<strong>Introduction:</strong> Malaria control becomes effective if countries adopt the World Health Organization & Global Malaria Programme (WHO/GMP) recommendation with includes diagnosis of malaria ...<strong>Introduction:</strong> Malaria control becomes effective if countries adopt the World Health Organization & Global Malaria Programme (WHO/GMP) recommendation with includes diagnosis of malaria cases and treatment with effective medicines, distribution of insecticide-treated nets (ITNs) and indoor residual spraying (IRS). Ownership and utilization of mosquito nets for malaria prevention is still sub-optimal with only 62% ownership of at least one mosquito net and only 37% of children using the nets. This seeks to investigate the willingness to buy and the use ITN use among caregivers of under five children attending immunization clinic in Bingham University Teaching Hospital. <strong>Methodology:</strong> A descriptive cross sectional study design carried out among 242 caregivers of all ages and sex of under-five children attending immunization clinic at Bingham University Teaching Hospital (BHUTH) in Jos North Local Government Area of Plateau State, Nigeria. A Simple Random Sampling technique was used to select respondents. <strong>Findings:</strong> Two hundred and sixteen 216 (89.3%) of the children use ITNs, majority of the children 190 (78.5%) slept under ITN the night before the interview, 226 (93.4%) owned ITNs, 156 (64.5%) got the ITNs for free while 60 (24.8%) paid for it and majority 172 (71.1%) of the children use ITN every night. Tertiary education, having much younger children (less than 3 years) and perception as a means of malaria prevention were associated with higher use of ITNs. Majority 220 (90.9%) the caregivers were willing to buy ITN and also recommend ITN to others. Caregivers who were traders and civil servants were willing to buy ITN than farmers, tertiary education, having children 1 - 3 months old, and owning 3 or more ITNs was associated with willingness to buy ITNs. <strong>Conclusion: </strong>About 90% of the children of caregivers use ITNs and over three quarters slept under ITN the night before the interview and majority use it every night. Majority the caregivers were will展开更多
The phenomena associated with the performance of newly listed companies has increased the interest of many researchers who have developed a vast literature on long-term underpricing and underperformance, which togethe...The phenomena associated with the performance of newly listed companies has increased the interest of many researchers who have developed a vast literature on long-term underpricing and underperformance, which together with hot and cold issue markets, represent the three anomalies that have always accompanied with Initial Public Offerings （IPOs）. The objective of this work is to investigate the long-run performance of IPOs of venture and non-venture-backed companies. The analysis of a sample of 102 IPOs carried out in Italy in 1998-2005 revealed that both companies （venture-backed and non-venture-backed） showed negative values, thus, confirming the phenomenon of underperformance. During the 36 months following their listing, venture-backed companies seemed to register negative and statistically significant values both with the CARsVB methodology （-93.99%） and the Buy and Hold Abnormal Returns methodology （BHARsVB -88.37%）. Venture-backed companies, unlike non- venture-backed companies, seem to be able to restrain the losses, measured by both methods, in the first 12 months （CARsB - 12.38% -20.15% CARSNNVB; BHARsVB - 10.17%; BHARsNVB - 15.51%）. During the 36 months, however, the IPOs showed negative and statistically significant values regardless of whether they were venture or non-venture-backed. The test on the difference between the average abnormal returns of the two methodologies （CAARS and BHAARs） did not produce statistically significant results. The Wealth Relative was calculated and from the results it would appear that the portfolio of venture-backed IPOs does not register ＂brilliant＂ performances. The portfolio of 102 IPOs does not seem to beat the ＂market portfolio＂. In conclusion, therefore, the phenomenon of underperformance seems to be real in our country and is documented by strongly negative and statistically significant values obtained from the samples of IPOs analyzed.展开更多
从消费者体验需求差异的角度探讨企业实施不同销售模式的最佳市场情形和时机以及提供BOPS(Buy Online and Pick up in Store)带来的影响。首先对不同销售模式下企业的最优价格与服务策略进行研究,其次分析了企业市场规模、消费者服务敏...从消费者体验需求差异的角度探讨企业实施不同销售模式的最佳市场情形和时机以及提供BOPS(Buy Online and Pick up in Store)带来的影响。首先对不同销售模式下企业的最优价格与服务策略进行研究,其次分析了企业市场规模、消费者服务敏感性对企业决策、利润及整体收益的影响。研究表明:企业是否实行BOPS取决于市场中消费者的服务敏感性,当消费者服务敏感性较高时,企业实施BOPS更为有利;在BOPS模式下,产品最优价格以及实体店内的服务水平不仅要考虑市场规模、产品成本,还需要对消费者的服务敏感性准确定位。展开更多
In this paper, we examine the best time to sell a stock at a price being as close as possible to its highest price over a finite time horizon [0, T], where the stock price is modelled by a geometric Brownian motion an...In this paper, we examine the best time to sell a stock at a price being as close as possible to its highest price over a finite time horizon [0, T], where the stock price is modelled by a geometric Brownian motion and the ＇closeness＇ is measured by the relative error of the stock price to its highest price over [0, T]. More precisely, we want to optimize the expression：V^＊=sup 0≤τ≤T E[Vτ/MT],where （Vt）t≥0 is a geometric Drownian motion with constant drift α and constant volatility σ 〉 0, Mt = max Vs 0≤a〈t is the running maximum of the stock price, and the supremum is taken over all possible stopping times 0 ≤ τ≤T adapted to the natural filtration （Ft）t≥0 of the stock price. The above problem has been considered by Shiryacv, Xu and Zhou （2008） and Du Toit and Peskir （2009）. In this paper we provide an independent proof that when α=1/ 2 σ^2 , a selling strategy is optimal if and only if it sells the stock either at the terminal time T or at the 1 2 moment when the stock price hits its maximum price so far. Besides, when α 〉1/2σ^2 , selling the stock at the terminal time T is the unique optimal selling strategy. Our approach to the problem is purely probabilistic and has been inspired by relating the notion of dominant stopping pr of a stopping time τ to the optimal stopping strategy arisen in the classical ＂Secretary Problem＂.展开更多
文摘<strong>Introduction:</strong> Malaria control becomes effective if countries adopt the World Health Organization & Global Malaria Programme (WHO/GMP) recommendation with includes diagnosis of malaria cases and treatment with effective medicines, distribution of insecticide-treated nets (ITNs) and indoor residual spraying (IRS). Ownership and utilization of mosquito nets for malaria prevention is still sub-optimal with only 62% ownership of at least one mosquito net and only 37% of children using the nets. This seeks to investigate the willingness to buy and the use ITN use among caregivers of under five children attending immunization clinic in Bingham University Teaching Hospital. <strong>Methodology:</strong> A descriptive cross sectional study design carried out among 242 caregivers of all ages and sex of under-five children attending immunization clinic at Bingham University Teaching Hospital (BHUTH) in Jos North Local Government Area of Plateau State, Nigeria. A Simple Random Sampling technique was used to select respondents. <strong>Findings:</strong> Two hundred and sixteen 216 (89.3%) of the children use ITNs, majority of the children 190 (78.5%) slept under ITN the night before the interview, 226 (93.4%) owned ITNs, 156 (64.5%) got the ITNs for free while 60 (24.8%) paid for it and majority 172 (71.1%) of the children use ITN every night. Tertiary education, having much younger children (less than 3 years) and perception as a means of malaria prevention were associated with higher use of ITNs. Majority 220 (90.9%) the caregivers were willing to buy ITN and also recommend ITN to others. Caregivers who were traders and civil servants were willing to buy ITN than farmers, tertiary education, having children 1 - 3 months old, and owning 3 or more ITNs was associated with willingness to buy ITNs. <strong>Conclusion: </strong>About 90% of the children of caregivers use ITNs and over three quarters slept under ITN the night before the interview and majority use it every night. Majority the caregivers were will
文摘The phenomena associated with the performance of newly listed companies has increased the interest of many researchers who have developed a vast literature on long-term underpricing and underperformance, which together with hot and cold issue markets, represent the three anomalies that have always accompanied with Initial Public Offerings （IPOs）. The objective of this work is to investigate the long-run performance of IPOs of venture and non-venture-backed companies. The analysis of a sample of 102 IPOs carried out in Italy in 1998-2005 revealed that both companies （venture-backed and non-venture-backed） showed negative values, thus, confirming the phenomenon of underperformance. During the 36 months following their listing, venture-backed companies seemed to register negative and statistically significant values both with the CARsVB methodology （-93.99%） and the Buy and Hold Abnormal Returns methodology （BHARsVB -88.37%）. Venture-backed companies, unlike non- venture-backed companies, seem to be able to restrain the losses, measured by both methods, in the first 12 months （CARsB - 12.38% -20.15% CARSNNVB; BHARsVB - 10.17%; BHARsNVB - 15.51%）. During the 36 months, however, the IPOs showed negative and statistically significant values regardless of whether they were venture or non-venture-backed. The test on the difference between the average abnormal returns of the two methodologies （CAARS and BHAARs） did not produce statistically significant results. The Wealth Relative was calculated and from the results it would appear that the portfolio of venture-backed IPOs does not register ＂brilliant＂ performances. The portfolio of 102 IPOs does not seem to beat the ＂market portfolio＂. In conclusion, therefore, the phenomenon of underperformance seems to be real in our country and is documented by strongly negative and statistically significant values obtained from the samples of IPOs analyzed.
文摘从消费者体验需求差异的角度探讨企业实施不同销售模式的最佳市场情形和时机以及提供BOPS(Buy Online and Pick up in Store)带来的影响。首先对不同销售模式下企业的最优价格与服务策略进行研究,其次分析了企业市场规模、消费者服务敏感性对企业决策、利润及整体收益的影响。研究表明:企业是否实行BOPS取决于市场中消费者的服务敏感性,当消费者服务敏感性较高时,企业实施BOPS更为有利;在BOPS模式下,产品最优价格以及实体店内的服务水平不仅要考虑市场规模、产品成本,还需要对消费者的服务敏感性准确定位。
基金supported by the Hong Kong RGC GRF 502909The Hong Kong Polytechnic University Internal Grant APC0D+1 种基金The Hong Kong Polytechnic University Collaborative Research Grant G-YH96supported by an internal grant of code 201109176016 from the University of Hong Kong
文摘In this paper, we examine the best time to sell a stock at a price being as close as possible to its highest price over a finite time horizon [0, T], where the stock price is modelled by a geometric Brownian motion and the ＇closeness＇ is measured by the relative error of the stock price to its highest price over [0, T]. More precisely, we want to optimize the expression：V^＊=sup 0≤τ≤T E[Vτ/MT],where （Vt）t≥0 is a geometric Drownian motion with constant drift α and constant volatility σ 〉 0, Mt = max Vs 0≤a〈t is the running maximum of the stock price, and the supremum is taken over all possible stopping times 0 ≤ τ≤T adapted to the natural filtration （Ft）t≥0 of the stock price. The above problem has been considered by Shiryacv, Xu and Zhou （2008） and Du Toit and Peskir （2009）. In this paper we provide an independent proof that when α=1/ 2 σ^2 , a selling strategy is optimal if and only if it sells the stock either at the terminal time T or at the 1 2 moment when the stock price hits its maximum price so far. Besides, when α 〉1/2σ^2 , selling the stock at the terminal time T is the unique optimal selling strategy. Our approach to the problem is purely probabilistic and has been inspired by relating the notion of dominant stopping pr of a stopping time τ to the optimal stopping strategy arisen in the classical ＂Secretary Problem＂.
