区域产业发展视角的农业综合开发影响评估——基于对蔬菜产业的干预效应分析

【目的】通过定量方法准确评估农业综合开发对区域优势产业发展的影响有重要意义。【方法】从农业综合开发对蔬菜产业的项目干预效应入手,以县级为单位,将当年农业综合开发项目扶持内容包括蔬菜产业的县级单位划分为干预组,其他为控制组。采用可以有效解决样品选择偏差的倾向得分匹配方法,通过引入协变量、平衡检验、匹配等步骤,在控制组中找到与干预组成员单位特征相似的成员,构建反事实研究框架。【结果】结果得出,项目干预组比控制组区域的蔬菜播种面积占比高出1~3个百分点,说明农业综合开发项目对蔬菜产业的扶持对蔬菜播种面积的扩大有促进作用,利于蔬菜产业壮大。通过协变量影响力分析得出,地区的蔬菜生产优势是最重要的影响因素,从侧面证明了农业综合开发项目的扶持方向紧跟区域优势的政策宗旨。【结论】可见,通过有方向性的农业综合开发项目实施扶持特定产业对促进区域优势产业发展和实现农业结构优化是有效的。     

On estimating long-run effects in models with lagged dependent variables

A common procedure in economics is to estimate long-run effects from models with lagged dependent variables. For example, macro panel studies frequently are concerned with estimating the long-run impacts of fiscal policy, international aid, or foreign investment.Our analysis points out the hazards of this practice. We use Monte Carlo experiments to demonstrate that estimating long-run impacts from dynamic models produces unreliable results.Biases can be substantial, sample ranges very wide, and hypothesis tests can be rendered useless in realistic data environments. There are three reasons for this poor performance. First, OLS estimates of the coefficient of a lagged dependent variable are downwardly biased in finite samples. Second, small biases in the estimate of the lagged, dependent variable coefficient are magnified in the calculation of long-run effects. And third, and perhaps most importantly, the statistical distribution associated with estimates of the LRP is complicated, heavy-tailed, and difficult to use for hypothesis testing. While many of the underlying problems have been long-known in the literature, the continued widespread use of the associated empirical procedures suggests that researchers are unaware of the extent and severity of the estimation problems. This study aims to illustrate their practical importance for applied research.     

Heterogeneous returns to chemical fertilizer at the intensive margins: Insights from Nepal

Increased fertilizer use is considered important for agricultural development in low-income countries. Promoting increased use of chemical fertilizer by lowering its price may be ineffective if demand is price inelastic. In theory, the price elasticity of demand depends on the returns to its use, but the evidence is scarce. Furthermore, while returns are often estimated for small changes in chemical fertilizer use, returns to larger changes in its use (intensive margins) are less understood. Through the inter-zonal comparisons in Nepal, we provide indicative evidence that greater returns to chemical fertilizer are associated with greater price elasticities of demand. Moreover, the evidence suggests that returns at the intensive margins, rather than returns to small changes, may largely account for inter-zonal differences in returns to chemical fertilizer within Nepal. The results suggest that better understanding the returns at the intensive margins is critical for effective agricultural inputs policies in developing countries.     

The effects of exports on facility environmental performance: Evidence from a matching approach

This paper employs matching techniques to investigate the effects of facility export status on environmental performance. Using facility-level criteria air emission data in the US manufacturing industry, we find the industry-specific effects of export status on emission intensity, measured by emissions per value of sale. In some industries, there is consistent and robust evidence supporting the superior environmental performance of exporters relative to non-exporters in terms of emission intensity for all criteria air pollutants tracked. In other industries, we find weak evidence that exporters appear to have a higher emission intensity than non-exporters. This industrial heterogeneity in the effects of exporting on the environment is closely related to industrial characteristics including pollution abatement capital expenditure, trade costs, capital intensity and others.     

Economic evaluation of human urinary kallindinogenase for patients with acute ischemic stroke in China

Objectives: In China, both human urinary kallindinogenase (HUK) and 3-n-butylphthalide (NBP) are recommended for clinical use to improve cerebral blood circulation during an acute ischemic stroke (AIS). The objective was to evaluate the economic value of HUK vs NBP for patients with AIS from a Chinese payer’s perspective.

Methods: An economic evaluation based on data of patients who have been treated with either HUK (n?=?488) or NBP (n?=?885) from a prospective, phase IV, multi-center, clinical registry study (Chinese Acute Ischemic Stroke Treatment Outcome Registry, CASTOR) was conducted to analyze the cost and effectiveness of HUK vs NBP for AIS in China. Before the analysis, the patients were matched using propensity score. Both a cost-minimization analysis and a cost-effectiveness analysis were conducted to compare the matched pairs. A bootstrapping exercise was conducted for the matched arms to demonstrate the probability of one intervention being cost-effective over another for a given willingness-to-pay for an extra quality-adjusted life-year (QALY).

Results: After propensity score matching, 463 pairs were matched. The overall medical cost in the HUK arm is USD 2,701.20, while the NBP arm is USD 3,436.83, indicating HUK is preferred with cost-minimization analysis. Although the QALY gained in the HUK arm (0.77176) compared with the NBP arm (0.76831) is statistically insignificant (p?=?.4862), the cost-effectiveness analysis as exploratory analysis found that, compared with NBP, HUK is a cost-saving strategy with the lower costs of USD 735.63 and greater QALYs gained of 0.00345. Among the 5,000 bootstrapping replications, 100% indicates that HUK is cost-effective compared with NBP under a 1-time-GDP threshold; and 97.12% indicates the same under a 3-time-GDP threshold.

Conclusion: This economic evaluation study indicates that administrating HUK is a cost-saving therapy compared with NBP for managing blood flow during AIS in the Chinese setting.     

Measuring the effects of preservation on farm profits in a continuous treatment setting

Despite billions of dollars of public appropriations to state purchase of development rights (PDR) programmes, there has been limited evaluation of the effects of these investments on the economic performance of preserved farms. This article estimates dose-response functions to evaluate the effects of enrolment in New Jersey’s PDR programme on farm profitability. The generalized propensity score method in a continuous treatment setting is used to address selection bias arising from voluntary programme participation. Treatment effects are measured across treatment levels to determine whether farm profitability is affected differently across levels of programme participation. Our findings reveal that, relative to unpreserved farms, profit per acre tends to increase along lower treatment levels. The profit per acre of preserved farms in the 1–40% treatment range is, on average, $407 higher than that of unpreserved farms in the full sample. Positive profit differentials averaging between $317 and $472 per acre are also observed in the 1–20%, 1–40% and 1–60% treatment quintiles in the farming occupation sample. We do not observe statistically significant profitability differentials when treatment effects are averaged across all positive treatment values.     

Self-determination and risk: the role of life goals and causality orientation in domain-specific risk propensity

A growing body of risk research shows that risk is content specific. Accordingly, various studies have highlighted some factors that could explain why people’s risk propensity may arise in certain domains of risk (e.g. the financial domain) but not in other domains (e.g. the recreational domain). Until now, no research has examined motivation as a possible correlate of domain-specific risk propensity. On the basis of self-determination theory (SDT), we examined the role of both extrinsic life goals (i.e. superficial goal striving, including fame, money, and physical attraction) and control-orientated personality style (i.e. feeling that one’s behaviors are governed by external contingencies) in the propensity to take risks in various domains (social, ethical, recreational, financial, and health/safety). A community sample of 197 participants completed measures scaled to assess extrinsic life goals, controlled orientation, and domain-specific propensity (DOSPERT). The results showed that pursuing extrinsic goals and being control oriented increased the propensity to take ethical, recreational, financial, and health/safety risks but decreased the propensity to take social risks. In addition, to corroborate that risk propensity is domain specific, these results indicate that superficial life aspiration and sensitivity to social pressures are highly predictive of instrumental risks (e.g. ethical and financial), moderately predictive of health risks, and negatively predictive of ego-threatening risks (e.g. social risk). The results are discussed in light of the domain-specific risk literature and in the perspective of interventions based on SDT.     

老年协会参与对老年虐待的影响

本文基于第三期全国妇女社会地位调查老年专项调查数据, 使用倾向值分析和工具变量方法,研究老年协会参与对老年虐待的影响及其作用机制。研究发现老年协会参与能有效抑制老年虐待。从作用机制来看,老年人在家庭私人生活领域之外的社会参与程度越高,参加文娱活动、志愿服务、互帮互惠等社会交往活动越频繁,法律意识越强,遭受家庭成员虐待的风险越小。但是目前广大老年人群特别是非精英的普通弱势老年人参加各类社会组织的积极性和广泛性还不够。对此,政府有关部门应强化城乡基层老年社会组织建设,为广大老年群体尤其是普通老人积极参与创造条件。针对家庭赡养中的虐老问题,老年社会组织应从法律、社会治理等方面开展鉴别、预防和干预工作,提升老年人法律素养,实施家庭支持策略强化延续家庭养老功能,维护弱势老年人合法权益。     

Do German Welfare‐to‐Work Programmes Reduce Welfare Dependency and Increase Employment?

Abstract. During the last decade, many Western economies reformed their welfare systems with the aim of activating welfare recipients by increasing welfare‐to‐work programmes (WTWP) and job‐search enforcement. We evaluate the short‐term effects of three important German WTWP implemented after a major reform in January 2005 (‘Hartz IV’), namely short training, further training with a planned duration of up to three months and public workfare programmes (‘One‐Euro‐Jobs’). Our analysis is based on a combination of a large‐scale survey and administrative data that is rich with respect to individual, household, agency level and regional information. We use this richness of the data to base the econometric evaluation on a selection‐on‐observables approach. We find that short‐term training programmes, on average, increase their participants' employment perspectives. There is also considerable effect heterogeneity across different subgroups of participants that could be exploited to improve the allocation of welfare recipients to the specific programmes and thus increase overall programme effectiveness.     

农村居民消费结构变动的时序分析——以河北省为例

基于中国经济增长模式正在向消费主导型转变,以农村居民的生活消费作为研究重点,选择河北省作为研究区域,通过1993～2008年的时间序列数据对该区域农村居民的消费结构进行统计分析,意图探寻在相对发达的农村地区如何进一步优化农村消费结构,找到扩大农村消费市场的有效途径,从而促进经济的协调发展,为新农村的建设提供政策建议。