ELM, FOA-ELM, and SFOA-ELM models all surpass those of ELM. Compared with BPNN, GRNN, ELM, GA-ELM, PSO-ELM, and FOA-ELM models, the RMSE value of SFOA-ELM was decreased by 9.45%, 8.40%, 11.89%, 5.84%, 2.22%, and 2.69%, respectively. These findings demonstrate the effectiveness of the SFOA-ELM model in green consumption behavior prediction and provide new ideas for the accurate prediction of consumption behaviors of other green products with similar characteristics.