• 제목/요약/키워드: Sample Allocation

검색결과 143건 처리시간 0.03초

3단계 층화확률화응답모형 (Three-Stage Strati ed Randomize Response Model)

  • 김종민;채성산
    • 응용통계연구
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    • 제23권3호
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    • pp.533-543
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    • 2010
  • 직접면접으로 민감한 질문을 할때 발생하는 무응답이나 거짓응답의 문제를 개선하고자 Warner (1965)가 최초로 제안한 확률화응답모형에 관한 연구는 이후 많은 연구자들에 의해 개선, 발전되어 오고 있다. 본 연구에서 표본은 층화임의복원추출법에 의해 추출되었으며, 표본배분은 최적배분법에 의해 배분되었다. 한편, Kim과 Elam (2005)의 2단계 층화확률화응답모형을 확장한 3단계 층화확률화응답모형을 사용하였다. Kim과 Elam (2005)의 2단계 층화확률화응답모형과 상대효율을 비교한 결과 본 논문에서 제시한 3단계 층화확률화모형의 효율성이 상대적으로 높다는 결과가 도출되었다. 그러나 2단계확률화응답모형을 3단계로 확장함으로써 상대적으로 효율성은 증대되지만 반대로 조사과정의 어려움이 예상된다.

PubMed 검색을 통한 요추 추간판 탈출증의 침치료 연구 동향 (The Research Trends on the Acupuncture Treatment of Lumbar Herniated Intervertebral Disc Using PubMed Database)

  • 신우석;박원형;차윤엽
    • 한방재활의학과학회지
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    • 제24권4호
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    • pp.49-60
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    • 2014
  • Objectives The purpose of this study is to research current trends of acupuncture treatment of lumbar herniated intervertebral disc using the PubMed database. Methods We set up the search strategy and investigated clinical trials on acupuncture treatment of lumbar herniated intervertebral disc through PubMed search. This study analyzed previous researched papers published from January 1st, 2000 to April 30th, 2014, and classified them by publication year, journal names, types of literature, treatment methods and evaluation scales. To assess the quality of the reviewed literature, randomized controlled trial (RCT) studies were assessed by Cochrane's risk of bias (ROB) tool and non-RCT studies were assessed by risk of bias for non-randomized studies (RoBANS). Results We found 35 studies on the acupuncture treatment of lumbar herniated intervertebral disc. Papers on this topic have been published, on average, three to four times annually in 9 journals since the mid-2000's. The journal with the largest number of publications was Chinese Acupuncture & Moxibustion, and most of articles were classified as RCT. Acupuncture treatment was performed individually or together with other treatments. The most frequently used pain evaluation index was visual analogue scale (VAS). The index of effective rate was used frequently but there was a lack of objectivity. In regards to the quality of the studies, outcome assessment in RCT showed that random sequence generation, allocation concealment, and the blinding of participants and personnel increase potential of risk of bias. For non-RCT assessment, outcome showed that confounding variable, measurement of intervention were at high risk of bias. Conclusions In order to obtain objective clinical evidence of acupuncture treatment of lumbar herniated intervertebral disc, further clinical studies should be designed to minimize the risk of bias, using STRICTA with larger sample sizes.

한의학 연구에 활용된 통계분석 방법에 대한 고찰 (A Review of Statistical Analysis Methods Applied on Traditional Korean Medicine Research)

  • 장선일;윤용갑;최경호
    • 대한한의학방제학회지
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    • 제17권1호
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    • pp.75-83
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    • 2009
  • Objective : The purpose of this study is to indicate of problems in statistical analysis method of "The Korean Journal of oriental Medical Prescription" and we will be proposed the useful application of the statistical analysis method. Methods : In this paper, we were analysed statistical analysis methodology from published journal articles "The Korean Journal of Oriental Medical Prescription" December, year 2000 to December, year 2008. We were investigated of problems in application of structured analysis methods those journal articles that including statistical analysis techniques and analysis methods. Results : 1. A random allocation of the experimental group and control groups are important factors in the planning process of statistical analysis. However, there are less explanation those journal articles. 2. There are no consideration in specimen size that there will be considerate by the level of significance and statistical test. 3. Many article authors were confused between parametric methods and non-parametric methods that they were applied parametric statistical analysis methods although inapplicable sample size. 4. There were applied the parametric methods consists of t-test instead non-parametric methods in the comparison of average intergroup relations. 5. There were less understanding posterior analysis and were confused with t-test. Conclusion : Our goal was to outline the key methods with a brief discussion of problems(statistical analysis methods), avenues for solutions. we recommend authors to use an appropriate statistical analysis methods for obtaining a more cautions results.

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Web-based Three-step Project Management Model and Its Software Development

  • Hwang Heung-Suk;Cho Gyu-Sung
    • 한국경영과학회:학술대회논문집
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    • 대한산업공학회/한국경영과학회 2006년도 춘계공동학술대회 논문집
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    • pp.373-378
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    • 2006
  • Recently the technical advances and complexities have generated much of the difficulties in managing the project resources, for both scheduling and costing to accomplish the project in the most efficient manner. The project manager is frequently required to render judgments concerning the schedule and resource adjustments. This research develops an analytical model for a schedule-cost and risk analysis based on visual PERT/CPM. We used a three-step approach: 1) in the first step, a deterministic PERT/CPM model for the critical path and estimating the project time schedule and related resource planning and we developed a heuristic model for crash and stretch out analysis based upon a time-cost trade-off associated with the crash and stretch out of the project. 2) In second step, we developed web-based risk evaluation model for project analysis. Major technologies used for this step are AHP (analytic hierarchy process, fuzzy-AHP, multi-attribute analysis, stochastic network simulation, and web based decision support system. Also we have developed computer programs and have shown the results of sample runs for an R&D project risk analysis. 3) We developed an optimization model for project resource allocation. We used AHP weighted values and optimization methods. Computer implementation for this model is provided based on GUI-Type objective-oriented programming for the users and provided displays of all the inputs and outputs in the form of GUI-Type. The results of this research will provide the project managers with efficient management tools.

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일부 농촌지역 주민들의 건강결정 관련요인 (Factors Affecting Health of the Rural Residents)

  • 손동국;이규식;박종구;고상백;진기남;남은우;이해종
    • 보건행정학회지
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    • 제19권4호
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    • pp.1-17
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    • 2009
  • The purpose of this study was to find factors affecting health of the rural residents. The data were collected from a sample of 2,587 people aged from 40 to 70 in the year 2005-2006, Wonju City and Pyeongchang County, Gangwon-do, Korea. The theoretical model adopted in this study was the Lalonde's health field(human biology, environment, lifestyle, and health care organization). SF-12 was used to measure subjective health status. In the category of human biology, men were healthier than women. Age and BMI showed negative relation to health status. Income, education and social support showed positive relation to health status in the environment category. In the category of life style, stress showed negative relation to health status. Medical expenses showed negative relation to health status in the category of health care organization. After converting SF-12 score to percentage score, the health determinants portions were 47% lifestyle, 26% environment, 18% human biology and 9% health care organization. These findings suggest that life style, environment and biology are main factors in determinants of health. Especially stress in the life style category is more focused for the community health promotion. We also may be able to improve income, education and social support in the environment category with self empowerment efforts, community supports and government helps. Finally greater attention must be payed to life style in the future health planning and budget allocation priority in the healthcare area.

코로나바이러스감염증-19 (COVID-19) 환자들의 사망관련 인자에 대한 연구: 체계적 문헌고찰 및 메타분석 (Predictors of Mortality in Patients with COVID-19: A Systematic Review and Meta-analysis)

  • 김우림;한지민;이경은
    • 한국임상약학회지
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    • 제30권3호
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    • pp.169-176
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    • 2020
  • Background: Most meta-analyses of risk factors for severe or critical outcomes in patients with COVID-19 only included studies conducted in China and this causes difficulties in generalization. Therefore, this study aimed to systematically evaluate the risk factors in patients with COVID-19 from various countries. Methods: PubMed, Embase, and Web of Science were searched for studies published on the mortality risk in patients with COVID-19 from January 1 to May 7, 2020. Pooled estimates were calculated as odds ratio (OR) with 95% confidence interval (CI) using the random-effects model. Results: We analyzed data from seven studies involving 26,542 patients in total in this systematic review and meta-analysis. Among the patients, 2,337 deaths were recorded (8.8%). Elderly patients and males showed significantly higher mortality rates than young patients and females; the OR values were 3.6 (95% CI 2.5-5.1) and 1.2 (95% CI 1.0-1.3), respectively. Among comorbidities, hypertension (OR 2.3, 95% CI 1.1-4.6), diabetes (OR 2.2, 95% CI 1.2-3.9), cardiovascular disease (OR 3.1, 95% CI 1.5-6.3), chronic obstructive pulmonary disease (OR 4.4, 95% CI 1.7-11.5), and chronic kidney disease (OR 4.2, 95% CI 2.0-8.6) were significantly associated with increased mortalities. Conclusion: This meta-analysis, involving a huge global sample, employed a systematic method for synthesizing quantitative results of studies on the risk factors for mortality in patients with COVID-19. It is helpful for clinicians to identify patients with poor prognosis and improve the allocation of health resources to patients who need them most.

Bayesian Method for Modeling Male Breast Cancer Survival Data

  • Khan, Hafiz Mohammad Rafiqullah;Saxena, Anshul;Rana, Sagar;Ahmed, Nasar Uddin
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권2호
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    • pp.663-669
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    • 2014
  • Background: With recent progress in health science administration, a huge amount of data has been collected from thousands of subjects. Statistical and computational techniques are very necessary to understand such data and to make valid scientific conclusions. The purpose of this paper was to develop a statistical probability model and to predict future survival times for male breast cancer patients who were diagnosed in the USA during 1973-2009. Materials and Methods: A random sample of 500 male patients was selected from the Surveillance Epidemiology and End Results (SEER) database. The survival times for the male patients were used to derive the statistical probability model. To measure the goodness of fit tests, the model building criterions: Akaike Information Criteria (AIC), Bayesian Information Criteria (BIC), and Deviance Information Criteria (DIC) were employed. A novel Bayesian method was used to derive the posterior density function for the parameters and the predictive inference for future survival times from the exponentiated Weibull model, assuming that the observed breast cancer survival data follow such type of model. The Markov chain Monte Carlo method was used to determine the inference for the parameters. Results: The summary results of certain demographic and socio-economic variables are reported. It was found that the exponentiated Weibull model fits the male survival data. Statistical inferences of the posterior parameters are presented. Mean predictive survival times, 95% predictive intervals, predictive skewness and kurtosis were obtained. Conclusions: The findings will hopefully be useful in treatment planning, healthcare resource allocation, and may motivate future research on breast cancer related survival issues.

빠른 하드웨어/소프트웨어 통합합성을 위한 데이타플로우 명세로부터의 하드웨어 합성 (Hardware Synthesis From Coarse-Grained Dataflow Specification For Fast HW/SW Cosynthesis)

  • 정현욱;하순회
    • 한국정보과학회논문지:시스템및이론
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    • 제32권5호
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    • pp.232-242
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    • 2005
  • 이 논문에서는 빠른 하드웨어/소프트웨어 통합합성을 위해 데이타플로우 그래프(DFG: Dataflow Graph)로부터 하드웨어를 자동으로 합성하는 내용을 다룬다. 이 데이타플로우 그래프에서 로드는 FIR(Finite Impulse Response) 필터나 DCT(Discrete Cosine Transform) 블록과 같이 크기가 어느 정도 되는 하드웨어 블록을 나타내며, 이 노드의 포트는 한번 수행할 때마다 하나 이상의 데이타 샘플을 주고 받을 수 있다. 즉, 멀티레이트 데이타 샘플(multi-rate data sample)을 교환한다. 이러한 특성들은 기존의 Behavioral Synthesis와 구별되는 점이며, 따라서 Behavioral Synthesis보다 어려운 문제가 된다. 본 논문에서 제안하는 설계 방법을 사용하면 알고리즘을 명세하는 데이타플로우 그래프는 하드웨어 리소스의 할당과 스케줄 정보에 따라 다양한 하드웨어 구조로 매핑될 수 있다. 따라서 하드웨어 설계시에 면적/성능 트레이드오프 관계를 손쉽게 관리할 수 있으며, 하드웨어를 자동으로 합성하는 기존의 방식보다구현 가능한 하드웨어 설계 공간을 더욱 넓혀주는 효과를 거둘 수 있다.

Evaluation of the alignment efficiency of nickel-titanium and copper-nickel-titanium archwires in patients undergoing orthodontic treatment over a 12-week period: A single-center, randomized controlled clinical trial

  • Aydin, Burcu;Senisik, Neslihan Ebru;Koskan, Ozgur
    • 대한치과교정학회지
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    • 제48권3호
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    • pp.153-162
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    • 2018
  • Objective: The aim of this trial was to compare the alignment efficiency and intermaxillary arch dimension changes of nickel-titanium (NiTi) or copper-nickel-titanium (CuNiTi) round archwires with increasing diameters applied sequentially to the mandibular arch. Methods: The initial alignment phase of fixed orthodontic treatment with NiTi or CuNiTi round archwires was studied in a randomly allocated sample of 66 patients. The NiTi group comprised 26 women, 10 men, and the CuNiTi ($27^{\circ}C$) group comprised 20 women, 10 men. The eligibility criteria were as follows: anterior mandibular crowding of minimum 6 mm according to Little's Irregularity Index (LII), treatment requiring no extraction of premolars, 12 to 18 years of age, permanent dentition, skeletal and dental Class I malocclusion. The main outcome measure was the alignment of the mandibular anterior dentition; the secondary outcome measure was the change in mandibular dental arch dimensions during 12 weeks. Simple randomization (allocation ratio 1:1) was used in this single-blind study. LII and mandibular arch dimensions were measured on three-dimensional digital dental models at 2-week intervals. Results: No statistically significant difference was observed between NiTi and CuNiTi according to LII (p > 0.05). Intercanine and intermolar arch perimeters increased in the CuNiTi group (p < 0.001). Inter-first premolar width showed a statistically significant interaction in week ${\times}$ diameter ${\times}$ application (p < 0.05). Conclusions: The effects of NiTi and CuNiTi round archwires were similar in terms of their alignment efficiency. However, the intercanine and intermolar arch perimeters, and the inter-first premolar width changes differed between groups.

독신가구의 경제생활에 대한 탐색적 연구 (An Exploratory Study on the Economic Life of Single Households)

  • 심영
    • 가정과삶의질연구
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    • 제20권6호
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    • pp.197-208
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    • 2002
  • The purpose of this study was to investigate the economic lives of single households with the age of 30 through less than 50. The economic life was examined in three aspects; income, assets, and consumption expenditures and patterns. One hundred sixty single households were surveyed, with questionnaires for 15days from April 1 to April 15 of 2002, and analyzed with descriptive statistics. The results were as follows: about 30.8% of total single households in the sample were in the income group of 1,500,000 thought less than 2,000,000 won. The size of income for the 30's was less than that for the 40's. Compared with male single households, female single households were more in both low and high levels of income. The saving rate tended more or less to be low. The more the age, the higher the saving rate. As for debt, the 40's single households, male single households, high school single households (compared to the 30's single households, female single households, university and graduate single households, respectively) were relatively higher. In general, the single households tended to have debts due to preparation for housing, credit over use. The assets tended to be managed by themselves. The economic preparation for the old life was done by banking system rather than insurance. The average monthly living costs was higher in the age of the 40's single than the age of the 30's single. The living costs of the female single households was higher or lower than those of the male single households. As for consumption patterns, there was the most in the expenditure allocation for food away from home, then for culture entertainmentㆍsocial life, and for clothing and shoes. As for the convenience of the consumption life in overall, there were more responses in moderation and inconvenience than in convenience.