Economics and underdetermination: a case study of urban land and housing economics

Underdetermination, associated with the Duhem–Quine thesis,is a familiar if under-researched theme in economics. In thelight of this, we examine the development of urban land andhousing economics. Through its Cartesian dualistic delineationof theory and data, the contemporary mainstream approach appearsunable to circumvent the problem of underdetermination. In effect,it employs the strong version of Duhem–Quine in its retentionof the assumption of a single, unitary competitive market (andassociated access–space trade-off). Conversely, we highlightthe affinity of Ely's (and the later Columbia School's) approachto pragmatists Dewey and Peirce, which provides a more fruitfulbasis for explanation.     

Who's in charge of the central city? The conflict between efficiency and equity in the design of a metropolitan area

A circular metropolitan area consists of a central city surrounded by a suburb. Households sort over the two jurisdictions based on public service levels and their costs of commuting to the metropolitan center. Using numerical simulations, we show that (1) there typically exist two equilibria: one in which the poor form the voting majority in the central city and the other in which the rich form the majority in the central city; (2) there is an efficiency vs. equity trade-off as to which equilibrium is preferred; and (3) if the central city contains only poor households, equity favors expanding the central city to include rich households. The third result arises not because of a fiscal subsidy from rich to poor households induced by a property tax but rather because of a change in house price capitalization.     

中国外商直接投资的区位决定因素分析:城市数据

本文以全国210个地级以上城市为对象,分析了外商直接投资的区位决定因素。本文采用OLS和逐步回归分析方法以及2002年的横截面数据,在以往研究的基础上选择四项区位决定因素包括三种成本因素、三种市场因素、四种集聚因素和四种制度因素进行实证研究。结果表明,劳动力成本对各城市的外商直接投资的区位选择影响不明显,而市场规模、基础设施、教育和研究开发条件以及地方金融规模对外商直接投资的区位选择的影响具有显著性。本文的逐步回归分析结果还表明,就东部地区而言,能源条件和市场规模是较重要的区位决定因素;就中西部地区而言,市场规模、基础设施、教育和研究开发条件以及地方金融成为较重要的区位决定因素。     

Assessing terrestrial wildlife populations in the Toronto and Region Area of Concern

Beneficial use impairments (BUIs) under the Great Lakes Water Quality Agreement identify environmental issues requiring remedial action within the Great Lakes Areas of Concern (AOCs). We conducted this study to support the assessment of the wildlife component of BUI 3: degradation of fish and wildlife populations. We compared bird and amphibian (frogs and toads) data from the Toronto and Region Conservation Authority’s Terrestrial Long-term Monitoring Program in the Toronto and Region AOC to an adjacent, but otherwise similar, reference watershed, Duffins Creek. Twelve of 13 targets were met within the AOC for forest bird, wetland bird, meadow bird and amphibian populations based on averages of mean annual values at sites within the AOC that were within two standard deviations of averages at sites in the Duffins Creek reference watershed between 2008 and 2017. Even though wildlife populations within the AOC were within the normal range of variability expected from a reference watershed, they were often at lower levels than within the Duffins Creek reference watershed. In addition, forest bird and amphibian populations were negatively affected by urbanization within the AOC and meadow bird indices declined. We conclude that while wildlife populations within the AOC currently meet targets for BUI 3, they continue to be negatively impacted by numerous stressors that are primarily related to past and ongoing urbanization. Thus, continued restoration of wildlife habitat and protection of existing habitat within the AOC is highly recommended.     

The topography of metropolitan employment: Identifying centers of employment in a polycentric urban area

While it is well recognized that US metropolitan areas are polycentric, there is little consensus as to the appropriate method for identifying concentrations of employment within them. Existing methods suffer from strong assumptions about parametric form, misspecification, or reliance on local knowledge to calibrate model parameters. This paper introduces a new nonparametric method for identifying subcenters. Results indicate that this, more flexible, nonparametric approach yields greater accuracy with regard to both urban and suburban centers compared with other approaches. This approach should provide better data for the numerous topics that depend on the spatial accounting of employment within metropolitan areas.     

我国城乡耐用消费品市场用户构成差异的研究——一个创新扩散的视角

创新扩散理论按照用户采用新产品的时间先后顺序将市场细分为创新者、早期采用者、早期大多数、晚期大多数和落后者五种类型。本文在扩散经典理论和中国市场特征的基础上,提出城镇市场和农村市场耐用消费品用户构成差异的假设。研究结果证实了全部假设:城镇的创新者比例显著高于农村,农村的早期采用者比例显著超过城镇,而各类型采用者的采用持续时间农村全面长于城镇。这些结论为更加深入地了解二元经济结构下中国市场的特征提供了有益启示。     

Land use externalities, open space preservation, and urban sprawl

Parcel data on residential land conversion are used to investigate how land use externalities influence the rate of development and modify policies designed to manage urban growth and preserve open space. Several “smart growth” policies are found to significantly influence land conversion, including a development clustering policy that concentrates development and generates preserved open space. In addition to directly affecting a parcel's hazard rate of conversion, this policy is found to affect neighboring parcels' conversion by generating a positive open space externality that hastens their development. The implication that the clustering policy could generate a more sprawled pattern of development is explored using spatial simulation.     

中国城市住宅市场的结构差异性分析

市场价商品房、经济适用住房和廉租房构成了目前中国城市住宅市场的供应体系.依据中国30个主要城市的房地产开发统计数据,选择吸纳率作为评价住宅市场供需均衡状态的指标,利用固定影响变截距模型,重点研究了商品房和经济适用住房供给结构的城市差异性.研究发现,在城市住宅市场中,经济适用住房市场和商品房市场具有很强的相关性.作为具有政府资助性质的经济适用住房建设,存在典型的地域性特征,其政策的设定和实施会对整个住宅市场产生影响,地方政府应在利用比较全面的住宅市场指标体系进行综合分析基础上,制定适合本地的经济适用住房政策.     

城市可持续发展能力成长过程理论解析

城市可持续发展是国家和地区可持续发展的核心和关键，城市可持续发展能力则是城市可持续发展的基础依托和潜在支撑。促进城市可持续发展能力的持续、快速、健康成长是实现国家和地区可持续发展以及构建和谐社会的必由之路。城市可持续发展能力相关课题的理论与实证研究必须着眼于城市可持续发展能力成长的时空过程周此，对城市可持续发展能力成长过程进行理论分析和探讨就显得尤为必要。     

Diets,population structure,and seasonal activity patterns of mudpuppies (Necturus maculosus) in an urban,Great Lakes coastal habitat

Freshwater species native to the Laurentian Great Lakes region face numerous environmental stressors, and the conservation status and ecological relationships of many remain poorly understood. One such species, the mudpuppy (Necturus maculosus), is declining, but better information on their natural history and development of more effective population monitoring techniques is needed. We assessed seasonal variation in capture success, biases in capture techniques, and feeding ecology of mudpuppies in Wolf Lake, a highly perturbed and urban former estuarine wetland complex to Lake Michigan. Trapping periods of ≥ 3 consecutive nights occurred from January to May 2015, and October 2015 to March 2016. Overall trapping success differed among trapping periods (p = 0.01) and declined precipitously at water temperatures above 14.1 °C (p < 0.001). Mudpuppies in traps (mean 26.9 ± 0.5 cm) were larger than those caught with hand nets (mean 14.7 ± 0.8 cm, p < 0.0001), suggesting that multiple methods may be needed to accurately assess demographics. Stomach contents obtained through gastric lavage included mollusks, leeches, insects, isopods, amphipods, crayfish, fish, a frog, and a juvenile conspecific. Invasive species, including rusty crayfish (Orconectes rusticus), round gobies (Neogobius melanostomus), and zebra/quagga mussels (Dreissena spp.) were present in guts, suggesting mudpuppy foraging has changed along with aquatic communities in the region. Prey community analyses revealed differences in overall diet among size classes of mudpuppies (p = 0.001), but relatively weak similarity within size classes. Results suggest that mudpuppies in lake ecosystems occupy a broad niche that changes as they grow.