东北地区农业系统资源利用方式及其效益的历史变迁

历史上东北地区水草丰沛,森林茂密,沼泽遍地。生息繁衍于此的东北先民,或渔猎,或游牧,或农耕。明清以来,尤其是清中期实行招垦政策以来,东北地区的荒田、草地、山林、沼泽,均得到了大面积的农业开发,造成农田系统对草地系统、森林系统、沼泽系统不断包抄与逐渐挤压,深刻影响了东北地区的作物布局与耕地制度。受此影响,东北地区种植业系统功能日益强化,而畜牧业系统、林业系统以及渔猎系统功能呈日渐式微趋势,外来移民的大量涌入以及放垦政策的大力推行难辞其咎。     

住宅价格如何影响城镇居民消费——基于状态空间模型的研究

基于时变参数状态空间模型,利用1999年到2016年的季度数据测算了我国住宅价格对城镇居民消费影响的时变特征。结果表明,我国住宅价格对消费的影响整体上呈现微弱的财富效应,住宅价格的MPC位于0.0543到0.1155之间。2004年之前住宅价格上升对消费的影响波动剧烈,2004年后大致呈现先上升,2013年后开始下降的“倒U”型趋势。这说明近年来房价上升对消费的挤出效应迅速增强。鉴于此,从挤出效应传导机制入手,政府应该谨慎平稳调整房价、增加保障性住房供给,并提高城镇化进行中外来人口收入。     

Sharing the benefits of biodiversity the Kani TBGRI deal in Kerala,India

Abstract

The United Nations Convention on Biological Diversity (CBD) concluded at the Earth Summit in 1992, mandates that where utilisation of the knowledge, innovations and practices of local and indigenous communities leads to benefits, such benefits shall be equitably shared with the holders of such knowledge, innovations and practices. The study analyses some of the issues that have emerged in the context of a ‘benefit sharing exercise’ attempted by the Tropical Botanic Garden and Research Institute (TBGRI), a research institute based in Kerala, with the Kani tribals of Kerala, pursuant to the development of a pharmaceutical drug, based on the knowledge, information and natural resources that the Kanis have nurtured over many years.

As the case study illustrates, the debate on benefit sharing in the absence of other fundamental rights such as the rights to land, access to the resource and adequate governance structures becomes a limited and myopic exercise. A ‘fair and equitable benefit sharing mechanism’ would therefore call for certain basic pre‐conditions that will be discussed in the course of the study.     

Comment on Dennis P. Culhane et al.’s “public shelter admission rates in Philadelphia and New York City: The implications of turnover for sheltered population counts”

The article here extended reflects on the excessively narrow debate over the government-sponsored enterprises (GSEs)' cost-benefit transfer balance which had been raging for a quarter-century before the 2007–2009 financial crisis. That crisis has cast a new light on the actual costs of GSE operations and exposed the unsustainability of some of their benefits for homeownership. After injecting afew new findings into the traditional debate, this comment adds some of what has transpired in recent years and what may be inferred from it so far. Doing so brings additional analysis to bear on the article's conclusion that “the GSEs might not be justified” and “Maybe it is time for them to exit” although most politicians in the past have been disinclined to show them the door.     

The preservation needs of public housing

Abstract

The paper examines the preservation needs of public housing from the perspective of its physical condition and its ongoing repair and replacement needs. It begins by examining the range of needs that exist today, including the level of expenditures that would be required to put the stock in working order to meet existing codes, and to ensure the long‐term viability of the development. It then explores the level of expenditures that would be required on an ongoing basis to keep the stock in good repair and to meet future capital and preventive maintenance needs. The final section addresses several important policy issues, including overall funding requirements, the cost‐effectiveness of preservation efforts compared with vouchers and new construction, the special problems of troubled public housing authorities, and the need to establish stronger incentives for capital planning.     

Comment on Dennis P. Culhane et al.’s “Public shelter admission rates in Philadelphia and New York City: The implications of turnover for sheltered population counts”

Low-Income Housing Tax Credit (LIHTC) developments serve renter households with incomes between 30% and 60% of Area Median Family Income. Ideally, the program places units into neighborhoods where there is a shortage of units serving this cohort. LIHTC units are allocated to developers by state agencies through their Qualified Allocation Plans which should direct units to areas of need. Using a national database, this research examines where LIHTC developments were placed in service to determine whether these developments enter tracts experiencing shortages.

The LIHTC program is not directing units to those census tracts where there is a latent demand for units in this rent range. Rather, it is placing units into tracts that have surpluses. Equally, the program is not placing units in tracts with little or no affordable housing. This suggests that the program is not breaking down the income separation that exists in the nation's housing markets.     

The changing geography of metropolitan opportunity: The segregation of the poor in U.S. metropolitan areas, 1970 to 1990

Abstract

This analysis uses census tract data to measure the segregation of the poor in U.S. metropolitan areas in 1970, 1980, and 1990. Two measures of segregation are used: the indices of dissimilarity and isolation.

In 1990 the mean dissimilarity of the poor in the 100 largest U.S. metropolitan areas was 36.1, which is substantial but below the 60.6 dissimilarity of blacks. The 1990 isolation of the poor was 21.0. From 1970 to 1990, the dissimilarity of the poor increased by 11 percent, and the isolation of the poor rose by 9 percent; in contrast, racial segregation declined. Exploratory regression analyses reveal that income segregation in metropolitan areas was significantly greater in 1990 and increased more from 1970 to 1990 in the Northeast than in the South and West. Midwest areas generally were not significantly different from Northeast areas in 1990 segregation levels or in changes from 1970 to 1990.     

From dependency to self‐sufficiency: An appraisal of the gateway transitional families program

Abstract

This article presents a longitudinal evaluation of the Gateway Transitional Families Program, an innovative self‐sufficiency program designed to help public housing residents leave public housing for their own homes. The evaluation followed participants and a comparison group over six years to isolate program impacts on employment and receipt of Aid to Families with Dependent Children (AFDC), food stamps, and housing assistance.

Many participants dropped out of the program. Difficulty in juggling educational and child‐rearing responsibilities, noncompliance with program or public housing regulations, low wages while in the program, impatience with the length of the program, and staff shortages and turnover contributed to the dropout rate. Those who finished the program experienced modest increases in income, decreases in receipt of AFDC and food stamps, and reduced reliance on housing assistance relative to comparison group members. Furthermore, graduates were more likely than comparison group members to have bought a home.     

Neighborhood change and the city of New York's ten‐year housing plan

Abstract

This article examines neighborhood changes associated with New York City's Ten‐Year Plan—the largest municipal housing program in the United States. We examine indicators of change, in the context of two possible hypotheses about the program's impact: (1) neighborhood revitalization, including improved physical and housing market conditions, as well as gentrification, and (2) the concentration of poor and welfare‐dependent households, as well as the possibility of residential segregation by race or ethnicity.

Our results present a mixed picture, with some evidence favoring both hypotheses, especially when parts of the city, particularly the South Bronx, are examined separately. Specifically, the program is associated with steep declines in the rate of boarded‐up buildings and some indications of increased home values, as well as rent burdens. However, it is also correlated with increases in maintenance deficiencies and a greater proportion of poor, single‐parent, and welfare‐dependent households, but there is little evidence of accentuated residential segregation.