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51.
燃气管道入廊后表现出了良好的性能和潜力,对于提高燃气管道运维安全性具有重要意义。但应对突发事件,国内现行标准规范仅在事故风机启动要求、管道阀门切断要求等方面做了简单规定,可操作性不强。从燃气管道入廊安全技术角度出发,总结分析相对成熟的直埋燃气管道事故处置技术,重点论述在编制现场处置方案过程中存在的主要矛盾,并对廊内燃气管道泄漏现场处置方案编制思路和内容提出建议。  相似文献   
52.
We examine natural disasters and long‐run climatic factors as potential determinants of international migration, implementing a panel dataset of bilateral migration flows from 1960 to 2000. We find no direct effect of long‐run climatic factors on international migration across our entire sample. These results are robust when conditioning on origin‐country characteristics, when considering migrants returning home, and when accounting for the potential endogeneity of migrant networks. Rather, we find evidence of indirect effects of environmental factors operating through wages. We find that epidemics and miscellaneous incidents spur international migration, and there is strong evidence that natural disasters beget greater flows of migrants to urban environs.  相似文献   
53.
Using a two-country dynamic optimization model where the less patient country decumulates and the more patient one accumulates wealth, we analyze spillover effects of lump-sum and consumption taxes. A lump-sum tax on a country definitely harms the other country through a change in the rate of interest. A lump-sum tax on either country always improves the less patient country's asset position. A consumption tax has no spillover effect, although it is Pareto-inferior. Applying these results into a closed-country context with heterogeneous agents, we also discuss policy implications of a discriminatory tax.  相似文献   
54.
Aims: The primary aim of this study was to perform a mapping of the EORTC-QLQ-C30 scores to EQ-5D-3L for the SIRFLOX study; a large dataset of patients with previously untreated liver-only or liver-dominant metastatic colorectal cancer (mCRC). A secondary aim was to compare the predictive validity of existing mappings from EORTC-QLQ-C30 to EQ-5D-3L conducted in other cancers.

Methods and materials: Questionnaires (completed within 529 patients) were used in a linear mixed regression to model EQ-5D-3L utility values (scored using the UK tariff) as a function of the five function scores, nine symptom scores, and the global score from the EORTC-QLQ-C30 questionnaire. A Tobit regression was also performed. The mean EQ-5D-3L values for the SIRFLOX trial were calculated and compared with predicted EQ-5D-3L values derived using published mapping algorithms.

Results: The linear mixed regression model provided a satisfactory mapping between the EORTC-QLQ-C30 and the EQ-5D-3L, whilst the Tobit model did not perform as well. When utilities from the SIRFLOX data were calculated with previously published mapping studies, three out of five studies performed well (< 10% mean difference).

Limitations: The main limitation of the study was the lack of meaningful observations post-progression (67 paired observations). For this reason, this study was unable to test whether the mapping holds by disease stage. Additionally, although the study adds to the literature of mappings to the EQ-5D-3L, it is not known how results would differ using the EQ-5D-5L.

Conclusion: This study is the first of its kind in liver-only or liver-dominant mCRC, and mCRC in general. The mapping constructed showed a good fit to the data and provides practitioners with an additional mapping between EORTC-QLQ-C30 to EQ-5D-3L using a large dataset (529 patients, 707 paired observations). The study also confirmed the generalizability of mappings published by Proskorovsky, Kontodimopoulos, and Longworth to liver-only or liver-dominant mCRC.  相似文献   

55.
Abstract

The paper reconstructs the history of the experimental attempts to measure the cardinal utility of money between 1950 and 1985 within the framework provided by expected utility theory (EUT). It is shown that this history displays a definite trajectory: from the confidence in EUT and the EUT-based measurement of utility of the 1950s to the scepticism that, from the mid-1970s, haunted the validity of EUT as well as the significance of the utility measures obtained through it. By exploring the diverse aspects and causes of this trajectory, the paper covers new ground in the history of both decision theory and utility measurement.  相似文献   
56.
Jian Chen  Chenghu Ma 《Applied economics》2016,48(35):3277-3292
This article proposes a novel way of pricing S&P 500 index options in the presence of jump risk. Our analysis is built upon an equilibrium option pricing rule for a representative agent economy. In particular, we use the weighted utility’s certainty equivalent to specify agent’s risk preference, which displays a fanning-out characteristic. We find that the fanning effect captures a remarkably large portion of the total market risk premium implicit in options. As a result, the model with fanning effect generates pronounced volatility smirks.  相似文献   
57.
There is now a growing consensus that ratifying International Environmental Agreements (IEAs) is the most effective way to tackle transboundary pollution problems. While the social benefit function (SBF) critically affects emission choices as well as decisions to ratify IEAs, the related economic literature has mainly concentrated on scenarios where the marginal SBF is linear. Using climatic data, I find that the linear marginal SBF case does not match data and isoelastic SBFs fit data better. In the more realistic, but not yet explored, context of isoelastic SBFs, I reconsider incentives to ratify IEAs. My analysis gives rise to novel conclusions. For instance, changes in the scale of damages do not affect the level of cooperation. When the scale of damages is small, variations of the SBF parameter reveal that large coalitions including the coalition of all countries are stable, but only when the potential gain from cooperation is sufficiently high.  相似文献   
58.
A portfolio choice model in continuous time is formulated for both complete and incomplete markets, where the quantile function of the terminal cash flow, instead of the cash flow itself, is taken as the decision variable. This formulation covers a wide body of existing and new models with law‐invariant preference measures, including expected utility maximization, mean–variance, goal reaching, Yaari's dual model, Lopes' SP/A model, behavioral model under prospect theory, as well as those explicitly involving VaR and CVaR in objectives and/or constraints. A solution scheme to this quantile model is proposed, and then demonstrated by solving analytically the goal‐reaching model and Yaari's dual model. A general property derived for the quantile model is that the optimal terminal payment is anticomonotonic with the pricing kernel (or with the minimal pricing kernel in the case of an incomplete market if the investment opportunity set is deterministic). As a consequence, the mutual fund theorem still holds in a market where rational and irrational agents co‐exist.  相似文献   
59.
We consider a consumption and investment problem where the market presents different regimes. An investor taking decisions continuously in time selects a consumption–investment policy to maximize his expected total discounted utility of consumption. The market coefficients and the investor's utility of consumption are dependent on the regime of the financial market, which is modeled by an observable finite-state continuous-time Markov chain. We obtain explicit optimal consumption and investment policies for specific HARA utility functions. We show that the optimal policy depends on the regime. We also make an economic analysis of the solutions, and show that for every investor the optimal proportion to allocate in the risky asset is greater in a "bull market" than in a "bear market." This behavior is not affected by the investor's risk preferences. On the other hand, the optimal consumption to wealth ratio depends not only on the regime, but also on the investor's risk tolerance: high risk-averse investors will consume relatively more in a "bull market" than in a "bear market," and the opposite is true for low risk-averse investors.  相似文献   
60.
The oldest industry in Australia subjected to economic regulation is the gas supply industry in the state of New South Wales. In this paper the aims and motivation of the New South Wales Government in establishing the regulatory regime in 1912 and the subsequent effectiveness in achieving them are determined. Initially the regulatory regime was based on ad hoc arrangements, but eventually a more permanent structure was devised that effectively defused political controversy over gas market pricing and stabilised prices rather than substantially lowered them.  相似文献   
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