一种机载地面侦察雷达多机动目标跟踪方法

加拿大经济学家巴伯(C.L.Barber)提出的有效保护率概念是对整个产业征税后实际保护程度的一个有效分析工具。但一些不符合现实的假设条件限制了有效保护理论的适用范围。一些著作也就这方面的问题作过探讨,本文在综合一些学者观点的基础上逐步放宽了其所假设的限制条件,使这一理论更加完善,更具现实指导意义。并在此基础上对中国关税结构的优化问题进行简要的分析。     

Investment and dynamic DEA

A dynamic version of data envelopment analysis (DEA) is developed in the present paper. Our model introduces investment in traditional DEA and imposes intertemporal cost minimization. Adding an intertemporal adjustment constraint into the cost minimization problem, we derive the relation between the DEA variables of the variable cost function and those of the primary production frontiers’ coefficients. The augmented DEA model can be solved using standard linear programming. This dynamic framework enables computing the production frontiers, measuring the productive efficiencies and evaluating the potential economies all in the presence of adjustment costs.

The cost-effectiveness of delayed-release dimethyl fumarate for the treatment of relapsing-remitting multiple sclerosis in Canada

Background: Multiple sclerosis (MS) causes significant disability and diminished quality-of-life. Delayed-release dimethyl fumarate (DMF; also known as gastro-resistant DMF) is a new oral treatment for relapsing-remitting MS (RRMS) approved in the US, Australia, Canada, and Europe. Objectives: A cost-effectiveness model was developed to compare the health economic impact of DMF against other disease-modifying therapies (DMTs) as first-line RRMS treatment from a Canadian Ministry of Health perspective. Methods: A Markov cohort model was developed to simulate patients’ progression through health states based on the Kurtzke Expanded Disability Status Scale (EDSS) over a life-time horizon. Patients entered the model based on a distribution of baseline EDSS scores, from which they could progress to higher or regress to lower EDSS state, or remain in the same state. Relapses could occur at any EDSS score. Results from a mixed-treatment comparison were used to inform model inputs for disease progression and relapse rates per treatment. Costs included direct medical costs stratified by EDSS score. Utilities were accrued based on time spent in each EDSS state. Results: Compared with glatiramer acetate, DMF yielded 0.528 incremental quality-adjusted life-years (QALYs) at an incremental cost of $23 338 Canadian dollars (CAD), resulting in an incremental cost-effectiveness ratio (ICER) of CAD $44 118/QALY. The ICER for DMF compared with Rebif 44?mcg was CAD $10 672. Results were consistent across a wide range of one-way and probabilistic sensitivity analyses. Conclusions: Based on traditional cost-effectiveness thresholds in Canada (CAD $50 000–60 000), DMF can be considered a cost-effective option compared to other first-line DMTs.     

The role of multiple values in developing management accounting practices in hybrid organisations

The aim of this study is to investigate how multiple values in non-profit hybrid organisations influence the adoption of management accounting practices. The empirical analysis centres on hybrid organisations established as co-production and co-management initiatives in social care. Pragmatic constructivism, centred on the role of values, informs the empirical analysis. This research shows that management accounting practices can develop without conflicts when only some actors are interested in management and their values predominate, despite the coexistence of multiple and conflicting values. However, in this situation, where conflicts are eliminated, the validity of accounting is compromised, as it does not represent all values. The evidence of this lack of validity is clear when considering the poor development of management accounting practices and the inability to develop some relevant measures, such as outcome measures. When only some values predominate, the opportunity provided by the multiplicity of values to the development of management accounting practices is lost, and possible inefficiencies may emerge. The use of pragmatic constructivism shows that this lack of validity, determined by the non-integration of values, would be reduced by increasing the discussion among conflicting actors’ values. Findings suggest that the presence of conflicting values, that at first glance may be interpreted as an impediment, would, on the contrary, be useful to support accounting validity, when stimulating discussion. In this respect, conflicting values should work alongside communication, to include dimensions of reality.     

Criteria selection and multi-objective optimization of aircraft landing problem

Inspired by the similarities of the aircraft landing problem (ALP) and the single machine scheduling problem, we propose a criteria selection method that has been used successfully in the single machine scheduling problem to determine appropriate objective functions of ALP. First, for four different types of criteria—min-max, min-sum, completion time related, and due-dates related criteria—their corresponding physical meanings in ALP are elaborated. Then, a criteria selection method is proposed to determine several appropriate criteria, which are taken as the multi-objective while modeling ALP. Different solution algorithms, including Imperialist Competitive Algorithm (ICA), are adopted to solve the multi-objective ALP. Finally, the performance of the proposed model and method are evaluated using a set of benchmark instances. The computational results demonstrate the efficiency of our approach for solving ALP, which can simultaneously improve punctual performance, enhance runway utilization, reduce air traffic controller workload, and maintain equity among airlines.     

Treatment experience,burden and unmet needs (TRIBUNE) in MS study: results from Turkey

Abstract

Objective:

To estimate the economic burden of multiple sclerosis (MS) in Turkey, including the relapses and disease severity, and to evaluate the quality-of-life of MS patients.

Methods:

The Treatment Experience, Burden and Unmet Needs (TRIBUNE) study was a multi-national, cross-sectional, retrospective, burden-of-illness survey. Total costs were calculated using unit costs derived from price lists or published literature, where relevant, and inflated to 2011 TL prices.

Results:

A total of 295 MS patients (74% females) were included in the analysis. The population had a mean age of 36 years; 73% had the relapsing–remitting form. Mean Expanded Disability Status Scale (EDSS) score was 2.2. Twenty-two per cent of the MS patients required hospitalization in the past year and spent an average of 29.2 days/year in hospital. These values were 43% and 5.6 days for the outpatients, respectively. Total cost per patient/year was 18,700 TL (Turkish Lira). Total costs for patients with mild, moderate, and severe disability were 15,418 TL, 26,002 TL, and 44,208 TL per patient/year, respectively. The mean EuroQol 5D scores in the same groups were 0.73, 0.52, and 0.05, respectively.

Conclusions:

Multiple sclerosis imposes a significant economic burden on patients and society in Turkey.     

Cost-effectiveness of fingolimod versus interferon beta-1a for relapsing remitting multiple sclerosis in the United States

Abstract

Objective:

Fingolimod has been shown to be more efficacious than interferon (IFN) beta-1a, but at a higher drug acquisition cost. The aim of this study was to assess the cost-effectiveness of fingolimod compared to IFN beta-1a in patients diagnosed with relapsing-remitting multiple sclerosis (RRMS) in the US.

Methods:

A Markov model comparing fingolimod to intramuscular IFN beta-1a using a US societal perspective and a 10-year time horizon was developed. A cohort of 37-year-old patients with RRMS and a Kurtzke Expanded Disability Status Scale score of 0–2.5 were assumed. Data sources included the Trial Assessing Injectable Interferon vs FTY720 Oral in Relapsing–Remitting Multiple Sclerosis (TRANSFORMS) and other published studies of MS. Outcomes included costs in 2011 US dollars, quality-adjusted life years (QALYs), number of relapses avoided, and incremental cost-effectiveness ratios (ICERs).

Results:

Compared to IFN beta-1a, fingolimod was associated with fewer relapses (0.41 vs 0.73 per patient per year) and more QALYs gained (6.7663 vs 5.9503), but at a higher cost ($565,598 vs $505,234). This resulted in an ICER of $73,975 per QALY. Results were most sensitive to changes in drug costs and the disutility of receiving IFN beta-1a. Monte Carlo simulation demonstrated fingolimod was cost-effective in 35% and 70% of 10,000 iterations, assuming willingness-to-pay thresholds of $50,000 and $100,000 per QALY, respectively.

Limitations:

Event rates were primarily derived from a single randomized clinical trial with 1-year duration of follow-up and extrapolated to a 10-year time horizon. Comparison was made to only one disease-modifying drug—intramuscular IFN beta-1a.

Conclusion:

Fingolimod use is not likely to be cost-effective compared to IFN beta-1a unless fingolimod cost falls below $3476 per month or a higher than normal willingness-to-pay threshold is accepted by decision-makers.     

High frequency trading and the new market makers

This paper characterizes the trading strategy of a large high frequency trader (HFT). The HFT incurs a loss on its inventory but earns a profit on the bid–ask spread. Sharpe ratio calculations show that performance is very sensitive to cost of capital assumptions. The HFT employs a cross-market strategy as half of its trades materialize on the incumbent market and the other half on a small, high-growth entrant market. Its trade participation rate in these markets is 8.1% and 64.4%, respectively. In both markets, four out of five of its trades are passive i.e., its price quote was consumed by others.     

Probability of multiple crossings and pricing of double barrier options

This paper derives pricing formulas of standard double barrier option, generalized window double barrier option and chained option. Our method is based on probabilitic approach. We derive the probability of multiple crossings of curved barriers for Brownian motion with drift, by repeatedly applying the Girsanov theorem and the reflection principle. The price of a standard double barrier option is presented as an infinite sum that converges very rapidly. Although the price formula of standard double barrier option is the same with Kunitomo and Ikeda (1992), our method gives an intuitive interpretation for each term in the infinite series. From the intuitive interpretation we present the way how to approximate the infinite sum in the pricing formula and an error bound for the given approximation. Guillaume (2003) and Jun and Ku (2013) assumed that barriers are constant to price barrier options. We extend constant barriers of window double barrier option and chained option to curved barriers. By employing multiple crossing probabilities and previous skills we derive closed formula for prices of 16 types of the generalized chained option. Based on our analytic formulas we compute Greeks of chained options directly.     

Information asymmetry,market segmentation,and cross-listing: Implications for event study methodology

This paper connects three subjects related to international financial markets – (i) information asymmetry, (ii) market segmentation, and (iii) cross-listings – and highlights their implication for event study methodology. When firms list equities on more than one exchange, and the exchanges are characterized by different information sets, a problem arises as to which exchange(s) to include in the event study sample. If market segmentation impedes the arbitrage of these multiple responses, then the use of a single listing (for a firm that is cross-listed) can yield abnormal return estimates that are biased. In such circumstances, using returns from all the markets in which a firm's securities are listed not only increases the sample size (often an important consideration when undertaking event studies in emerging markets), but also enables full-information abnormal return estimates to be obtained. What is required is a method that extracts the independent information from each listing while counting the common information only once. In this paper, we develop an estimation procedure that achieves these twin objectives. We then apply our approach to an event study of Chinese overseas mergers and acquisitions, and compare results from alternative samples and estimators. We demonstrate that including return data from cross-listings of the same firm can result in substantially different conclusions.