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971.
Revised implied volatility curves and surfaces for the Chinese Yuan (CNY) exchange rate are obtained from market quotations for CNY non-deliverable options by solving an inverse problem of foreign exchange option pricing, which is calculated using a regularization approach in an optimal control framework. To take account of the market expectation for the CNY exchange rate, a stochastic adjusted factor is applied that follows a Vasicek model with parameters fitted from market quotations for CNY non-deliverable forwards. A well-posed numerical scheme is implemented.  相似文献   
972.
This paper uses primary data to analyze the institutions and informal markets that govern groundwater allocation in a sugarcane-cultivating village in North India. We find that, in contrast to earlier literature, the observed water trades result in efficient water allocation across farms. We interpret this and other stylized facts in terms of a social contract using a simple bargaining model with limited inter-player transfers. Poor functioning of the power sector leads to reduced pumping and a water supply constraint. Simulations show that power supply reform can significantly increase farm yields, and be financed out of increased farm profits.  相似文献   
973.
While the German economy may currently be a bright spot in Europe, it has faced substantial challenges in recent years. Moreover, tensions are rising regarding Germany's responsibilities and opportunities as a member of the European Monetary Union. Other studies have documented the difficulties that Germany has encountered as a result of the unification and further integration of Europe. This paper adds to that literature by using an aggregate translog cost function approach to examine the relationships among inputs of domestic capital and labour and imports. Our findings indicate that the input pairs of capital‐labour and labour‐imports are substitutes. The substitutes relationship between labour and imports, which has become stronger over time, suggests that increasing globalisation will add to Germany's unemployment woes. Capital and imports appear to be weak complements, but that relationship is not statistically significant. The results also suggest that imports are playing an increasingly important role in Germany's aggregate production, accentuating the role of the international environment.  相似文献   
974.
This exploratory study seeks to add to the income tax evasion literature by investigating a heretofore ignored potential determinant of aggregate federal personal income tax evasion in the U.S., namely, the labour force participation rate. It is hypothesized that the higher (lower) the labour force participation rate, the lower (greater) the degree of tax evasion. The empirical estimation supports this hypothesis, finding that a one unit (one percentage point) increase (decrease) in the labour force participation rate leads to a 9.1% decrease (increase) in income tax evasion. Thus, the declining labour force participation in recent years implies increased tax evasion problems for the U.S.  相似文献   
975.
We identify the presence of shirking by Major League Baseball umpires during indefinite unpaid overtime, as defined by extra innings. In the presence of new information about expected game length, umpires exert biases in ball and strike calls consistent with opportunistically reducing the likelihood of working additional time. General implications with respect to the effectiveness of salaried workers during unpaid overtime hours are discussed.  相似文献   
976.
Amiti and Weinstein proposed an estimation framework to disentangle credit demand and supply shocks using matched bank-firm loan data. Here, we show that their estimator can be generalized to capture shocks arising in an arbitrary number of dimensions. Our algorithm permits empirical researchers to analyse multi-dimensional data sets using the Amiti–Weinstein framework. This may be beneficial both for studies on micro-level outcomes as well as for the literature on assessing the macroeconomic impact of idiosyncratic shocks. In an empirical application to a firm-product-country export data set, we highlight the usefulness of the generalized Amiti–Weinstein estimator, and we demonstrate the importance of considering additional dimensions when gauging the effect of granular shocks on aggregate fluctuations.  相似文献   
977.
Background: Non-vitamin K antagonist oral anticoagulants (NOACs) have been included in international guidelines as important alternatives to vitamin K antagonists (VKAs) for the treatment of venous thromboembolism (VTE) and stroke prevention in non-valvular atrial fibrillation (NVAF). Meanwhile, in the Netherlands, NOACs are widely used next to VKAs. The objective of this study is to estimate the cost-effectiveness of treatment with rivaroxaban compared to VKAs in NVAF and VTE patients in the Netherlands, using data from international prospective observational phase IV studies.

Methods: Two models were developed to represent NVAF and VTE patients, populated with patients from the XANTUS (NCT01606995) and XALIA (NCT01619007) international prospective observational studies. The 1-year cost-effectiveness of rivaroxaban use, compared to VKAs, was explored in a population consisting of NVAF and VTE patients (base case) as well as for four scenarios with sub-populations: NVAF patients only, VTE patients only, NVAF patients with unstable international normalized ratio (INR), and NVAF patients using an INR self-measuring device.

Results: In the base case, rivaroxaban saved €72,350 and gained 21 quality-adjusted life-years (QALYs) in a simulation of 2,000 patients over the use of VKAs. Ergo, rivaroxaban was dominant over VKAs. The probabilistic sensitivity analysis showed a probability of 85% for rivaroxaban being dominant and 100% at a willingness-to-pay threshold of €20,000/QALY. Rivaroxaban appeared to be dominant in all scenarios as well, except for the NVAF-patients-only scenario where the incremental cost-effectiveness ratio (ICER) was €157/QALY.

Conclusions: In patients with NVAF or VTE, rivaroxaban treatment is likely to be cost-effective and a potentially cost-saving alternative to VKA in the Netherlands.  相似文献   

978.
Aims: Examine healthcare costs across chronic kidney disease (CKD) stages for US patients with type 2 diabetes (T2D).

Materials and methods: IQVIA Real World Data Adjudicated Claims linked electronic medical records and insurance claims from January 1, 2012 through March 31, 2017 were used for this retrospective study. Adults diagnosed with T2D and comorbid CKD were included. General linear models incorporating splines were constructed, and information from these regressions were used to inform the relationship between medical costs and CKD. Multivariable analyses controlled for patient characteristics, vital signs, general health, prior medication use, prior visit to specialists, index A1c, and year of index date.

Results: There were 6,645 individuals who met the study criteria. Results generally indicate sharp increases in annual total medical costs and non-drug medical costs in the 1?year post-period for patients with Stage 4 or 5 CKD (estimated glomerular filtration rate [eGFR]?≤?30?mL/min/1.73 m2) with each 1 point reduction in eGFR from 30 associated with an increase of $1,870 in all-cause total medical costs (p?<?0.0001) and $1,805 of all-cause non-drug medical costs (p?<?0.0001). Similarly, each point decline below 30?mL/min was associated annual cost increases of $1,701 for CKD-related total medical costs, $1,695 for CKD-related non-drug medical costs, $173 for diabetes-related medical costs, and $187 for diabetes-related non-drug medical costs (all p?<?0.0001).

Limitations: The investigation included only patients with medical insurance and laboratory test results, and results may not be generalizable to all T2D patients with CKD. The methodology allowed us to determine associations, not causation, and potential confounders, such as duration of diabetes, diet, exercise, or social support, could not be assessed.

Conclusions: Results indicate there are sharp and significant increases in medical costs among T2D patients with Stage 4 and 5 CKD compared to those with earlier stages of CKD.  相似文献   
979.
Aim: To assess the cost-effectiveness in Canada of atezolizumab compared with docetaxel or nivolumab for the treatment of advanced NSCLC after first-line platinum-doublet chemotherapy.

Materials and methods: A three-state partitioned-survival model was developed. Clinical inputs were obtained from the phase III OAK trial comparing atezolizumab with docetaxel in patients with advanced NSCLC who progressed after first-line platinum-doublet chemotherapy. Overall survival (OS) and progression-free survival (PFS) were extrapolated beyond the trial period using parametric models. A cure model assuming a 1% cure fraction was fitted to the OS data for atezolizumab. Outcomes for nivolumab were informed by a network meta-analysis (NMA) vs atezolizumab. Resource use and costs were informed by clinical expert opinion and published Canadian sources. Utility values were obtained from the OAK trial. The perspective of the analysis was that of the Canadian publicly-funded healthcare system. The base case time horizon was 10?years, and the discount rate was 1.5% annually for both costs and effects. Scenario analyses were performed to test the robustness of the results and all analyses were performed probabilistically.

Results: Atezolizumab demonstrated a quality-adjusted life-year (QALY) gain of 0.60 compared with docetaxel at an incremental cost of $85,073, resulting in an incremental cost-effectiveness ratio (ICER) of $142,074/QALY. Atezolizumab dominated nivolumab (regardless of dosing regimen), based on modest differences in both QALYs and costs. Docetaxel was most likely to be cost effective at willingness-to-pay (WTP) thresholds below $125,000/QALY gained, while atezolizumab was most likely to be cost effective beyond this WTP threshold. In most scenario analyses, the results remained robust to changes in parameters. A reduced time horizon and alternative approaches to the NMA had the greatest impact on cost-effectiveness results.

Conclusion: Atezolizumab represents a cost-effective therapeutic option in Canada for the treatment of patients with advanced NSCLC who progress after first-line platinum doublet chemotherapy.  相似文献   
980.
Russian agriculture is coming off a successful period under Minister Alexander Tkachev. Despite his successes, new agricultural leaders were named in May 2018 to guide agriculture during Putin’s fourth term. The article analyses the condition of and prospects for the agricultural sector during 2018–2024, using a SWOT framework (strengths, weaknesses, opportunities and threats). The analysis examines four strengths, six weaknesses, four opportunities and three threats.  相似文献   
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