Quantifying uncertainty in the biospheric carbon flux for England and Wales

Summary.  A crucial issue in the current global warming debate is the effect of vegetation and soils on carbon dioxide (CO₂) concentrations in the atmosphere. Vegetation can extract CO₂ through photosynthesis, but respiration, decay of soil organic matter and disturbance effects such as fire return it to the atmosphere. The balance of these processes is the net carbon flux. To estimate the biospheric carbon flux for England and Wales, we address the statistical problem of inference for the sum of multiple outputs from a complex deterministic computer code whose input parameters are uncertain. The code is a process model which simulates the carbon dynamics of vegetation and soils, including the amount of carbon that is stored as a result of photosynthesis and the amount that is returned to the atmosphere through respiration. The aggregation of outputs corresponding to multiple sites and types of vegetation in a region gives an estimate of the total carbon flux for that region over a period of time. Expert prior opinions are elicited for marginal uncertainty about the relevant input parameters and for correlations of inputs between sites. A Gaussian process model is used to build emulators of the multiple code outputs and Bayesian uncertainty analysis is then used to propagate uncertainty in the input parameters through to uncertainty on the aggregated output. Numerical results are presented for England and Wales in the year 2000. It is estimated that vegetation and soils in England and Wales constituted a net sink of 7.55 Mt C (1 Mt C = 10¹² g of carbon) in 2000, with standard deviation 0.56 Mt C resulting from the sources of uncertainty that are considered.     

国外生态税实践及其对我国可持续发展建设的启示

初步探讨了生态税在可持续发展中的作用,认为对于正在实施可持续发展战略的中国来说,课征生态税是实现这个战略的重要手段。     

Work performance and tax compliance in flat and progressive tax systems

Different tax systems, and their impact on work motivation and tax compliance are significant issues in contemporary political and economic debates. The proportional feature of a flat tax system is assumed to lead to higher performance, while the fairness of the redistributive progressive tax system is assumed to result in higher tax compliance. However, empirical findings on the topic are inconclusive. Both work performance and tax compliance under different tax systems were examined in an experiment, with special attention devoted to the effect of a change in tax systems. A flat tax system was supposed to induce greater work performance, whereas a progressive tax system was expected to increase tax compliance based on fairness perceptions, allowing for the opposite effect due to higher complexity. Furthermore, it was assumed that performance and tax payments would be influenced by motives of self-interest. The design included 20 rounds with a real-effort task in each round, determining participants’ experimental income. Participants (N = 191) made decisions about their tax payments from round-to-round in four different experimental conditions: (1) a flat tax system, (2) a progressive tax system, (3) starting with a flat and changing to a progressive, and (4) starting with a progressive and changing to a flat tax system. Results indicate higher work performance in a progressive system. However, a change from a progressive tax system to a flat system led to increased tax compliance.     

Learning in experiments: Dynamic interaction of policy variables designed to deter tax evasion

While neoclassical economic theory sheds insight into the way that audit rates and penalty rates interact when individuals decide to declare income for taxation, it predicts far lower levels of compliance than observed levels of compliance. This paper analyses experimental responses to explore a dynamic interaction between audit and penalty rates as individuals learn how to comply with taxation. It compares the responses of subjects in experiments with responses that are predicted when individuals rely on an adaptive learning process (that offers information feedback about decision payoffs). This comparison suggests that learning is an important consideration when explaining differences between predicted and observed levels of tax compliance.     

基层民主自治进程中乡村计划生育政策落实的困境及出路——基于基层治理中“不出事逻辑”的分析视角

本文对基层民主自治进程中乡村计划生育政策落实的困境及出路进行了探讨。基层民主自治是我国的一项基本政治制度,实行基层民主自治是发展中国特色社会主义民主政治的重要内容。但是在乡村推行基层民主自治的过程中,乡村计划生育政策的落实陷入一些困境,这些困境集中表现为计生政策与村民生育愿望、与村委会选举、与社会保障体系、与利益导向机制及与其它相关部门和政策的冲突与矛盾。鉴于此,本文相对应地提出了加强宣传教育、完善村民自治、健全社会保障体系、健全舆论导向机制以及加强政策的同向性与协调度等对策建议,以期推动计划生育政策在乡村进一步落实。     

The backfiring effect of auditing on tax compliance

Using country-level data from 2003–2014, we examine the association between auditing level (measured as number of verification actions taken by tax authorities per 100 taxpayers in each country) and tax compliance (measured as business executives’ perception of tax evasion). Our hypothesis is that compliance increases until a certain auditing level is reached, and decreases beyond that level (i.e., an elevated auditing level backfires). In line with our expectation, the results of a series of tests indicate that there is a U-shaped association between auditing and tax evasion. We discuss how a potential backfiring effect may depend on the extent to which compliance is voluntary.     

Social network and content analysis of the North American Carbon Program as a scientific community of practice

The North American Carbon Program (NACP) was formed to further the scientific understanding of sources, sinks, and stocks of carbon in Earth's environment. Carbon cycle science integrates multidisciplinary research, providing decision-support information for managing climate and carbon-related change across multiple sectors of society. This investigation uses the conceptual framework of communities of practice (CoP) to explore the role that the NACP has played in connecting researchers into a carbon cycle knowledge network, and in enabling them to conduct physical science that includes ideas from social science. A CoP describes the communities formed when people consistently engage in shared communication and activities toward a common passion or learning goal. We apply the CoP model by using keyword analysis of abstracts from scientific publications to analyze the research outputs of the NACP in terms of its knowledge domain. We also construct a co-authorship network from the publications of core NACP members, describe the structure and social pathways within the community. Results of the content analysis indicate that the NACP community of practice has substantially expanded its research on human and social impacts on the carbon cycle, contributing to a better understanding of how human and physical processes interact with one another. Results of the co-authorship social network analysis demonstrate that the NACP has formed a tightly connected community with many social pathways through which knowledge may flow, and that it has also expanded its network of institutions involved in carbon cycle research over the past seven years.     

试论金代的桑税

金代桑税渊源于辽和北宋的桑税制度.金代在继承辽宋桑税制度的同时,也进一步发展了自己的桑税制度.这表现为:一方面金代两税中的全部税绢都依据桑税征收,从而提高了它在两税中的地位;另一方面金代确立了旨在规定民户最低桑税额的桑地制度.金代桑税并非"户调",而是金代土地税的基本内容,也是金代两税的重要组成部分.     

完善我国个人所得税制的思考

个人所得税是调节国家与个人利益分配关系的重要杠杆,随着我国经济的快速发展、居民收入水平的大幅提高,个人所得税将是一项最有前途、最有发展潜力的税种。但我国个人所得税政策不尽人意,执行起来既失公平,又欠效率。文章分析了我国个人所得税制存在的问题,提出了相应的对策。     

Reciprocal relationships in tax compliance decisions

Reciprocity considerations are important to the tax compliance problem as they may explain the global dynamics of tax evasion, beyond individual tax evasion decisions, toward a downward or upward spiral. To provide evidence on reciprocity in tax compliance decisions, we have conducted a laboratory experiment in which we introduced two types of inequities. The first type of inequity is called vertical, because it refers to inequities introduced by the government when it sets different fiscal parameters for identical taxpayers, while the second type of inequity is called horizontal because it refers to the fact that taxpayers may differ in tax compliance decisions. In this setting, taxpayers may react to a disadvantageous or advantageous inequity through negative or positive reciprocal behaviors, respectively. Our results support the existence of negative and positive reciprocity in both vertical and horizontal cases. When both inequities come into play and may induce reciprocal behaviors in opposite directions, the horizontal always dominates the vertical.