• Title/Summary/Keyword: significance probability

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The Use of Propensity Score Matching for Evaluation of the Effects of Nursing Interventions (Propensity Score Matching 방법을 이용한 간호중재 효과 평가)

  • Lee, Suk-Jeong;Yoo, Ji-Soo;Shin, Mi-Kyung;Park, Chang-Gi;Lee, Hyun-Chul;Choi, Eun-Jin
    • Journal of Korean Academy of Nursing
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    • v.37 no.3
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    • pp.414-421
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    • 2007
  • Background: Nursing intervention studies often suffer from a selection bias introduced by failure of random assignment. Evaluation with selection bias could under or over-estimate any intervention's effects. PS matching (PSM) can reduce a selection bias through matching similar Propensity Scores (PS). PS is defined as the conditional probability of being treated given the individual's covariates and it can be reused to balance the covariates of two groups. Purpose: This study was done to assess the significance of PSM as an alternative evaluation method of nursing interventions. Method: An intervention study for patients with some baseline individual characteristic differences between two groups was used for this demonstration. The result of a t-test with PSM was compared with a t-test without matching. Results: The level of HbA1c at 12 months after baseline was different between the two groups in terms of matching or not. Conclusion: This study demonstrated the effects of a quasi-random assignment. Evaluation using PSM can reduce a selection bias impact that affects the result of the nursing intervention. Analyzing nursing research more objectively to reduce selection bias using PSM is needed.

Statistical investigation on size distribution of suspended cohesive sediment (점착성 부유사의 입도분포형 검증)

  • Park, Byeoungeun;Byun, Jisun;Son, Minwoo
    • Journal of Korea Water Resources Association
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    • v.53 no.10
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    • pp.917-928
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    • 2020
  • The purpose of this study is to find the appropriate probability distribution representing the size distribution of suspended cohesive sediment. Based on goodness-of-fit test for a significance level of 5% using the Kolmogorov-Smirnov test, it is found that the floc size distributions measured in laboratory experiment and field study show different results. In the case of sample data collected from field experiments, the Gamma distribution is the best fitting form. In the case of laboratory experiment results, the sample data shows the positively-skewed distribution and the GEV distribution is the best fitted. The lognormal distribution, which is generally assumed to be a floc size distribution, is not suitable for both field and laboratory results. By using 3-parameter lognormal distribution, it is shown that similar size distribution with floc size distribution can be simulated.

Regional Drought Frequency Analysis of Monthly Rainfall Data by the Method of L-Moments (L-Moment법을 이용한 월 강우량 자료의 지역가뭄빈도 해석)

  • Yun, Yong-Nam;Park, Mu-Jong
    • Journal of Korea Water Resources Association
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    • v.30 no.1
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    • pp.55-62
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    • 1997
  • To quantitatively investigate the nationwide drought characteristics and to comparatively evaluate the 1994-1995 drought with several past droughts of significant magnitude regional frequency analysis is made for the meteorological stations in each of the 47 subbasins covering the whole nation. With monthly precipitation data for the period of records at the stations in each subbasin low precipitation data series of various durations are formulated with the running totals of monthly data and fitted to probability distributions. The method of L-method of L-moments is used to determine the unbiased parameters of each distribution, and using the best-fit distribution for each subbasin the low precipitations of various durations with return periods of 5, 10, 20, 30, and 50 years are estimated. The drought frequency maps are drawn with the low drought frequency analysis the drought of 1994-1995 is evaluated in its severity and areal extent in comparison with four other past drought of significance. The current practice of safety standards for the design of impounding facilities is also evaluated with reference to the recurrence interval of the severe drought, and a recommendation is made for the future design standard.

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A Clinical Study of Moxibustion Therapy's Effect on Functional Recovery in Hemiplegia on Stroke (중풍환자의 구(灸)치료에 따른 기능회복도에 관한 임상연구)

  • Lee, Sang-Hee;Kim, Jae-Kyu;Son, Yeon-Hui;Jeong, Hyun-Yun;Kim, Jung-Hoon;Kwon, Jung-Nam;Kim, Young-Kyun
    • The Journal of Internal Korean Medicine
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    • v.29 no.1
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    • pp.278-284
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    • 2008
  • Objective : The purpose of this clinical study was to investigate the effects of moxibustion on functional recovery in stroke patients. Methods : Forty two stroke patients were randomized into either the standard physiotherapy treatment combined with moxibustion group or a control group with standard physiotherapy alone. They were 8 weeks from onset to the start of this study. Moxibustion was applied at 合谷(LI14), 外關(TE5), 曲池(LI11), 太衝(LIV3), 懸鍾(絶骨,G39), 足三里(S36) in hemiplegic upper and lower extremity, once a day for 6 weeks. The effect of treatment on functional recovery was assessed using the Functional Independence Measure scale. Statistical significance was achieved if the probability was less than 5%(p<0.05). Result : These 2 groups had comparable clinical characteristics; sex, age, lesion, and pre-treatment FIM score. After 6 weeks, patients in the moxibustion group performed better on FIM. The differences were significant(P=0.001). Conclusion : These results suggest that moxibustion is an effective treatment for functional recovery in stroke patients.

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A Study on the Efficient Management of Volunteer Fire Department (의용소방대의 효율적 운영에 대한 연구)

  • Lee, Wonjoo;Oh, Hyunchul;Lee, Kiyoung
    • Fire Science and Engineering
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    • v.30 no.4
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    • pp.148-157
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    • 2016
  • The purpose of this study is to investigate the influence of organizational culture to the activities satisfaction of volunteer firefighter. For that, we surveyed 182 volunteer firefighters worked in Sejong city. The survey was analyzed the reliability in questionnaire design by SPSS 20.0 win program. The interrelationship of each factors were confirmed by analysis of frequency, percentage and regression analysis. The regression analysis was performed in order to investigate effects of group, development, hierachy, and rationality culture based organizational culture on activities satisfaction of volunteer firefighter. A factor of group and development culture in organizational culture was found to be a positive influence on the activities satisfaction of the volunteer firefighter under significance probability of < 0.05. The bigger group and development culture the volunteer fire department, the higher the activities satisfaction of the volunteer firefighter. This paper is expected to serve as a basis for the efficient operation of the volunteer fire department in Korea.

Higher Accident Rates for Older Drivers at Specific Urban Intersections Study on the Improvement of the Road Geometry (고령운전자를 고려한 도시부 교차로 기하구조 개선방안에 관한 연구)

  • Chong, Sang Min;Choi, Jai sung;Lee, Jong hak;Lee, Hyun gu
    • International Journal of Highway Engineering
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    • v.19 no.2
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    • pp.153-165
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    • 2017
  • PURPOSES : With the increasing number of older drivers in an aging society, there is a growing need for research and planning on traffic safety for the older drivers using an improved road geometry design. This study also proposed a modified urban road interchange design, which aims to keep the older drivers away from accident-prone and high-traffic areas of the city. METHODS : In this study, we examined accident data records of older drivers to identify accident-prone zones and intersections; we studied the road geometry at these zones and analyzed if it was an underlying cause for higher number of accidents. Based on the research and subsequent analysis, we suggested plans for improvement of road geometry design at these intersections. RESULTS :By studying historic data and analyzing factors that affect the likelihood of accidents of vehicles driven by older drivers and after studying suitable traffic accident prediction models, we identified the major variables that need to be modified at accident-prone intersections, such as the width of a left turn lane at an intersection and the radius of the right turn lane at a street corner. The results have a significance probability of less than 0.001 and a 95% confidence level. To improve safety at the identified intersection, this study suggests the installation of a left-turn-lane-shaped Positive Offset and a right-turn-lane-shaped Slip Lane concept and an adjustment of intervals between intersections.

Comparative analysis of the wind characteristics of three landfall typhoons based on stationary and nonstationary wind models

  • Quan, Yong;Fu, Guo Qiang;Huang, Zi Feng;Gu, Ming
    • Wind and Structures
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    • v.31 no.3
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    • pp.269-285
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    • 2020
  • The statistical characteristics of typhoon wind speed records tend to have a considerable time-varying trend; thus, the stationary wind model may not be appropriate to estimate the wind characteristics of typhoon events. Several nonstationary wind speed models have been proposed by pioneers to characterize wind characteristics more accurately, but comparative studies on the applicability of the different wind models are still lacking. In this study, three landfall typhoons, Ampil, Jongdari, and Rumbia, recorded by ultrasonic anemometers atop the Shanghai World Financial Center (SWFC), are used for the comparative analysis of stationary and nonstationary wind characteristics. The time-varying mean is extracted with the discrete wavelet transform (DWT) method, and the time-varying standard deviation is calculated by the autoregressive moving average generalized autoregressive conditional heteroscedasticity (ARMA-GARCH) model. After extracting the time-varying trend, the longitudinal wind characteristics, e.g., the probability distribution, power spectral density (PSD), turbulence integral scale, turbulence intensity, gust factor, and peak factor, are comparatively analyzed based on the stationary wind speed model, time-varying mean wind speed model and time-varying standard deviation wind speed model. The comparative analysis of the different wind models emphasizes the significance of the nonstationary considerations in typhoon events. The time-varying standard deviation model can better identify the similarities among the different typhoons and appropriately describe the nonstationary wind characteristics of the typhoons.

A Study on the Impacting Factors Influencing on the Volunteer Firefighter's Satisfaction in Sejong City Upon their Activities as a Volunteer Firefighter (세종특별자치시 의용소방대원의 활동 만족도에 미치는 영향 요인 연구)

  • Kim, Seon Woong;Lee, Wonjoo;Lee, Chang-Seop
    • Fire Science and Engineering
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    • v.30 no.1
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    • pp.96-103
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    • 2016
  • The purpose of this paper is to study effects of participation motivations, relationships, and compensation on a satisfaction in activity of volunteer firefighter. For this purpose, we surveyed 106 volunteer firefighter worked in Sejong city. The survey data was analyzed the reliability in questionnaire design by SPSS 20.0 win program. Also, the interrelationship of each factors were confirmed by analysis of frequency, percentage and regression analysis. Furthermore, the regression analysis was performed in order to investigate effects of motivations, interpersonal relationships, and compensation on a satisfaction in activity of volunteer firefighter. A factor of motivations, interpersonal relationships, and compensation was found to be a positive influence on a satisfaction in activity of volunteer firefighter under significance probability of < 0.05. The overall satisfaction was influenced in order of motivations, compensation, interpersonal relationships. This paper is expected to serve as a basis for the efficient operation of the Korean Volunteer Fire Department.

A Study on Baby Boomer's Job Mobility using Sequential Analysis (순차분석을 활용한 베이비붐 세대의 직업이동 분석)

  • Lim, Jung-Yeon;Lee, Young-Min
    • The Journal of the Korea Contents Association
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    • v.15 no.3
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    • pp.146-159
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    • 2015
  • The purpose of this study was to investigate the influential factors on the job mobility types and patterns of baby boomers over the past 15 years. Sequential analysis was conducted to analyze the data that were derived from Wave 1~15(1998~2013) of Korean Labor and Income Panel Study(KLIPS). In particular, we analyzed the job mobility types and frequency, conversion analysis, probability, and significance rate. The results were as follows: firstly, proportional rates of male baby boomer workers such as technical, functional, and agriculture workers were higher than those of professionals and semi-professionals, whereas in case of female baby boomer workers, proportional rate of office workers were lower than those of service and sales workers. It was showed that functional and labor workers significantly higher than others. We found that after retiring, they left their job to search for farming job or choose to work in secondary labor markets. We suggested that the retirement support system and management system should be designed and conducted in a good manner.

Determinants of Shopping Experience for Mall Shoppers: Empirical Investigation in an Emerging City of Raipur (India)

  • Singh, Harvinder;Prashar, Sanjeev;Agarwal, Rashmi;Sharma, Tarun Kumar
    • Asia-Pacific Journal of Business
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    • v.5 no.1
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    • pp.13-21
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    • 2014
  • Shopping malls have become key players in the Indian retail space. Even in upcoming Indian towns, malls have been mushrooming. Raipur, the capital city of the Indian state of Chhattisgarh has witnessed the growth over the last few years. However, this unplanned growth of malls in cities is expected to lead to oversupply of mall space in the near future, making things difficult for mall developers. The study is an attempt to identify appropriate strategies for mall developers to iron out such kinks. This paper presents 'shopping experience' as a tool to compete, succeed and explore its composition in terms of its constituent factors. The paper uses Exploratory Factor Analysis (EFA) on a non-probability sample of 350 respondents. It condenses a set of twenty-two mall variables into five factors that directly influence the shopping experience. These factors included ambience, infrastructure, marketing focus, convenience and safety and security. In terms of significance, shoppers assigned different weightage to each of these factors. The study shed light on interesting insights regarding the expectations of mall shoppers in the city of Raipur. The results though interesting, may be extended to different social, economic and geographic contexts to check the universality. While strategizing, mall developers must assign proportionate effort on the factors based on the respective contribution to shopping experience. In light of intensifying competition in Raipur, the study is significant for future prospects of malls. In the absence of a scientific and objective basis, the developers run risk of making wrong investment and management decisions. This paper is a useful addition to the body of knowledge on management of shopping malls in India and is unique in terms of its focus on mall shoppers in the smaller Indian cities like Raipur.

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