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1.
We develop a dynamic model of democratic politics in which both potential office holders and the electorate have heterogeneous ideologies. Voters have incomplete information about candidate ideologies, so they must use information from previous positions taken in office to make informed re-election decisions. We characterize the effects of term limits on the evolution over time of the ideological positions taken by office holders and derive the implications for voter choice and welfare. Contributions of our paper include:
We detail how pork provision by more senior incumbents interacts with term limits to affect electoral outcomes. Pork provision—transfers of resources from districts with junior legislators to districts with more senior legislators—induces voters to be more forgiving of extreme location by incumbents, especially incumbents in small or poor districts. Pork provision can explain why re-election probabilities in Congress exceed those for governors.
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Term limits reduce voter welfare when all that matters are the ideological positions taken by the office holder.
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Term limits may be advantageous when senior incumbents can extract benefits for their constituencies at the expense of districts with more junior representatives. Large or rich districts especially value term limits when there is substantial pork provision.
We characterize the welfare of all voters, not just the median voter.
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2.
Literature-Related Discovery (LRD): Introduction and background   总被引:1,自引:0,他引:1  
Discovery in science is the generation of novel, interesting, plausible, and intelligible knowledge about the objects of study. Literature-related discovery (LRD) is the linking of two or more literature concepts that have heretofore not been linked (i.e., disjoint), in order to produce novel, interesting, plausible, and intelligible knowledge (i.e., potential discovery). LRD has two main components that differ in their methodological approach to discovery:
Literature-based discovery (LBD) produces potential discovery through analysis of the technical literature alone.
Literature-assisted discovery (LAD) produces potential discovery through both analysis of the technical literature and use of selected authors of that literature. These authors generate potential discovery as proposers, workshop/panel participants, or in other active roles.
LRD offers the promise of large amounts of potential discovery, for the following reasons:
the burgeoning technical literature contains a very large pool of technical concepts in myriad technical areas;
researchers spend full time trying to cover the literature in their own research fields and are relatively unfamiliar with research in other especially disparate fields of research;
the large number of technical concepts (and disparate technical concepts) means that many combinations of especially disparate technical concepts exist
by the laws of probability, some of these combinations will produce novel, interesting, plausible, and intelligible knowledge about the objects of study.
This Special Issue presents the LRD methodology and voluminous discovery results from five problem areas: four medical (treatments for Parkinson's Disease (PD), Multiple Sclerosis (MS), Raynaud's Phenomenon (RP), and Cataracts) and one non-medical (Water Purification (WP)). In particular, the open discovery systems (ODS) aspect of LRD (start with problem, generate potential solution(s), or vice versa) is addressed, rather than the closed discovery systems (CDS) aspect (start with problem and potential solution(s), generate linking mechanism(s)). In the presentation of potential discovery, a ‘vetting’ process is used that insures both requirements for ODS LBD are met: concepts are linked that have not been linked previously, and novel, interesting, plausible, and intelligible knowledge is produced.The potential discoveries for the PD, MS, Cataracts, and WP problems are the first we have seen reported by this ODS LBD approach, and the numbers of potential discoveries for the ODS LBD benchmark RP problem are almost two orders of magnitude greater than those reported in the open literature by any other ODS LBD researcher who has addressed this benchmark RP problem. The WP problem is the first non-medical technical topic to have been addressed successfully by ODS LBD.In all cases, but especially the medical, we have barely scratched the surface of quantity and quality of potential discovery that could be generated with adequately resourced studies. Based on the many potential discoveries we have obtained, and the promise of far more potential discoveries with adequately resourced studies, we have generated a new paradigm relative to discovery: while the key challenge in traditional discovery is finding a needle-in-a-haystack, the key challenge in ODS LRD (used appropriately) is handling the overwhelming amount of potential discovery available.Additionally, it is our thesis, as the specific ODS LBD studies will demonstrate, that synergistic combinations of our mainly individual potential discoveries are themselves potential discoveries. We demonstrate throughout this Special Issue the synergistic effects of combining a very few potential discoveries or interesting core literature concepts, and believe that these synergistic benefits are operable at larger scales of combination. In the final lessons-learned paper of this Special Issue, we also show that providing evidence for the synergistic benefits of large numbers of potential discoveries or interesting core concepts is very difficult due to the large numbers of potential combinations involved.One variant of the LAD operational mode (identifying disparate discipline recipients for Broad Agency Announcement (BAA) notifications in order to stimulate proposals of new ideas from these disparate disciplines) is presented for WP. Other possible applications of LAD include:
1.
Recipients of solicitation announcements (other solicitations similar to BAA, journal Special Issue calls for papers, etc),
2.
Participants in Workshops, Advisory Panels, Review Panels, Roadmaps, and War Games,
3.
Points of Contact for Field Science Advisors, Foreign Field Offices, Program Officer site visits, and potential transitions.
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3.
This paper describes work undertaken in the MATISSE project to explore the potential for a sustainable hydrogen transition within Europe and the implications for infrastructure investment. Stakeholder engagement work conducted within MATISSE identified unsustainable aspects of current transport and desirable characteristics of sustainable hydrogen road transport. Key criteria were: emissions reduction, security of energy supply, affordability and economic competitiveness.Results from the ASTRA model show that a transition to hydrogen transport fuels would have an increase in GDP, employment and investment; and growth in a number of sectors (electronic, chemical, mechanical and automotive) associated with hydrogen fuel cell technology. A hydrogen diffusion model shows that in a few years after 2040 all cars in Germany could be hydrogen driven cars. Fast build-up of a network of at least 500 filling stations (in urban areas and at highways) is very important for the market acceptance of hydrogen vehicles and compared with subsidies for vehicles and fuel the necessary investments are very small. For fuel infrastructure:
Only a total amount of approx. 200 million Euros are necessary for infrastructure build-up in urban areas.
Additional support is needed for installation of hydrogen filing stations on highways (approx. 100 million Euros).
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4.
Economic and psychological literature mentions three conditions under which the crowding-out effect of pro-social behaviour is likely to occur and to crowd out citizens' moral obligations to behave co-operatively. I use a framed field experiment on joint extraction from a common-pool resource (CPR) where the crowding-out effect has already been reported before in combination with the trust game carried out in farming communities of Namibia and South Africa to replicate these conditions. The research design and the cross-cultural setting enable to explicitly control for these effects. The results of the experiments support that the crowding-out effect depends on:
The nature of the external intervention (controlling vs. supportive external intervention)
The degree of participants self-determination (high vs. low self-determination in the group)
A society's norms of trust and reciprocity (high vs. low trust within the society)
The results imply that outside regulations aiming to conserve natural resources risk worsening the situation when neglecting democratic legitimization as well as local community norms.  相似文献   

5.
This paper presents the strategy for a large EU-funded Integrated Project: EXIOPOL (“A New Environmental Accounting Framework Using Externality Data and Input-Output Tools for Policy Analysis”), with special attention for its part in environmentally extended (EE) input-output (IO) analysis. The project has three principal objectives:
(a)
to synthesize and further develop estimates of the external costs of key environmental impacts for Europe;
(b)
to develop an EE IO framework for the EU-27 in a global context, including as many of these estimates as possible, to allow for the estimation of environmental impacts (expressed as LCA themes, material requirement indicators, ecological footprints or external costs) of the activities of different economic sectors, final consumption activities and resource consumption;
(c)
to apply the results of the work to external costs and EE I-O for illustrative policy questions.
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This paper extends a broad functional category approach for the study of technological capability progress recently developed and applied to information technology to a second key case—that of energy based technologies. The approach is applied to the same three functional operations—storage, transportation and transformation—that were used for information technology by first building a 100 plus year database for each of the three energy-based functional categories. In agreement with the results for information technology in the first paper, the energy technology results indicate that the functional approach offers a stable methodology for assessing longer time technological progress trends. Moreover, similar to what was found with information technology in the first study, the functional capability for energy technology shows continual—if not continuous—improvement that is best quantitatively described as exponential with respect to time. The absence of capability discontinuities—even with large technology displacement—and the lack of clear saturation effects are found with energy as it was with information. However, some key differences between energy and information technology are seen and these include:
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Lower rates of progress for energy technology over the entire period: 19-37% annually for Information Technology and 3-13% for Energy Technology.
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Substantial variability of progress rates is found within given functional categories for energy compared to relatively small variation within any one category for information technology. The strongest variation is found among capability progress among different energy types.
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More challenging data recovery and metric definition for energy as compared to information technology.
These findings are interpreted in terms of fundamental differences between energy and information including the losses and efficiency constraints on energy. We apply Whitney's insight that these fundamental differences lead to naturally modular information technology artifacts. The higher progress rates of information-based as opposed to energy-based technologies follows since decomposable systems can progress more rapidly due to the greater ease of independent as opposed to simultaneous development. In addition, the broad implications of our findings to studies of the relationships between technical and social change are briefly discussed.  相似文献   

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This paper describes some important frontiers of futures research with the aim of identifying new opportunities for improving the value and utility of the field. These frontiers include the exploration and/or the reexamination of
(a) Potential for integrating new technology with futures research methods,
(b) Ways to reduce the domain of the unknowable,
(c) Ways to account for uncertainty in decision making,
(d) Strategies for planning and management of nonlinear systems operating in the chaotic regime,
(e) Ways to improve understanding of psychological factors that lead to irrational decisions
(f) Appropriate levels of aggregation in investigation of forecasting problems.
(g) The potential offered by new sources of social data.
Keywords: Futures research methodology; New technologies; Decision making; Uncertainty; Non-linear systems; Futures methodology issues  相似文献   

13.
Commuters route choice behaviour   总被引:3,自引:0,他引:3  
The paper reports laboratory experiments with a two route choice scenario. In each session 18 subjects had to choose between a main road M and a side road S. The capacity of M was larger. Feedback was given in treatment I only on the subjects' own travel time and in treatment II on travel time for M and S. The main results are as follows:
• Mean numbers on M and S are near to pure equilibrium.
• Fluctuations persist until the end of the sessions.
• The total number of changes is significantly greater in treatment I.
• Subjects' road changes and payoffs are negatively correlated.
• A direct response mode results in more changes for bad payoffs whereas a contrary response mode shows opposite reactions.
• Simulations of an extended payoff sum learning model fits the main results of the statistical evaluation of the data.
Keywords: Travel behaviour; Information in intelligent transportation systems; Day-to-day route choice; Laboratory experiments; Payoff sum model  相似文献   

14.
A systematic two-component approach (front-end component, back-end component) to bridging unconnected disciplines and accelerating potentially radical discovery and innovation (based wholly or partially on text mining procedures) is presented. The front-end component has similar objectives to those in the classical literature-based discovery (LBD) approach, although it is different mechanistically and operationally. The front-end component will systematically identify technical disciplines (and their associated leading experts) that are directly or indirectly-related to solving technical problems of high interest. The back-end component is actually a family of back-end techniques, only one of which shares the strictly literature-based analysis of the classical LBD approach. The non-LBD back-end techniques (literature-assisted discovery) make use of the human experts associated with the disparate literatures (disciplines) uncovered in the front-end to generate radical discovery and innovation.Specifically, in the literature-assisted discovery operational mode, these disparate discipline experts could be used as:
1. Recipients of solicitation announcements (BAA, SBIR, MURI, journal Special Issue calls for papers, etc.),
2. Participants in Workshops, Advisory Panels, Review Panels, Roadmaps, and War Games,
3. Points of Contact for Field Science Advisors, Foreign Field Offices, Program Officer site visits, and potential transitions.
Keywords: Discovery; Innovation; Science and technology; Text mining; Literature-based discovery; Literature-assisted discovery; Radical discovery; Radical innovation; Information retrieval; Unconnected disciplines; Disparate disciplines; Interdisciplinary; Multidisciplinary; Solicitations; Special issues; Workshops; Roadmaps; Advisory panels; Review panels; War games  相似文献   

15.
Abstract

Objective:

To identify the direct and indirect costs of hypoglycemia in patients with Type 1 or Type 2 diabetes mellitus (DM) in the US setting.  相似文献   

16.
It is argued if xt ~ I(1) and yt ~ I(1), then running a regression xt on yt would produce spurious results because e t would generally be I(1). However, there may exist a ‘b’ such that e t  = x t - by t is I(0), then running a regression x t on y t would not produce spurious results. This special case of two integrated time series is known in the literature as cointegration. In this particular case, x t and y t are said to be cointegrated. In our review of the development of the concept of cointegration, we identified that the underlying reason for this special case to arise is the proposition that if x t  ~ I(d x ), y t  ~ I(d y ), then z t  = bx t  + cy t  ~ I(max(d x ,d y )). In this research, we offer evidence against this proposition.  相似文献   

17.
In this paper we consider the standard voting model with a finite set of alternatives A and n voters and address the following question: what are the characteristics of domains \({\mathcal D}\) that induce the property that every strategy-proof social choice function \({f: {\mathcal D}^n \rightarrow A}\) satisfying unanimity, has the tops-only property? We first impose a minimal richness condition which ensures that for every alternative a, there exists an admissible ordering where a is maximal. We identify conditions on \({\mathcal D}\) that are sufficient for strategy-proofness and unanimity to imply tops onlyness in the general case of n voters and in the special case, n = 2. We provide an algorithm for constructing tops-only domains from connected graphs with elements of A as nodes. We provide several applications of our results. Finally, we relax the minimal richness assumption and partially extend our results.  相似文献   

18.
Abstract

Objective:

This study aims to estimate the long-term cost-effectiveness of saxagliptin?+?metformin (SAXA?+?MET) vs glimepiride?+?metformin (GLI?+?MET) in patients with Type 2 diabetes mellitus (T2DM) inadequately controlled with MET in China.  相似文献   

19.
This study analyzes the persistency of total and disaggregated Turkish exports for different shock magnitudes using the quantile autoregression (QAR) method in line with Koenker and Xiao (J Am Stat Assoc 99:775–787, 2004). The results suggest that the persistence of shocks are not similar across different quantiles of Total Exports and disaggregated export sectors, indicating an asymmetry in the case of negative and positive shocks across different export sectors. The persistency behavior of Total Exports as well as Food and Beverages, Chemicals, Basic Metals, Raw Materials, Motor Vehicles and Radio & TV exports are asymmetric to negative versus positive shocks, which cannot be captured by traditional unit root tests. Thus, sound interpretation of QAR results is necessary for policy makers to identify shock characteristics and thereby pursue appropriate policies for overcoming adverse impacts on the economy.  相似文献   

20.
This paper investigates whether individuals might voluntarily join and remain members of a state in which high levels of social insurance are provided. That is to say, are there plausible circumstances in which a social welfare state can be regarded as “liberal” in the sense that it has the universal support of its citizens?As a point of departure, the paper demonstrates that risk-averse individuals in a setting of substantial income or health uncertainty will voluntarily join private income-security clubs. Private income-security clubs, however, cannot be entirely voluntary because they must solve the problem of adverse selection, as with entry or exit fees. The paper demonstrates that individuals may opt for governmental provision of income security services, when there is uncertainty about the quality of private club services, because naturally high exit costs allow national governments to economically address the problem of adverse selection. The analysis also suggests that liberal income security programs may have constitutional or quasi-constitutional status because of the nature of the long-term nature of the insurance contract.  相似文献   

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