Universal Point Estimation, with Applications in Economics, Business and Decision Sciences

Estimation is used widely in numerous disciplines, including Mathematics, Statistics, Economics, Business, and Decision Sciences, among others. Estimation is a process for determining an approximation, which is a value that can be used for a number of purposes, even if input data are sufficient, incomplete, missing or unsecure. In practice, estimation relates to “using the value of a statistic inferred from a sample to estimate the value of a corresponding population parameterâ€. Estimation is usually separated into two categories, namely point estimation and interval estimation. The main purpose of this paper is to present a universal approach to the theory and practice of three methods in statistical inference to obtain point estimates, namely the moment, maximum likelihood, and Bayesian methods. The paper also discusses the advantages and disadvantages of the three universal approaches in practical applications in Economics, Business and Decision Sciences

Factors Affecting E-Commerce Customer Satisfaction in Hanoi, Vietnam

The escalating ubiquity and cost-effectiveness of internet facilities have precipitated a notable surge in the adoption of e-commerce among Vietnamese inhabitants, particularly those residing in urban areas. This research endeavours to enhance comprehension of factors affecting e-commerce customer satisfaction in Hanoi, Vietnam. A quantitative survey of this research was conducted in which online questionnaires were distributed to 382 respondents through social media. The amassed data underwent meticulous analysis utilizing Microsoft Excel. The findings of this investigation underscore that information quality, system quality, service quality and price simultaneously influence e-commerce customer satisfaction. Keywords: factors, e-commerce customers, satisfaction DOI: 10.7176/EJBM/16-2-03 Publication date:March 31st 202

Biocontrol of Alternaria alternata YZU, a causal of stem end rot disease on pitaya, with soil phosphate solubilizing bacteria

Stem end rot is the most destructive disease caused by Alternaria alternata YZU in pitaya-growing regions of Vietnam. This study was conducted to characterize antagonistic phosphate-solubilizing bacteria (PSB) from rhizosphere soil for their biocontrol activities against A. alternata YZU and evaluate the effect of temperature, pH, and water activity on that antagonism. Among seven PSB isolated from 45 rhizosphere soil samples, PSB31 (identified as Bacillus sp. strain IMAU61039, Accession number: MF803700.1) exhibited the highest antagonistic activity against A. alternata YZU with an average inhibition diameter of 0.65 ± 0.05 cm. The results also show that the strain PSB31 controlled the mycelial growth of A. alternata YZU by secreting antifungal metabolites. The most potent inhibitory activity was identified under in vitro conditions of 25 °C, pH 7, and aw 1. The isolated PSB31 could be a potential biological control agent against A. alternata YZU

INFLUENCING FACTORS TO LOGISTICS CENTRE FORMATION – A STUDY OF VIETNAM-BASED LOGISTICS SECTOR

Purpose of the study: The paper tries to model dynamic interactions of factors that contribute to the logistics center building. Conducting the desk review and expert consultation, the causality of the factors is systemized in a form of Causal Loop Diagram using the System Dynamics approach. Methodology: System Dynamics (SD) is an approach for studying interlinked behaviors within a system and reflects the interactions of feedback loops. Compared to other approaches, SD demonstrates the real world by using factors and stocks for components and feedback loops for inter-relationships among them. SD model qualitatively illustrates the causal relationship among factors that influence the building of the logistics center. Main Findings: A combination of four different sub-systems, using a questionnaire survey conducted with logistics service users and providers to sort out the high scored factors. Besides, the survey also helps to study the practical conditions and characteristics in showing the demand, the trend, and the development of logistics centers in Vietnam. Applications of this study: Logistics centers (LCs) can be considered as a depot for vehicles where drivers and managers of vehicles are supposed to maintain, repair vehicles, and adjust vehicle operation schedules. Novelty/Originality of this study: As defined by the scope of the project, the SD model provides a qualitative demonstration of the interaction among factors. The built model gives a systematic insight into how factors link to each other

Neuromuscular Blockade Agents Reversal with Sugammadex Compared to Neostigmine in the Living Kidney Donors

Backround: The reversation of NMBA (neuromuscular blocking agents) prevents numerous postoperative complications, increases quality of recovery and decreases the time, expenditure spending in hospital. The choice of medicine used to reverse NMBA depends  considered as a key fators to gain the best outcome and to avoid the side effects. Aim: To evaluate the postoperative effect on muscle relaxation reversal and side effects of sugammadex 2 mg/kg versus the combination of  neostigmine and atropine sulfate in the living kidney donors. MethodS: A randomised controlled trial on 70 patients undergoing living kidney donation surgery were allocated to 2 groups. Patients in group I (SUGA) were reversed with sugammadex 2 mg/kg and in group II (NEO/ATR) with the combination of neostigmine and atropine sulfat. Results: With 35 patients in each group, the study results showed that after 3 mintutes of reversal patients reaching TOF value ≥ 0.9 in group SUGA is 91.4%, after 5 minutes 100% of patients in group SUGA reached TOF value ≥ 0.9 . In group NEO/ATR after 3 minutes 28.6% patients reached TOF ≥ 0.9 and 40% patients reached TOF≥ 0.9 after 5 minutes. The difference in percentage of patients reaching TOF ≥ 0.9 after 3 minutes, 5 minutes of reversal between two groups is significant (p<0.05). After 10 minutes, 100% patients in both group got TOF ≥ 0.9. Time to exutubation of group SUGA was 249.43 ± 81.75 seconds and it was 456.29 ± 146.45 seconds in group NEO/ATR. Nausea, bradycardia, and increased phlegm production in group NEO/ATR was 22.9%; 28.5%; 25.7% respectively; while those side effects were not met in group SUGA, the difference was significant (p<0.05). Conclusion: The muscle relaxation reversal effect of sugammadex was faster than that of neostigmine, the duration TOF ≥ 0.9 and the time to extubation was significantly faster. Sugammadex did not cause hemodynamic changes before and after muscle relaxation reversal, neostigmine resulted in the bradycardia, increased phlegm secreting and other side effects. The renal function after 24 hours postoperatively of two groups was similar

HMU fluorinze mouthwash enhances enamel remineralization: An in vitro study

BACKGROUND: Fluoride therapy has long been used extensively to prevent dental caries. Fluoride appears in variety of dental care products such as mouthrinse, dentifrice, gel, etc. HMU fluorinze is the first mouthwash containing fluoride in Vietnam. AIM: This research was conducted to evaluate the efficacy of HMU Fluorinze mouthwash on remineralizing enamel in laboratory conditions. METHODS: 20 third molars teeth were cleaned and covered with nail polish , except for a 3x3 mm square on their buccal surfaces. These teeth went through two steps: demineralization using Coke and remineralization for 20 days: 1) using standard calcifying solution (control group) and 2) using standard calcifying solution + HMU Fluorinze mouthwash 2 times/day (experimental group). The mineralization index of enamel structure after demineralization and remineralization was assessed by DIAGNOdent pen 2190. RESULTS: The mineralization indexes of the control group and experimental group at baseline were 3.65 ± 0.76 and 3.35 ± 0.64, after demineralization were in turn of 21.78 ± 4.48 and 20.25 ± 2.26; and after remineralization were 6.30 ± 1.03 and 3.90 ± 1.24. The different figures  between the two groups after remineralization shows statistical significance (p<0.01). Group B using HMU fluorinze mouthwash after 20 days did not differ from the original results (p = 0.272), in contrast with the control group (p<0.01). CONCLUSIONS: HMU fluorinze mouthwash has better mineralization effect than standard calcifying solution

Socializing One Health: an innovative strategy to investigate social and behavioral risks of emerging viral threats

In an effort to strengthen global capacity to prevent, detect, and control infectious diseases in animals and people, the United States Agency for International Development’s (USAID) Emerging Pandemic Threats (EPT) PREDICT project funded development of regional, national, and local One Health capacities for early disease detection, rapid response, disease control, and risk reduction. From the outset, the EPT approach was inclusive of social science research methods designed to understand the contexts and behaviors of communities living and working at human-animal-environment interfaces considered high-risk for virus emergence. Using qualitative and quantitative approaches, PREDICT behavioral research aimed to identify and assess a range of socio-cultural behaviors that could be influential in zoonotic disease emergence, amplification, and transmission. This broad approach to behavioral risk characterization enabled us to identify and characterize human activities that could be linked to the transmission dynamics of new and emerging viruses. This paper provides a discussion of implementation of a social science approach within a zoonotic surveillance framework. We conducted in-depth ethnographic interviews and focus groups to better understand the individual- and community-level knowledge, attitudes, and practices that potentially put participants at risk for zoonotic disease transmission from the animals they live and work with, across 6 interface domains. When we asked highly-exposed individuals (ie. bushmeat hunters, wildlife or guano farmers) about the risk they perceived in their occupational activities, most did not perceive it to be risky, whether because it was normalized by years (or generations) of doing such an activity, or due to lack of information about potential risks. Integrating the social sciences allows investigations of the specific human activities that are hypothesized to drive disease emergence, amplification, and transmission, in order to better substantiate behavioral disease drivers, along with the social dimensions of infection and transmission dynamics. Understanding these dynamics is critical to achieving health security--the protection from threats to health-- which requires investments in both collective and individual health security. Involving behavioral sciences into zoonotic disease surveillance allowed us to push toward fuller community integration and engagement and toward dialogue and implementation of recommendations for disease prevention and improved health security

Impact of earning management and business strategy on financial distress risk of Vietnamese companies

AbstractMany Vietnamese companies’ net incomes have increased significantly in recent years as a result of creative competitive strategies, but many of them are being forced to delist due to persistent losses and manipulative earnings. In this paper, we are the first to investigate the simultaneous impact of business strategy and earning management on the risk of financial distress. The sample for the study includes information from 601 companies that are listed on the Ho Chi Minh City Stock Exchange between 2010 and 2021. The finding indicates that there is a high risk of financial distress for companies that manipulate earnings by increasing discretionary accruals value. However, if firms manipulate earnings through real operations, the risk of financial distress is reduced. Firms will see a significant improvement in their financial performance if they adopt a key differentiation or low-cost leadership strategy that gives them a competitive advantage in the same industry. The firm size, leverage, firm loss, and liquidity ratio are also the main factors that influence financial distress risk. These results are robust by using alternative proxies of financial distress risk (O and ZM score) to control for potential endogeneity

Is the market biased in M&A, dividend payment, and share repurchase events?

Companies with excess capital can opt to: pay dividends to shareholders, buy back treasury shares for short-term shareholder benefits, or pursue M&A investments for long-term shareholder returns. Using difference in differences approach of event research methods combined with unique manually collected data sets, this paper investigates the market bias for three events: M&A, share repurchase, and dividend payment. The results show that information was leaked to the outside 1 day before it was officially announced at all events. When observing the company's performance 3 years after the event announcement, we also find that the market reaction is biased in M&A and stock dividend payment events, but accurate in the cash dividend payment and share repurchases. In addition, the market has the strongest and longest reaction to the news of the company buying back shares; has the weakest reaction to the stock dividend payment; has the shortest reaction to cash dividend payment; has a negative reaction to the acquisition company's stock, and has a positive reaction to the target company's stock. Our research has provided empirical evidence on the market response to published information, and supports CEOs make the most accurate choices when the company has an excess cash flow

Factors Affecting E-Commerce Customer Satisfaction in Hanoi, Vietnam

The escalating ubiquity and cost-effectiveness of internet facilities have precipitated a notable surge in the adoption of e-commerce among Vietnamese inhabitants, particularly those residing in urban areas. This research endeavours to enhance comprehension of factors affecting e-commerce customer satisfaction in Hanoi, Vietnam. A quantitative survey of this research was conducted in which online questionnaires were distributed to 382 respondents through social media. The amassed data underwent meticulous analysis utilizing Microsoft Excel. The findings of this investigation underscore that information quality, system quality, service quality and price simultaneously influence e-commerce customer satisfaction. Keywords: factors, e-commerce customers, satisfaction DOI: 10.7176/JESD/15-5-01 Publication date: April 30th 202