Effects of permitted effluent limits on environmental compliance levels

This paper empirically analyzes the effects of permitted effluent limits on compliance levels - discharges relative to limits - at individual polluting facilities. In particular, it constructs and employs effluent limit-related regressors that measure the differences between the actual effluent limit level imposed on a particular facility for a given month and three benchmarks: federally-mandated standard for effluent limit level, a particular facility's average effluent limit level over a specified period (e.g., entire sample period), and preceding monthly limit at a particular facility (i.e., transition to new limit). By examining the effects of effluent limit levels as measured relative to these three benchmarks, this paper explores whether limit stringency affects compliance level choices (e.g., more stringent limits undermine compliance), whether adjustments to treatment are non-smooth (“lumpy”), and whether quick adjustments are difficult. Evidence of these possibilities would have meaningful implications for environmental protection policies.     

滇池治污要退耕还湖

滇池治污忽视了天然湿地的净化潮水作用,存在重大缺陷：没有从根本上查清污染原因,《滇池保护条例》中有一些观点须重新审视,滇池功能的认识和定位有重大缺陷。作者从云南建设绿色经济强省和昆明建设绿色生态旅游城市出发,以生态恢复和环境治理为切入点,提出退耕还湖等几点建议。     

含油污水的生化处理工艺

油田在开采原油及油气处理过程中,伴生有大量含油污水,处理不好,不仅污染环境,而且浪费资源;处理得当,则节能又环保。因此,含油污水的处理对于保护水资源、维持生态平衡和促进经济发展都有重要的意义。在众多的处理技术工艺之中,生化处理工艺逐渐显示出它独特的优势。     

中国城市污水处理设施市场化改革路径研究

城市污水处理市场化改革的政策设计应坚持“厂网分开”的原则,城市排水管网的建设投资仍由政府承担,但管网的运营可以委托专业公司进行市场化运营;城市污水处理厂的建设、运营应全面引入社会资本进行系统的市场化设计。     

A network meta-analysis to compare simeprevir with boceprevir and telaprevir in combination with peginterferon-α and ribavirin in patients infected with genotype 1 Hepatitis C virus

Abstract

Objective:

To conduct a network meta-analysis (NMA) to assess the relative efficacy and safety of simeprevir, a second generation oral protease inhibitor (PI), compared to telaprevir and boceprevir in combination with pegylated interferon-α and ribavirin (PR) in patients with chronic hepatitis C.     

Antiepileptic drug treatment patterns and economic burden of commercially-insured patients with refractory epilepsy with partial onset seizures in the United States

Abstract

Objective:

To assess the economic burden in direct healthcare utilization and costs for refractory epileptic patients with partial onset seizures (POS) and assess the antiepileptic drug (AED) treatment patterns among these patients.     

Treatment effects in sample selection models and their nonparametric estimation

In a sample-selection model with the ‘selection’ variable Q$Q$ and the ‘outcome’ variable Y^∗$Y^{\ast }$, Y^∗$Y^{\ast }$ is observed only when Q=1$Q=1$. For a treatment D$D$ affecting both Q$Q$ and Y^∗$Y^{\ast }$, three effects are of interest: ‘participation  ’ (i.e., the selection) effect of D$D$ on Q$Q$, ‘visible performance  ’ (i.e., the observed outcome) effect of D$D$ on Y≡QY^∗$Y\equiv Q{Y}^{\ast }$, and ‘invisible performance  ’ (i.e., the latent outcome) effect of D$D$ on Y^∗$Y^{\ast }$. This paper shows the conditions under which the three effects are identified, respectively, by the three corresponding mean differences of Q$Q$, Y$Y$, and Y|Q=1$Y|Q=1$ (i.e., Y^∗|Q=1$Y^{\ast }|Q=1$) across the control (D=0$D=0$) and treatment (D=1$D=1$) groups. Our nonparametric estimators for those effects adopt a two-sample framework and have several advantages over the usual matching methods. First, there is no need to select the number of matched observations. Second, the asymptotic distribution is easily obtained. Third, over-sampling the control/treatment group is allowed. Fourth, there is a built-in mechanism that takes into account the ‘non-overlapping support problem’, which the usual matching deals with by choosing a ‘caliper’. Fifth, a sensitivity analysis to gauge the presence of unobserved confounders is available. A simulation study is conducted to compare the proposed methods with matching methods, and a real data illustration is provided.     

在华外资银行的“国民待遇”

我国政府为了履行加入世贸承诺,对在华外资银行实行"国民待遇"原则,逐渐开放本国银行市场。但是在我国现阶段的国情背景下,该原则仍呈现灵活机动的状态。在如此政策背景和市场压力下,在华外资银行面临着诸多机遇与挑战。