• Title/Summary/Keyword: Risk Estimation

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Direction for the management of air pollutants based on health risk in Korea (위해성을 고려한 대기오염물질의 관리 방향)

  • Kim, Young Ju;Kim, Yong Pyo
    • Particle and aerosol research
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    • v.13 no.2
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    • pp.43-52
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    • 2017
  • Policy direction for the management of air quality in Korea has been on the reduction of the average concentrations of the criteria air pollutants such as sulfur dioxide and fine particles. However, recently, risk based management of air pollutants becomes an important issue. In this study, to develop an effective air quality management policy direction in Korea, (1) the fourth Multiple Air Toxics Exposure Study (MATES IV) carried out in the South Coast Air Quality Management District (SQAQMD) in the USA is reviewed and (2) the results are compared with in these in Seoul and (3) policy directions are suggested. It was found that (1) systematic integrated study comprising of measurement, modeling, emission inventory estimation, and risk assessment was essential to estimate the health risk of air pollutants reliably, (2) cancer risk of diesel particle was dominant over other air pollutants, and (3) health risk based emissions were different from amount based emissions. It was suggested that (1) reducing the exposure from hot spots might important to reduce health risk from air pollutants and (2) an integrated air quality management administration system is important for the efficient management of air pollution.

Risk Factors for Falls in Tertiary Hospital Inpatients: A Survival Analysis (상급종합병원 입원환자의 낙상 위험요인: 생존분석으로)

  • Cho, Young Shin;Lee, Young Ock;Youn, Young Sun
    • Journal of Korean Critical Care Nursing
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    • v.12 no.1
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    • pp.57-70
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    • 2019
  • Purpose : The purpose of this study was to identify the risk factors for falls in tertiary hospital inpatients and to suggest data for developing a nursing intervention program for preventing falls. Methods: Data were collected between January 1, 2017, to December 31, 2017. Kaplan-Meier estimation was used to measure the survival rate, and the log-rank test was used for the differences between the fall group and the non-fall group. The Cox proportional hazards model was used to identify the risk factors for falls. Results: The incidence rate of falls for the inpatients was 1.2 cases per 1,000 days of hospitalization. The risk factors for falls were more likely to be found among those who were aged ${\geq}81$, had not undergone surgery, had poor joint motion, had unsteady gait, needed help or supervision, used assistive devices, had comorbidity, and took at least two drugs. Conclusion: For the inpatients, the risk factors for falls included age, surgery, comorbidity, medication that could change mobility, joint motion, and use of patient care equipment. It is necessary to give special attention to inpatients who have any of these risk factors and to develop a falls risk assessment tool.

A Study on the Variation in the Risk Probability of Runway Strips due to the Runway Displaced Threshold (활주로시단이설에 따른 착륙대 위험발생빈도 변화 연구)

  • Kim, DoHyun;Chang, Hyoseok
    • Journal of the Korean Society for Aviation and Aeronautics
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    • v.29 no.4
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    • pp.45-51
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    • 2021
  • A runway safety area (RSA) is defined as the surface surrounding the runway prepared or suitable for reducing the risk of damage to airplanes in the event of an undershoot, overshoot, or excursion from the runway. The Runway Stripe is a defined area including the runway stopway, if provided, intended firstly to reduce the risk of damage to aircraft running off a runway, and secondly, to protect aircraft flying over it during takeoff or landing operations. This study used 2 RSA analysis models; RSARA and LRSARA. The analysis utilizes historical data from the specific airport and allows to take into consideration specific operational conditions to which movements are subject, as well as the actual or planned RSA conditions in terms of dimensions, configuration, and boundaries defined by existing obstacles. This study applied the RSA and LRSA risk assessment models to a domestic airport that do not meet the criteria required by standards for aerodrome physical characteristics. The airport is considering a method to secure the runway strip standard through the displaced threshold. This study intends to confirm through quantitative risk estimation whether meeting facility standards through the runway displaced threshold leads to a positive change in risk mitigation.

The Impact of Geopolitical Risk on Financial Conditions of Emerging Economies

  • BAJAJ, Namarta Kumari;AZIZ, Tariq;KUMARI, Sonia;ALENEZI, Marim;MATHKUR, Naif Mansour
    • The Journal of Asian Finance, Economics and Business
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    • v.10 no.1
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    • pp.133-143
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    • 2023
  • The detrimental impacts of financial instability on the world economy during the financial crisis highlighted the requirement to understand the existing financial circumstances. Stability and developments in financial conditions are important for economic prosperity. This study analyses the impact of geopolitical risk on the economic conditions of some specific emerging economies using monthly data from January 1999 to September 2016 by applying a fixed-effects panel data model. The estimation results demonstrated that geopolitical risk has a significant, negative impact on financial conditions. It shows geopolitical risk could be seen as a key factor that contributes towards financial conditions. Further, it implies that negative shocks of high geopolitical risk experienced by emerging economies are one of the primary reasons for the financial conditions' deterioration. The findings provide important insights for governments, policymakers, and investors. For instance, governments and politicians should refrain from expressing or producing tension, economic discomfort, or news that is likely to increase a high geopolitical risk. Maintaining a close eye on geopolitical risk and its sources may also help to stabilize financial conditions and develop a well-functioning financial system. As a result, investors would be better informed about an economy's economic and financial conditions, allowing them to diversify their international portfolios and devise investing strategies during uncertain economic times.

An Experimental Study on the Prospect Theory (전망이론에 관한 실험연구)

  • Guahk, Seyoung
    • Journal of Digital Convergence
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    • v.15 no.11
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    • pp.107-112
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    • 2017
  • This paper performed an experimental study to test the validity of the prospect theory proposed by Tversky and Kahneman as an alternative to the expected utility theory. 115 college students attended the hypothetical games to choose one of two lotteries, one is safe option while the other one is risky. The risky options were set up to have low, medium or high probability of payoffs or losses. The amount of payoffs and losses of the lotteries was either large or small. Maximum likelihood estimation of the hypothetical games have shown that in case of high probability of positive payoffs the respondents were risk averse and when the probability of positive payoffs were small the respondents were risk loving. when the possibility of loss is high they were risk loving, while the probability is of loss is low the respondents were found to be risk averse. When the probability of risky options were medium the results were significant statistically in case of only losses. The amount of positive payoff or losses does not affect the results. Overall the results of this experiments support the prospect theory more than those of Laury & Holts (2008).

FAIR-Based Loss Measurement Caused by Personal Information Breach of a Company (FAIR를 통한 개인정보 유출에 따른 기업의 손해금액 산출에 대한 연구)

  • Kim, Jeong-Gyu;Lee, Kyung-Ho
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.27 no.1
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    • pp.129-145
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    • 2017
  • This study proposes a methodology to estimate the financial damages by personal information breach of a company and to analyse risk systematically through a case study of a company which experiences private information breach. Using FAIR(Factor Analysis of Information Risk) model, estimate the loss amount and to analyse risk objectively of a company by personal information breach. This study estimates adequacy and importance of corresponding factors applying AHP(Analytic Hierarchy Process) on each factors for assessing loss amount. By adopting proposed methodology in this study, the person in charge of actual work can assess and prove the loss amount though the latest risk estimation methodology. In addition, the person in charge can select the proper parameters for the corresponding company and can obtain the objective quantitative estimation. Hence it can be reported to the management by accurately assessing loss amount caused by personal information breach.

A comparison study on the estimation of the relative risk for the unemployed rate in small area (소지역의 실업률에 대한 상대위험도의 추정에 관한 비교연구)

  • Park, Jong-Tae
    • Journal of the Korean Data and Information Science Society
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    • v.20 no.2
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    • pp.349-356
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    • 2009
  • In this study, we suggest the estimation method of the relative risk for the unemployment statistics of a small area such as si, gun, gu in Korea. The considered method are the usual pooled estimator, weighted estimator with the inverse of log-variance as weights, and the Jackknife estimator. And we compare with the efficiency of the three estimators by estimating the bias and mean square errors using real data from the 2002 Economically Active Population Survey of Gyeonggi-do. We compute the unemployed rate of male and female in small areas, and then estimate the common relative risk for the unemployed rate between male and female. Also, the stability and reliability of the three estimators for the common relative risk was evaluated using the RB(relative bias) and the RRMSE(relative root mean square error) of these estimators. Finally, the Jackknife estimator turned out to be much more efficient than the other estimators.

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Meta-analysis of Associations between Interleukin-17 Gene Polymorphisms and Risk of Gastric Cancer

  • Yu, Hui;Sun, Si;Liu, Fang;Xu, Qing-Hua
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.20
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    • pp.8709-8713
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    • 2014
  • Background: Previous studies have indicated that single nucleotide polymorphisms (SNPs) of the interleukin-17 (IL-17) gene are associated with an increased risk of gastric cancer. However, the findings were inconsistent. Materials and Methods: To provide a more reliable estimation of the association between SNPs in the IL-17 gene and the susceptibility to gastric cancer, we searched PubMed, CNKI, and Wan Fang databases and selected finally six studies covering 2,366 cases and 3,205 controls to perform a meta-analysis. Results: Statistical analyses showed that an rs2275913 polymorphism within the IL-17A gene was significantly associated with an increased risk of gastric cancer using a generalized odds ratio (ORG, a model-free approach). Moreover, we also found that the 'A' allele carriers of IL-17A rs2275913 had a significant link with clinicopathological features. However, no significant positive signals were observed in the association analysis of the rs3748067 and rs763780 polymorphisms with the risk of gastric cancer in IL-17A and IL-17F, respectively. Conclusions: Despite some limitations, the present meta-analysis provided a more precise estimation of the relationship between the IL-17 gene SNPs and gastric cancer risk compared with individual studies.

Distribution fitting for the rate of return and value at risk (수익률 분포의 적합과 리스크값 추정)

  • Hong, Chong-Sun;Kwon, Tae-Wan
    • Journal of the Korean Data and Information Science Society
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    • v.21 no.2
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    • pp.219-229
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    • 2010
  • There have been many researches on the risk management due to rapid increase of various risk factors for financial assets. Aa a method for comprehensive risk management, Value at Risk (VaR) is developed. For estimation of VaR, it is important task to solve the problem of asymmetric distribution of the return rate with heavy tail. Most real distributions of the return rate have high positive kurtosis and low negative skewness. In this paper, some alternative distributions are used to be fitted to real distributions of the return rate of financial asset. And estimates of VaR obtained by using these fitting distributions are compared with those obtained from real distribution. It is found that normal mixture distribution is the most fitted where its skewness and kurtosis of practical distribution are close to real ones, and the VaR estimation using normal mixture distribution is more accurate than any others using other distributions including normal distribution.