What STIRPAT tells about effects of population and affluence on the environment?

In the literature on the application of STIRPAT to environmental impacts of population and affluence, the parameter estimates differ from study to study. One example is the effect of population size on CO₂ emissions, which is concluded to be very close to 1 in some studies (e.g., York et al., 2003) while far from 1 in others (e.g., Shi, 2003). What can explain these differences in results? In the present paper, I offer an alternative model equivalent to STIRPAT, which explicitly specifies the different role of technology (T) in STIRPAT from IPAT. By the alternative model, I conclude that different functional forms of STIRPAT can be one explanation for the difference among estimates in the studies on environmental impacts of population and affluence. The alternative model can also help to determine which factors to be added in STIRPAT.     

Ecological footprint accounting in the life cycle assessment of products

We present and discuss ecological footprint (EF) calculations for a large number of products and services consumed in the western economy. Product-specific EFs were calculated from consistent and quality-controlled life cycle information of 2630 products and services, including energy, materials, transport, waste treatment and infrastructural processes. We formed 19 homogeneous product/process subgroups for further analysis, containing in total 1549 processes. Per group, the average contribution of two types of land occupation (direct and energy related) to the total EF was derived. It was found that the ecological footprint of the majority of products is dominated by the consumption of non-renewable energy. Notable exceptions are the EFs of biomass energy, hydro energy, paper and cardboard, and agricultural products with a relatively high contribution of direct land occupation. We also compared the ecological footprint results with the results of a commonly used life cycle impact assessment method, the Ecoindicator 99 (EI). It was found that the majority of the products have an EF/EI ratio of around 30 m²-eq. yr/ecopoint ± a factor of 5. The typical ratio reduces to 25 m² yr/ecopoints by excluding the arbitrary EF for nuclear energy demand. The relatively small variation of this ratio implies that the use of land and use of fossil fuels are important drivers of overall environmental impact. Ecological footprints may therefore serve as a screening indicator for environmental performance. However, our results also show that the usefulness of EF as a stand-alone indicator for environmental impact is limited for product life cycles with relative high mineral consumption and process-specific metal and dust emissions. For these products the EF/EI ratio can substantially deviate from the average value. Finally, we suggest that the ecological footprint product data provided in this paper can be used to improve the footprint estimates of production, import and export of products on a national scale and footprint estimates of various lifestyles.     

Evaluating the effects of embodied energy in international trade on ecological footprint in China

Based on sub-sectoral level of economy and detailed traded items, embodied energy (EE) in international trade flow in China is estimated during 1996-2004, and the effects of EE on sustainability are quantified by using one of the most popular indicators—Ecological footprint (EF). A framework of EF method, which is more relevant to realism of specific country, is proposed in this paper. The results show that China is a net importer of EE during the period covered by this study except for the year from 1997 to 1999. Imported, Exported and Net imported EE tends to increase sharply along time series. Net imported energy would increase 38% and energy consumption would increase 2.8% in 2004 if EE were taken into account. Footprint_energy is the most important part of EF components and is significantly affected by EE, and the effects of EE on EF are similar to that of Footprint_energy. Footprint_energy, EF and ecological deficit of 2004 will be underestimated about 2.92%, 1.36%, 2.83%, res pectively, if EE is not taken into the national energy budget. Continuous increase of EF and ecological deficit along time series indicates that China is moving away from sustainability. 1.47 times Chinese territories are accurately occupied by China in 1996 while 1.71 times in 2004. Obviously unsustainability procedure of China is accelerated by EE. The contribution of EE to EF and ecological deficit is small in absolute terms expressed in per capita, but the effects on whole nation are huge if the population of China multiplies them. To curb the increase of EF and ecological deficit and to achieve the goal of sustainability, some policy and measures are also proposed.     

A note on the fundamental theorem of exact aggregation

If individual i's demands for a commodity are a function of prices, p, income M_i and a vector of attributes A_i, then aggregate demand is

This paper derives the necessary and sufficient conditions of f_i, F and a system of functions g_k(M₁,…,M_N,A₁,…,A_N) symmetric in the M's and A's such that F can be written in the form F(p, g, (M₁,…,M_n,A₁,…,A_N),…, g_n(M₁,…,M_n,A₁,… ,A_n)) for all values of its arguments.     

中国区域碳排放空间计量研究

如何从空间视角实现经济发展与碳减排双赢,是建设“美国中国”的重要推手,也是生态文明建设的必然要求。基于STIRPAT模型,从区域层面构建碳排放驱动因素扩展STIRPAT模型,并运用空间杜宾模型实证考察各驱动因素对碳排放规模和碳排放强度的影响。结果显示：地区间碳排放存在显著的示范和带头作用,驱动因素通过直接和间接途径影响碳排放,除能源价格外,其他影响因素均表现出显著性。因此,实现碳减排需要充分考虑空间相关性、异质性和外溢性,稳步推进城镇化进程,加大技术创新步伐,优化产业结构升级和能源消费结构,适度提高能源价格,在扩大对外开放的同时加大对外商投资的甄别。     

Lifestyles, technology and CO2 emissions in China: A regional comparative analysis

With rapid economic development, higher income levels, urbanization and other socio-economic drivers, people's lifestyles in China have changed remarkably over the last 50 years. This paper uses the IPAT model (where I = Impact representing CO₂ emissions, P = Population, A = Affluence, and T = emission intensity) to analyze how these main drivers contributed to the growth of CO₂ emissions over this time period. Affluence or lifestyle change has been variously recognized as one of the key factors contributing to CO₂ emissions. Through comparative analysis of the development of five regions in China, we trace lifestyle changes since the foundation of the People's Republic of China (PRC) in 1949 until 2002. We find that household consumption across the five regions follows similar trajectories, driven by changes in income and the increasing availability of goods and services, although significant differences still exist between and within regions due to differential policies in China and different possibilities for social mobility. There are considerable differences between the southeast and northwest and between urban and rural areas. We also found that technological improvements have not been able to fully compensate for the increase of emissions due to population growth and increasing wealth, which is also in line with results from other studies. Finally, this paper emphasizes that developing countries such as China, which is home to 22% of the world population and a growing middle class, and which is on a fast track to modernization, need to ensure that people's lifestyles are changing towards more sustainable ways of living. China has been investing heavily in infrastructure and thus creating the emissions of tomorrow. Thus investing, for example, in public transport and low energy building today will help reduce emissions in the future and will support more sustainable lifestyles.     

A comparison of preferences for two GLP-1 products – liraglutide and exenatide – for the treatment of type 2 diabetes

Abstract

Objective:

To use time trade-off (TTO) to compare patient preferences for profiles of two glucagon-like peptide (GLP-1) products for the treatment of type 2 diabetes (liraglutide and exenatide) that vary on four key attributes – efficacy (as measured by hemoglobin A_1C), incidence of nausea, incidence of hypoglycemia, and dosing frequency (QD vs. BID) – and measure the contribution of those attributes to preferences.

Methods:

A total of 382 people with T2DM were recruited to participate in an internet-based survey consisting of a series of health-related questions, a conjoint exercise and a set of time trade-off items. In the conjoint exercise, respondents were presented with eight pairs of hypothetical GLP-1 profiles, and completed a time-tradeoff exercise for each pair.

Results:

The product profile representing liraglutide was preferred by 96% of respondents and resulted in significantly higher health utilities (0.038) than the product profile representing exenatide (0.978 vs. 0.94, p?<?0.05). Estimated preference scores from the conjoint analysis revealed that efficacy measured by hemoglobin A_1C is the most important attribute, followed by nausea, hypoglycemia, and dosing schedule.

Limitations:

On-line participants may not represent ‘typical’ type 2 diabetes patients, and brief product profiles represented results from clinical trials, not clinical practice

Conclusion:

Based on the four attributes presented, patients prefer liraglutide over exenatide. Preference is based on superior efficacy and less nausea more than less hypoglycemia and once-daily dosing.     

Knowledge of African countries: production and value of doctoral dissertations

The notion that lack of knowledge undermines the economic performance of African countries is deeply and widely held to be true. Yet quantitative evidence for the basis of that truth is few and far in-between. This article first describes a conventional production function approach to the creation of knowledge of African countries in terms of a relative and indirect measure of the quantity of dissertations (D). Second, it assesses the imputed values of knowledge. In the first instance it finds that relative income (Y), population (N), openness (Z), and technical factors (A) are central to the production of knowledge of African countries. In the second instance, the imputed values of knowledge are positive, but of modest magnitude. The results recommend more investment in the production of knowledge of African countries, improved openness, and especially reduced opportunity cost of knowledge creation which now differs widely across countries, and averages 10.7%. For further research the results suggest that dissertations may be useful proxies for human capital in economic growth regressions.     

Non-causality: The role of the omitted variables

In this paper a proof is offered that if a variable Y₃ does not cause a variable Y₁ in the bivariate system (Y₁, Y₃) and Y₃ causes a variable Y₁ in higher-order system (Y₁, Y₂, Y₃), then the omitted variable Y₂ must cause the variable Y₁ in the bivariate system (Y₁, Y₂) and in the trivariate system (Y₁, Y₂, Y₃).     

Numerical Computation of Equilibrium Bid Functions in a First-Price Auction with Heterogeneous Risk Attitudes

We use numerical methods to compute Nash equilibrium (NE) bid functions for four agents bidding in a first-price auction. Each bidderi is randomly assigned:r _i [0,r _max], where 1 –r _i is the Arrow-Pratt measure of constant relative risk aversion. Eachr _i is independently drawn from the cumulative distribution function (·), a beta distribution on [0,r _max]. For various values of the maximum propensity to seek risk,r _max, the expected value of any bidder's risk characteristic,E (r _i ), and the probability that any bidder is risk seeking,P (r _i > 1), we determine the nonlinear characteristics of the (NE) bid functions.     

黄河水资源与河南经济生态发展研究

水是人民生活和经济社会的基础性战略资源,是生态环境的控制要素。黄河水资源作为河南省最大的过境水资源,是河南省未来经济发展的重要支撑资源,也是河南省率先实现中原崛起提供比较优势所在。充分利用黄河水资源,构建黄河供水网,是解决沿黄地区水资源瓶颈,促进河南经济生态发展的关键所在。为此,应把引黄供水、构建黄河水网放在更加重要的战略位置,提高现有黄河水网质量,进一步拓宽黄河水资源利用空间,形成河南全省范围内的黄河水资源网。     

Why it Pays to Conceal: On the Optimal Timing of Acquiring Verifiable Information

Abstract. We consider optimal contracts when a principal has two sources to detect bad projects. The first one is an information technology without agency costs (IT_P), whereas the second one is the expertise of an agent subject to moral hazard, adverse selection and limited liability (IT_A). First, we show that the principal does not necessarily benefit from access to additional information and thereby may prefer to ignore it. Second, we discuss different timings of information release, i.e., a disclosure contract offered to the agent after the principal announced the result of IT_P , and a concealment contract where the agent exerts effort before IT_P is checked. We find that concealment is superior whenever the quality of IT_P is sufficiently low. Then, IT_P is almost worthless under a disclosure contract, while it can still be exploited to reduce the agent's information rent under concealment. If the quality of IT_P improves, disclosure can be superior as it allows to adjust the agent's effort to the updated expected quality of the project. However, even for a highly informative IT_P , concealment can be superior as it mitigates the adverse selection problem.     

黄河流域绿色水资源利用率与经济高质量发展耦合研究——以河南省为例

黄河流域生态保护和高质量发展已成为国家战略,这对黄河流域生态保护和经济发展来说意义非凡,为黄河流域各省份高质量发展带来了机会。河南是中部大省,位于黄河的中下游,以河南省为例,构建综合评价指标体系,运用熵值法对河南省绿色水资源利用率和经济高质量发展水平作出综合评价,并构建耦合协调模型,分析研究2013—2018年黄河流域经济高质量发展与绿色水资源利用率耦合协调程度。结果表明,2013—2018年河南省绿色水资源利用率不断提高,经济高质量发展水平呈逐步上升趋势,但是两者之间并非一直同步发展;绿色水资源利用率与经济高质量发展耦合协调程度逐步提高,经历了从严重失调—勉强协调—初级协调—中级协调—优质协调五个发展阶段。     

Modelling the propagation of adult male muscle dysmorphia in Spain: economic,emotional and social drivers

Males aged over 40 do more gym practice to improve their body image as a way of reinforcing their personal self-esteem and sexual appeal. Cases when self-image becomes an obsession may result in a body dysmorphic disorder named ‘muscle dysmorphia’ (MD). The combination of psychological, environmental and biological drivers determines the appearance and development of this disorder. In this article, we developed a discrete population mathematical model to forecast the rate of prevalence of males who are noncompetitive bodybuilders at risk of suffering MD in Spain in forthcoming years. Economic, emotional, sociological and psychological motivations were taken into account to quantify the dynamic behaviour of Spanish noncompetitive bodybuilders. The impact of the unemployment is reflected in the construction of two coefficients, α_u and α₂₁, which explain subpopulation transits due to the economy. Sociological influences, such as human herding and social propagation, were also considered. Our results predict an increase in Spanish noncompetitive bodybuilders suffering MD from 1% in 2011 to around 11% in 2015. Our model can be applied to any other western country where data are available and to another study period when the hypotheses are applicable.     

Remarks on the application of statistical games to technological development forecasting

This work presents the probability of determining a quantitative forecast of technological development S(t) defined by a set m of parameters S⁽¹⁾(t),S⁽²⁾(t),…,S^(m)(t), based on statistical game theory. Assuming that the coordinates S⁽ⁱ⁾(t) (i = 1, 2,…,m) of a forecasted vector S(t) are stochastic processes with given probabilistic characteristics, a formula of a function forecasting the value of a coordinate S⁽ⁱ⁾(t) of this vector can be obtained. This formula permits to determine a vector of forecasts _τT(x) of technological development S(t) at a given moment t = τ+T.     

Impact of FDI and trade on environmental quality in the CAFTA-DR region

This study investigates the relationship between foreign direct investment (FDI), trade and industrial emissions in member countries of the Central American Free Trade Agreement–Dominican Republic (CAFTA-DR) between 1979 and 2010. Our model is based on extant literature about the Environmental Kuznets’ Curve framework. In this study, we consider sulphur dioxide (SO₂), nitrogen oxides (NO_x) and carbon dioxide (CO₂) as our dependent variables. Our key independent variables are FDI and trade. Our study finds evidence that foreign investment and trade have had a negative impact on our selected emissions. However, our models also estimate turning points which are below the current GDP per capita values for all CAFTA-DR member countries. This is an encouraging trend in terms of the potential reduction in emissions in the region.     

Main Currents of Marxism

We present a three-fold test for sustainability on policies addressing environmental and natural resource management. The first — ecological holism — requires that management of natural systems not only ensure the long term viability of ecosystem functions and enhanced diversity of wildlife within that ecosystem, but also facilitate the provision of renewable energy and material resources. The second — community centeredness — is an assessment of the improvement (or reduction) in economic wellbeing of local populations measured by employment and income and in quality of life for the larger community resulting from that policy. The third — institutional legitimacy — evaluates the level of justice that a policy and its outcome(s) bring to the entire community (here, just policies will satisfy Rawls's "veil of ignorance" test). Three policies for National Forest management on Washington's Olympic Peninsula are examined and results are compared: the Northwest Forest Plan, the Wild Olympics Wilderness and Scenic Rivers Act of 2012 (Wild Olympics), and The Third Way (an alternative forest management option). Each policy satisfies the first test of ecological holism, but not in equal measures. Success in this regard can be differentially ranked because the relative impacts are not neutral. Both the Northwest Forest Plan and Wild Olympics fail the test of community centeredness. In contrast, The Third Way promotes community centeredness and ecological holism. We assert that, as a result, it would satisfy John Rawls's test for justice, and it is institutionally legitimate.     

Regression analysis on the variation in efficiency frontiers for prevention stage of HIV/AIDS

Abstract

Objectives:

To investigate how the cost effectiveness of preventing HIV/AIDS varies across possible efficiency frontiers (EFs) by taking into account potentially relevant external factors, such as prevention stage, and how the EFs can be characterized using regression analysis given uncertainty of the QALY-cost estimates.

Methods:

We reviewed cost-effectiveness estimates for the prevention and treatment of HIV/AIDS published from 2002–2007 and catalogued in the Tufts Medical Center Cost-Effectiveness Analysis (CEA) Registry. We constructed efficiency frontier (EF) curves by plotting QALYs against costs, using methods used by the Institute for Quality and Efficiency in Health Care (IQWiG) in Germany. We stratified the QALY-cost ratios by prevention stage, country of study, and payer perspective, and estimated EF equations using log and square-root models.

Results:

A total of 53 QALY-cost ratios were identified for HIV/AIDS in the Tufts CEA Registry. Plotted ratios stratified by prevention stage were visually grouped into a cluster consisting of primary/secondary prevention measures and a cluster consisting of tertiary measures. Correlation coefficients for each cluster were statistically significant. For each cluster, we derived two EF equations – one based on the log model, and one based on the square-root model.

Discussion:

Our findings indicate that stratification of HIV/AIDS interventions by prevention stage can yield distinct EFs, and that the correlation and regression analyses are useful for parametrically characterizing EF equations. Our study has certain limitations, such as the small number of included articles and the potential for study populations to be non-representative of countries of interest. Nonetheless, our approach could help develop a deeper appreciation of cost effectiveness beyond the deterministic approach developed by IQWiG.     

Incorporating methane into ecological footprint analysis: A case study of Ireland

Carbon dioxide (CO₂) accounting is important to global ecological footprint analysis. However methane (CH₄), with a global warming potential (GWP) 25 times that of CO₂, should not be neglected as an environmental indicator for informed environmental management. While this is a significant component, the CH₄ associated with imported embodied energy should also be included in national greenhouse gas (GHG) inventories. This study proposes an initial method for incorporating methane into ecological footprint analyses and hopes to inform future debate on its inclusion. In order to account for differences in methane intensities from exporting countries, methane intensities for OECD countries were calculated using emission and energy consumption estimates taken directly from National Inventory Reports (NIR), published in conjunction with the Intergovernmental Panel on Climate Change (IPCC). For other countries the methane intensities were estimated using energy balances published by the International Energy Association (IEA) and IPCC default emission factors. In order to estimate embodied organic methane, material imports and exports were translated into units (such as live animals) capable of conversion into methane emissions. A significant increase in Ireland's footprint results from the inclusion of the GWP of methane is included within the footprint calculation.     

Exploring past and future changes in the ecological footprint for world regions

The Ecological Footprint (EF) has received considerable attention as a useful indicator in the context of sustainable development. So far, it has mostly been applied as a static indicator. Here, we have derived a set of long-term EF scenarios for 17 world regions using the IMAGE 2.2 implementation of the IPCCs SRES scenarios. The scenarios are used to discuss potential trends in EFs in different world regions but also to analyse underlying trends driving changes in the EF. The baseline scenarios show the EF for real land use only (not accounting for CO₂) to increase further in the next few decades in most world regions, being driven by population growth, changes in human diets towards more land-intensive products and overall increases in consumption levels. Future crop yield improvements and technology development will partly offset these trends, resulting in decreasing per capita EFs, but increasing total EFs. In the longer term, EF development may strongly diverge on the basis of assumptions made in the different baseline scenarios (from 5.4 Gha at present to 6.0–8.2 Gha in 2050 depending on the scenario). The aggregated EF following the definition of Wackernagel et al. (Proc. Natl. Acad. Sci. 99 (2002) 9266–9271) (including virtual land for CO₂) increases more strongly, from 12.6 to 20–31 Gha depending on the different scenarios. An alternative scenario was developed to explore whether optimistic assumptions for changes in consumption and production patterns could limit the increase of the global EF, which limited EF increase to 15 Gha in 2050. This scenario still allowed for population growth and strong economic development in low-income regions.