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1.
Fiscal transparency entails fiscal information disclosure, ensuring good quality of such information, public and parliamentary scrutiny, and the oversight of fiscal risks, while the concept of budget credibility involves an assessment of the extent of conformity of budgetary outturn to the planned forecasts. There are two main channels through which fiscal transparency can affect budget credibility: politicians' incentives to manipulate fiscal forecasts or deviate from the plans, and the uncertainty‐reducing effect in the light of fiscal risks. This study empirically examines the impact of the dimensions of fiscal transparency on deviations from budgetary forecasts, and hence budget credibility, in developing countries using regression analysis. The results show that an improvement in the oversight of fiscal risks arising from public sector entities plays a very significant role in decreasing the deviations from budgetary forecasts in developing countries. The study accords with the view that a relatively less important weight should be attached to the fiscal disclosure component in analyzing fiscal transparency, and it sheds light on the importance of ensuring good quality of disclosed information through more independence of audit bodies in developing countries in order to enhance the credibility of their budgets.  相似文献   

2.
The stochastic properties of conventionally denned federal expenditures and revenues are examined, and cointegration is found. Alternative time-series models-univariate ARIMA models, vector autoregressions in levels and differences, and an error correction model-are specified and estimated using quarterly data from 1955:1 through 1979:4. Updated forecasts for up to three years beyond the sample period are evaluated against actual expenditures, revenues and the deficit. The vector autoregression in levels shows evidence of nonstationarity, which leads to strong biases in the forecasts. The remaining models produce forecasts that are satisfactory by the mean squared error criterion, and the magnitudes of biases at the longer horizons are significantly smaller than those of the official forecasts.  相似文献   

3.
Summary Scorpion larvae spend their first larval stage settled on their mother's back. Isolated larvae can also survive, but their survival probability is lower than it is if they remain on the back of the mother. Experiments with tritiated water suggest that a water exchange must take place between mother and larvae.  相似文献   

4.
Optimization of energy use by evolving organisms, predicted by theoretical extensions of the neo-Darwinian theory, i. contrasted with that of irreversible thermodynamics, which predicts an increase in orderliness and thus an increase in energy consumption per unit of biomass. We compared this index with estimates of social complexity among ant genera and species. Our results show that simple optimization models cannot explain experimental data, and that social complexity correlates differently with negentropy at different levels of analysis. Comparing the genera among Formicidae, workers (not colonies) from genera with highly social species are less negentropic than those of socially primitive ones. At the sub-generic level, social complexity correlated positively with negentropy among species, for major workers inAcromyrmex and for minor workers inAtta. The results illustrate the complexity of thermodynamic criteria in the study of evolution but also hint at their usefulness. In this case, they show that two different evolutionary routes to the complex Attini ant societies may exist.  相似文献   

5.
Conclusion Sleep is not only the output of an EEG machine but a global phenomenon with unique physiological, environmental and psychological features occurring in a given individual. There is no question that statistical evaluation of noise-induced sleep disturbances in non homogeneous groups of subjects has resulted in the construction of a magnificent neurophysiological edifice by assembling a few individual bricks. In this respect, whether subjectively disturbed or not, we now know that when we sleep in noisy areas our delta sleep is reduced, our heart rate fails to habituate to individual noises, and we are more likely to develop psychic disturbances than residents in quiet areas. Data from these studies are however interspersed with results from a number of experiments during which the subject has been looked upon as nothing but a sleeper, i.e., experiments in which day-time stresses and noises were considered as irrelevant for the night-time study. It seems important therefore that future studies should gather more longitudinal data based on a limited number of subjects selected according to their day-time habits and psychological (e.g., extroverts/introverts) and physiological (e.g., short or long sleepers) characteristics. The knowledge about these situational factors and personality traits might provide new insights into individual biological strategies developed to cope with noise stress. The difficulties in assessing the effect of noise on sleep are particularly obvious if we consider another finding: deaf subjects spend significantly less time in delta sleep than do control subjects47 and they present sleep pattern alterations remarkably similar to those which are most consistently described in noisy conditions.Research by the authors has been supported by grants from the Ministère de la Qualité de la Vie et de l'Environnement (France) and Commission of European Communities.  相似文献   

6.
Summary The occurrence in animal phyla of species having a relatively transparent body is noted and measurements of the transmittance of medusae made in a spectrophotometer are reported, but the approximate nature of the results obtained with a commercial instrument and the importance of the correct physical design of the measuring apparatus are emphasized. The application to invertebrates of the structural explanation of the predominant transmission of incident light by the vertebrate cornea is discussed and the role of other factors considered. Destructive interference of the scattered rays, sufficient to account for the transparency of the cornea, has been shown not to demand a completely regular arrangement of collagen fibres. The small diameter and regularity of the fibrillar components in the muscles ofSagitta may be adequate to account for their transparency.I am grateful to Dr.D. M. Maurice for the encouragement of this interest, to Dr.E. G. Jordan for electron micrographs ofSagitta and to Mr.G. Ross (Department of Physics, Queen Elizabeth College) for helpful and critical discussion.  相似文献   

7.
In the past, clinical trials transplanting bone marrow–derived mononuclear cells reported a limited improvement in cardiac function. Therefore, the search for stem cells leading to more successful stem cell therapies continues. Good candidates are the so-called cardiac stem cells (CSCs). To date, there is no clear evidence to show if these cells are intrinsic stem cells from the heart or mobilized cells from bone marrow. In this study we performed a comparative study between human mesenchymal stem cells (hMSCs), purified c-kit+ CSCs, and cardiosphere-derived cells (CDCs). Our results showed that hMSCs can be discriminated from CSCs by their differentiation capacity towards adipocytes and osteocytes and the expression of CD140b. On the other hand, cardiac progenitors display a greater cardiomyogenic differentiation capacity. Despite a different isolation protocol, no distinction could be made between c-kit+ CSCs and CDCs, indicating that they probably derive from the same precursor or even are the same cells.  相似文献   

8.
在测度四个直辖市产业结构合理化和产业结构高级化的基础上,研究了产业结构对经济增长、物价稳定、就业充分、对外贸易均衡的影响。研究结果表明:产业结构合理化和产业结构高级化对宏观经济指标均具正向作用。其中,对前三个指标,产业结构合理化比高级化时宏观经济的影响更加显著,并表现出较好的稳定性,高级化则表现出较大的不确定性。而在对外贸易均衡指标的影响上,产业结构高级化比合理化更加显著。  相似文献   

9.
Modern scientific knowledge is increasingly collaborative. Much analysis in social epistemology models scientists as self-interested agents motivated by external inducements and sanctions. However, less research exists on the epistemic import of scientists’ moral concern for their colleagues. I argue that scientists’ trust in their colleagues’ moral motivations is a key component of the rationality of collaboration. On the prevailing account, trust is a matter of mere reliance on the self-interest of one’s colleagues. That is, scientists merely rely on external compulsion to motivate self-interested colleagues to be trustworthy collaborators. I show that this self-interest account has significant limitations. First, it cannot fully account for trust by relatively powerless scientists. Second, reliance on self-interest can be self-defeating. For each limitation, I show that moral trust can bridge the gap—when members of the scientific community cannot rely on the self-interest of their colleagues, they rationally place trust in the moral motivations of their colleagues. Case studies of mid-twentieth-century industrial laboratories and exploitation of junior scientists show that such moral trust justifies collaboration when mere reliance on the self-interest of colleagues would be irrational. Thus, this paper provides a more complete and realistic account of the rationality of scientific collaboration.  相似文献   

10.
In a conditional predictive ability test framework, we investigate whether market factors influence the relative conditional predictive ability of realized measures (RMs) and implied volatility (IV), which is able to examine the asynchronism in their forecasting accuracy, and further analyze their unconditional forecasting performance for volatility forecast. Our results show that the asynchronism can be detected significantly and is strongly related to certain market factors, and the comparison between RMs and IV on average forecast performance is more efficient than previous studies. Finally, we use the factors to extend the empirical similarity (ES) approach for combination of forecasts derived from RMs and IV.  相似文献   

11.
In previous works, I examine inferential methods employed in Probabilistic Weather Event Attribution studies (PEAs), and explored various ways they can be used to aid in climate policy decisions and decision-making about climate justice issues. This paper evaluates limitations of PEAs and considers how PEA researchers’ attributions of “liability” to specific countries for specific extreme weather events could be made more ethical. In sum, I show that it is routinely presupposed that PEA methods are not prone to inductive risks and presuppose that PEA researchers thus have no epistemic consequences or responsibilities for their attributions of liability. I argue that although PEAs are nevertheless crucially useful for practical decision-making, the attributions of liability made by PEA researchers are in fact prone to indicative risks and are influenced by non-epistemic values that PEA researchers should make transparent to make such studies more ethical. Finally, I outline possible normative approaches for making sciences, including PEAs, more ethical; and discuss implications of my arguments for the ongoing debate about how PEAs should guide climate policy and relevant legal decisions.  相似文献   

12.
The so-called reactive oxygen species (ROS) are defined as oxygen-containing species that are more reactive than O(2) itself, which include hydrogen peroxide and superoxide. Although these are quite stable, they may be converted in the presence of transition metal ions, such as Fe(II), to the highly reactive oxygen species (hROS). hROS may exist as free hydroxyl radicals (HO·), as bound ("crypto") radicals or as Fe(IV)-oxo (ferryl) species and the somewhat less reactive, non-radical species, singlet oxygen. This review outlines the processes by which hROS may be formed, their damaging potential, and the evidence that they might have signaling functions. Since our understanding of the formation and actions of hROS depends on reliable procedures for their detection, particular attention is given to procedures for hROS detection and quantitation and their applicability to in vivo studies.  相似文献   

13.
We presented people with trended and untrended time series and asked them to estimate the probability that the next point would be below each of seven different reference values. The true probabilities that the point would be below these values were 0.01, 0.10, 0.25, 0.50, 0.75, 0.90 and 0.99. People overestimated probabilities of less than 0.50 and underestimated those of more than 0.50. Consequently, their subjective probability distributions were flatter than they should have been: people appeared to be under confident in their estimates of where the next point would lie. This bias was greater for the trended series. It was also greater in a second experiment in which people estimated the probability that the next item would be above the reference values. We discuss reasons for these effects and consider their implications for decision making.  相似文献   

14.
采用超临界CO2萃取法提取库尔勒香梨精油,用气相色谱-串联质谱技术对其成分进行分析,并对几种提取方法进行综合比较。结果表明,与水蒸气蒸馏法、固相微萃取法相比,超临界CO2萃取法具有香梨精油提取率最高,为0.0549%。感官分析的结果表明,超临界CO2萃取法所得的库尔勒香梨精油颜色为橙色透明液体,而且风味好。气相色谱-质谱联用(GC-MS)分析结果表明:超临界CO2萃取法所得的香梨精油中共鉴定出28种成分。丁酸乙酯、顺-7-十四烯-1-醇和乙酸己酯的含量最高,含量分别为5.19%、4.85%和4.37%。  相似文献   

15.
Recent years have seen the development of an approach both to general philosophy and philosophy of science often referred to as ‘experimental philosophy’ or just ‘X-Phi’. Philosophers often make or presuppose empirical claims about how people would react to hypothetical cases, but their evidence for claims about what ‘we’ would say is usually very limited indeed. Philosophers of science have largely relied on their more or less intimate knowledge of their field of study to draw hypothetical conclusions about the state of scientific concepts and the nature of conceptual change in science. What they are lacking is some more objective quantitative data supporting their hypotheses. A growing number of philosophers (of science), along with a few psychologists and anthropologists, have tried to remedy this situation by designing experiments aimed at systematically exploring people’s reactions to philosophically important thought experiments or scientists’ use of their scientific concepts. Many of the results have been surprising and some of the conclusions drawn from them have been more than a bit provocative. This symposium attempts to provide a window into this new field of philosophical inquiry and to show how experimental philosophy provides crucial tools for the philosopher and encourages two-way interactions between scientists and philosophers.  相似文献   

16.
Our paper discusses the epistemic attitudes of particle physicists on the discovery of the Higgs boson at the Large Hadron Collider (LHC). It is based on questionnaires and interviews made shortly before and shortly after the discovery in 2012. We show, to begin with, that the discovery of a Standard Model (SM) Higgs boson was less expected than is sometimes assumed. Once the new particle was shown to have properties consistent with SM expectations – albeit with significant experimental uncertainties –, there was a broad agreement that ‘a’ Higgs boson had been found. Physicists adopted a two-pronged strategy. On the one hand, they treated the particle as a SM Higgs boson and tried to establish its properties with higher precision; on the other hand, they searched for any hints of physics beyond the SM. This motivates our first philosophical thesis: the Higgs discovery, being of fundamental importance and establishing a new kind of particle, represented a crucial experiment if one interprets this notion in an appropriate sense. Duhemian underdetermination is kept at bay by embedding the LHC into the tradition of previous precision experiments and the experimental strategies thus established. Second, our case study suggests that criteria of theory (or model) preference should be understood as epistemic and pragmatic values that have to be weighed in factual research practice. The Higgs discovery led to a shift from pragmatic to epistemic values in physicists’ assessment of the mechanisms of electroweak symmetry breaking. Complex criteria, such as naturalness, combine epistemic and pragmatic values, but are coherently applied by the community.  相似文献   

17.
For analysts there is a tradeoff between the accuracy and the timeliness of their forecasts. Prior literature heavily investigates analyst forecast accuracy. Few papers investigate the importance of timeliness. To our best knowledge, there are no empirical papers to date to investigate the dynamic interplay between these key characteristics. We show that if analysts experience a period of high accuracy relative to their peers, they subsequently focus more on the timeliness of their forecasts in the subsequent period and thus issue their forecasts earlier than they did in the prior period. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

18.
Focusing on the interdependence of product categories we analyze multicategory buying decisions of households by a finite mixture of multivariate Tobit‐2 models with two response variables: purchase incidence and expenditure. Mixture components can be interpreted as household segments. Correlations for purchases of different categories turn out to be much more important than correlations among expenditures as well as correlations among purchases and expenditures of different categories. About 18% of all pairwise purchase correlations are significant. We compare the best‐performing large‐scale model with 28 categories to four small‐scale models each with seven categories. In our empirical study the large‐scale model clearly attains a better forecasting performance. The small‐scale models provide several biased correlations and miss about 50% of the significant correlations which the large scale model detects. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

19.
Larvae and adults of D. melanogaster and D. simulans were fed with acridine orange, in order to test sensitivity differences between the species. Our results show that, of the two species, D. simulans is more resistant in the larval stages, and D. melanogaster is more resistant in the adult stage. Furthermore, adult males of both species are more sensitive than adult females.  相似文献   

20.
Both philosophers and scientists have recently promoted transparency as an important element of responsible scientific practice. Philosophers have placed particular emphasis on the ways that transparency can assist with efforts to manage value judgments in science responsibly. This paper examines a potential challenge to this approach, namely, that efforts to promote transparency can themselves be value-laden. This is particularly problematic when transparency incorporates second-order value judgments that are underwritten by the same values at stake in the desire for transparency about the first-order value judgments involved in scientific research. The paper uses a case study involving research on Lyme disease to illustrate this worry, but it responds by elucidating a range of scenarios in which transparency can still play an effective role in managing value judgments responsibly.  相似文献   

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