Maximizing benefits in project selection: a hybrid approach

Charitable foundations and government programmes should endeavour to allocate their limited resources to best serve their constituents. Yet, mathematical programming techniques are rarely used despite overwhelming evidence of their superiority in selecting projects that yield higher levels of total benefits. We present a novel ‘hybrid selection model’ that combines binary linear programming and heuristic rank-based models applied to two case studies. The first case focuses on providing services to women and shows a hybrid model would have selected the top three ‘signature’ projects and maintained an above-average overall project benefit while securing a 180% improvement in the number of projects funded, a 66% improvement in the number of women served and a 132% improvement in the total benefit achieved. In the second case, we apply the hybrid approach to data from the US government’s largest forest preservation programme and demonstrate that the hybrid approach could allow the programme to select up to 11 top-scoring projects while still achieving a 97% gain in the total overall benefit compared to their traditional method. These case studies show that the hybrid approach has the potential to be applied in a variety of settings and improve how foundations and programmes achieve their goals.     

论海湾河口水环境治理制度建设的理论基石

通过对经济学与管理学的相关文献与理论的梳理分析,提出海湾河口水环境治理制度建设的四块理论基石:海岸带综合管理理论、湖泊流域水环境管理理论、环境产权理论、合作型环境治理理论,以期为建立海湾河口水环境治理制度体系提供理论依据和指导。     

巢湖派河流域清水廊道技术产业推广模式的构建

派河为巢湖一级支流，水质差，针对派河流域开展了多项研究，产生了多项清水廊道技术，尚缺乏有效的产业化推广模式，基于此，构建了多层次、多元化清水廊道技术产业推广模式（“2S”VIP）。该模式包括组织机构、运行机制、推广模式平台、保障措施等。其中清水廊道技术推广模式平台包括综合技术信息平台、综合服务平台、产业化推广平台，以综合技术信息平台为支撑，以互联网+、大数据等为手段，综合服务平台为依托，产业化推广平台实现技术与市场的衔接。在政府的引导和监督下，通过一系列保障措施使各平台能顺利运行，达到产、学、研、用的有机融合。     

Integrated planning for product selection,shelf-space allocation,and replenishment decision with elasticity and positioning effects

As the retail industry is growing larger and more diversified, retailers' decisions about product selection, shelf-space-allocation, and replenishment become more important and challenging. This paper is to present a model for shelf-space allocation with product selection and replenishment decisions to maximize the retailer's profit. The model is based on a two-dimensional display space in which all shelves and products have widths and heights and includes factors that influence demand for each product, such as space and cross-space elasticities and positioning effects. The integrated model presented is mixed-integer non-linear programming (MINLP) because the demand function is non-convex. This research proposes two heuristic algorithms (tabu search and genetic) to solve the MINLP problem. The results show the effectiveness and efficiency of these algorithms by comparing the outputs to the MINLP optimal solution for small data sets and comparing the algorithm performances for large data sets. The solution methodologies expect to support a simultaneous decision-making process for retailers to maximize their revenue.     

Optimal allocation of direct and embodied arable land associated to urban economy: Understanding the options deriving from economic globalization

Land resources do not flow directly but can be allocated as “embodied land” in goods and services during economic globalization. The term “embodied arable land” can help link local land allocation strategies to the global and national supply chains and trade activities, and suggest new lens in optimizing arable land allocation. China is facing a serious arable land shortage, especially in municipal administrative areas. Based on the nested input-output analysis (Nested IOA), this work takes Shanghai as an example, exploring the allocation of direct and embodied arable land of an urban economy within the process of economic globalization. The amount of embodied arable land associated with Shanghai economy is 6.09 Mha, broken down into local arable land use (0.20 Mha), domestic inflows (3.20 Mha) and foreign inflows (2.69 Mha). This area supports local final demand (4.32 Mha), domestic outflows (1.24 Mha) and foreign outflows (0.53 Mha). Land-related imbalances emerge in the study, namely the economy’s demand versus the city’s size, the arable land demand versus supply, and embodied arable land inflows versus outflows. Regarding the role of the urban economy in allocation of global arable land under economic globalization, on the one hand, Shanghai has intensively involved with a large amount of embodied foreign arable land resources, and has been heavy dependent on foreign embodied arable land; On the other hand, there is still large potential for Shanghai to take the opportunity of economic globalization for an optimal allocation of direct and embodied arable land. Policy suggestions on taking the opportunity of economic globalization for an optimal allocation of direct and embodied arable land are put forward.     

Random mechanisms for house allocation with existing tenants

We study the house allocation problem with existing tenants: $n$ houses (stand for “indivisible objects”) are to be allocated to $n$ agents; each agent needs exactly one house and has strict preferences; $k$ houses are initially unowned; $k$ agents initially do not own houses; the remaining $n-k$ agents (the so-called “existing tenants”) initially own the remaining $n-k$ houses (each owns one). In this setting, we consider various randomized allocation rules under which voluntary participation of existing tenants is assured and the randomization procedure either treats agents equally or discriminates against some (or all) of the existing tenants. We obtain two equivalence results, which generalize the equivalence results in Abdulkadiroğlu and Sönmez (1999) and Sönmez and Ünver (2005).     

苏北地区农业完全成本水价农户承受力调查——基于水源地生态补偿的视角

南水北调东线一期工程江苏段的主要目标是向苏北供水,缓解该地区的农业用水短缺问题。但现行农业水价未考虑水源区的机会成本损失,不利于调动水源区环境保护积极性。论文设计单边界CVM引导技术,估算了苏北农户以提高农业水价的方式对水源区生态补偿的支付意愿。研究发现,苏北农户生态补偿支付意愿为7.63元/亩,但在不同作物种植结构和不同城市存在较大异质性。未来3年内,苏北农业用水每年所提供的生态补偿资金总额在1.526~1.679亿元之间。在发达地区探索构建绿色导向的农业水价体系有利于为其他地区提供先行示范效应。