• Title/Summary/Keyword: 짝의 t-검정

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Tests for Incomplete Paired Data (불완전한 짝자료에 대한 검정법)

  • 이승묵;박진경;박태성
    • The Korean Journal of Applied Statistics
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    • v.12 no.2
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    • pp.415-432
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    • 1999
  • 짝자료(paired data)에서 결측값이 발생했을 때에 이 자료를 처리할 수 있는 여러통계검정 방법들을 고찰해보았다. 결측값들을 어떻게 처리하는 지에 따라서 다섯 가지 방법으로 분류해 보았고, 이 방법들이 짝 t-검정에 미치는 효과를 모의실험을 통해 비교해 보았다. 결측값들에 대한 세 종류의 메카니즘을 고려하여 검정크기와 검정력을 구하였다.

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Statistical Issues in the Articles Published in the Journal of Veterinary Clinics (한국임상수의학회지에 발표된 논문의 통계분석 검토)

  • Pak, Son-Il;Oh, Tae-Ho
    • Journal of Veterinary Clinics
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    • v.27 no.2
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    • pp.170-174
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    • 2010
  • With the ease availability of statistical software and powerful computers the application of statistical methods in domestic veterinary journals is on the increase. In parallel with this benefit, statistical errors are not uncommon even in renowned scientific and medical journals. These errors may lead to misinterpretation of the data, thereby, subjected to faulty conclusions. A systematic review of articles published in 8 issues of the Journal of Veterinary Clinics during 2006-2007 was performed to assess the statistical methodology and reporting. Ninety-four (72.9%) articles of the 129 original articles screened included any inferential statistical analysis in the article, including comparison of 3 or more groups (53 or 56.4%), comparison of independent 2 groups (40 or 42.6%), and paired t-test (9 or 9.6%) in order. Of the 94 articles in which statistical analysis was done 62 (or 66.0%) had at least 1 statistical error. Errors included failure to apply or incorrectly applying independent Student's t-test for paired data or vice versa, inappropriate use of t-test for more than 3 groups and failure in chi-square test to consider continuity-correction for small expected frequencies. The common errors in ANOVA were failure to validate assumption of the test, inappropriate post-hoc multiple-comparison and incorrect assumption of independence of data in repeated measures design. Reporting errors included failure to state statistical methods and failure to state specific test if more than 1 test was done. It is suggested that an editorial effort would be necessary to achieve the improvement of appropriate statistical procedures through the publication of statistical guidelines to author(s).

A Case Study of Applying Flipped Learning and Team-based Learning in University Subject, Business Communication (경영학 수업에서 학습자 중심 교수법 적용 사례 -비즈니스 커뮤니케이션을 중심으로)

  • Choi, Seung-Nyun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.4
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    • pp.126-137
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    • 2020
  • This study provided implications for applying learner-centered teaching methods in the field of management education by adopting flipped learning and team-based learning to Business Communication classes and operating the classes according to its characteristics. Business communication capability, especially related to drawing up a document or a written report, is considered one of the crucial factors for making individuals valuable in an organization. For the identification of the subject outputs, a total of 64 students from the first and second semesters in 2018 were sampled, and the Wilcoxon signed rank test and paired t-tests were carried out. The results show that all types of communication capabilities have significantly increased at the end of each of the semesters. Also, the overall satisfaction level proved to be higher at the end rather than at the beginning of each semester. This study is especially meaningful because the results suggest concrete ways to apply learner-centered teaching methods for business education.

Effect of Speed of Movement on Maximum Ground Reaction Force During the Sit-to-Stand Transfer (앉은 자세에서 일어서는 동안에 움직임의 속도가 최대 지면반발력에 미치는 영향)

  • Lee, Sanghyub
    • Physical Therapy Korea
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    • v.5 no.4
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    • pp.20-29
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    • 1998
  • 연구의 배경 앉은 자세에서 일어서기는 일상생활동작중 흔한 동작중의 하나이다. 노인들을 포함한 많은 환자들은 앉은 자세에서 일어서기에 어려움이 있고 속도가 감소한다. 이 연구의 목적은 다른 두 속도로 앉은 자세에서 일어서는 동작을 실행할 때 최대 지면반발력의 세개의 요소를 비교하는 것이다. 대상자 22명의 건강한 성인 (20-36세)을 대상으로 하였다. 실험방법 앉은 자세에서 일어서기동작 수행중 최대 지면반발력을 측정하기 위하여 힘판을 사용하였다. 대상자들은 메트로놈을 이용하여 각각 느린 속도 (3초: 총 앉은 자세에서 일어서기동작 수행시간)와 빠른 속도(1.5초)에서 앉은 자세에서 일어서기를 수행하였다. 느린 속도와 빠른 속도중 최대 지면반발력을 비교하기 위해 짝비교 t-검정을 사용하였다. 결과 빠른 속도시 최대 지면반발력의 수직(p<0.05), 전-후(p<0.05), 내-외(p<0.05) 요소에서 느린 속도시와 차이가 있었다. 최대 지면반발력의 모든 요소가 움직임의 속도의 증가에 비례하여 증가하였다. 토의 및 결론 빠른 속도의 앉은 자세에서 일어서기를 수행하기 위해서는 최대 지면반발력의 수직, 전-후요소의 추진력이 요구된다. 최대 지면반발력의 내-외요소는 상전방으로 작용하는 모멘트의 증가에 대한 제동력으로 생각된다. 또한, 빠른 속도로 앉은 자세에서 일어서기 동작을 수행하기 위하여 추진력은 일어서는 순간의 모멘트에 대한 지면반발력의 내-외요소에 영향을 미친다. 이라한 결과들은 앉은 자세에서 일어서기 동작에 어려움을 갖는 노인이나 환자들의 노력을 덜기위해 느린 속도의 움직임이 필요함을 제안한다.

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A Convergence Study on the Effects of Core Nursing Skills Improvement Program on Nursing Skills Competence in Nursing Students (핵심간호술 강화프로그램이 간호학생의 간호술 수행능력에 미치는 효과에 관한 융합연구)

  • Ha, Young-ok;An, Ji-Yoen
    • Journal of the Korea Convergence Society
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    • v.8 no.5
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    • pp.223-231
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    • 2017
  • This convergence study was done to identify the effectiveness of core nursing skills improvement program on nursing skills competence in nursing students. The design of research was one group pretest-posttest and the participants were 158 nursing students. The core nursing skills improvement program was composed of 7 fundamental nursing skills(vital sign, intramuscular injection, oral medication, subcutaneous injection, enema, oxygen therapy and nelaton). The data were collected using self-report questionnaires from January 19 to 23, 2015 and analyzed using paired t-test. The mean score of nursing skills competence in posttest was significantly higher than those in pretest (t=-4.71 ~ -8.00, p<.001). The score for self-confidence(t=-11.61, p<.001) and that for problem solving skills(t=-2.04, p=.043) increased significantly after core nursing skills improvement program. The results indicate that core nursing skills improvement program was effective in improving nursing skills competence.

Effects of Thorax Mobility Exercise on the Thorax Mobility, Breathing Pattern and Respiratory Capacity in Subject With Restricted Thorax Mobility: A Case Series (가슴 가동성 제한을 가지고 있는 대상자에게 가슴 가동성 운동이 가슴가동성, 호흡패턴 및 호흡량에 미치는 효과: 사례 시리즈)

  • Ha, Sungmin
    • Therapeutic Science for Rehabilitation
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    • v.12 no.2
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    • pp.99-107
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    • 2023
  • Objective : To investigate the effects of thorax mobility exercises on thorax mobility, breathing pattern, and respiratory capacity in subjects with restricted thorax mobility. Methods : Thirteen subjects with restricted thorax mobility participated in this study. Measurement of thorax circumference using a tape measure (difference between inhalation and exhalation), breathing pattern (distance of rib cage elevation during breathing), and respiratory capacity was performed. Paired t-test was used to compare the thorax mobility, breathing pattern, and respiratory capacity between before and after thorax mobility excercise. Statiscal significance was set at .05. Results : There were significant differences in thorax mobility and breathing pattern, but no significant difference in respiratory capacity (p < .05). Conclusion : Based on the results of this study, thorax mobility exercise using the rib mobilization technique is considered to be a method that can improve thorax mobility and normalize abnormal breathing patterns that cause rib cage elevation.

The Development of RFID Utility Statistical Analysis Tool (RUSAT) in Comparison to Barcode for Logistics Activities (물류활동에서 RFID와 바코드 시스템의 효용성 비교를 위한 통계분석 도구(RUSAT) 개발)

  • Ha, Heon-Cheol;Park, Heung-Sun;Kim, Hyun-Soo;Choi, Yong-Jung
    • Journal of the Korea Society of Computer and Information
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    • v.17 no.5
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    • pp.137-146
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    • 2012
  • In SCM(Supply Chain Management), a management paradigm where the customer satisfaction is to be achieved by minimizing the cost, reducing the uncertainty, and obtaining the overall optimization. As it performs the integrated operation of the paths of information, assets, and knowledge from the raw material providers to the retailers, the adoption of RFID(Radio Frequency Identification) in SCM could be expected to magnify the effectiveness of the system. However, there is a huge risk by deciding whether or not RFID system is adopted without the objective analysis under the uncertain circumstances. This research paper presents the statistical analysis methodologies for the comparison of RFID with Barcode on the aspect of utility and the statistical analysis tool, RUSAT, which was programmed for nonstatisticians' convenience. Assuming a pharmaceutical industry, this paper illustrates how the data were entered and analyzed in RUSAT. The results of this research are expected to be used not only for the pharmaceutical related company but also for the manufacturer, the whole-saler, and the retailer in the other logistic industries.

The Effect of Application of a Non-Elastic Fixation Belt on the Balance Ability and Fall Prevention in Elderly Women (비탄력 고정식 벨트가 노인 여성의 균형능력과 낙상예방에 미치는 영향)

  • Lee, Jang-Tae;Chon, Seung-Chul
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.2
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    • pp.398-404
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    • 2017
  • The aim of this study was to determine the effect of a non-elastic fixation belt on the balance ability and fall prevention in elderly women. Elderly women experience reduced balance ability and an increased risk of falls due to a weakening of the surrounding sacroiliac joint and pelvic muscles during childbirth and menopause. On the other hand, specific studies are still needed. The subjects were allocated randomly to two groups: control (n=20) and experimental (n=20). The experimental group used a non-elastic fixation belt, whereas the control group had no fixation belt. The balance ability and the fall index were measured in all subjects using a balance measurement device, and the low abdominal muscle thickness was determined in the experimental group using ultrasound imaging for the exact application of the non-elastic fixation belt. The following statistical analysis was performed: an independent t-test for the general characteristics of the subjects, $2{\times}2$ analysis of variance with repeated measures for the balance and fall index score, and a paired t-test for the abdominal muscle thickness. The group ${\times}$ time interaction effect showed significant improvement in the General Stability Index (F1,38=47.24, p=0.001), Fourier Harmony Index (F1,38=88.83, p=0.001), Weight Distribution Index (F1,38=50.21, p=0.001), and Fall Index (F1,38=21.59, p=0.001). The thicknesses of the transverse abdominal (p=0.001) and internal oblique (p=0.001) muscles were increased significantly in the experimental group after using the non-elastic fixation belt. Overall, the application of a non-elastic fixation belt could be effective in improving the balance ability and fall prevention in elderly women.

Evaluations of the Accuracy and Reliability of Measurements Made on White Light Scanner-based Dental Digital Models (백색광 스캐너로 채득된 치과용 디지털모형의 정확도와 신뢰도 평가)

  • Kim, Ki-Baek;Kim, Jae-Hong
    • The Journal of the Korea Contents Association
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    • v.12 no.10
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    • pp.357-364
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    • 2012
  • Dental scanner-based dental digital models have been developed that have the potential to replace conventional stone model. The aim of this study was examine the accuracy and reliability of measurements made on digital models. A master model with the prepared upper full arch tooth was used. Stone model(N=10) were produced from master model, and on the other hands, digital models were made with the white light scanner(Identica, korea). One examiner individually measured 6 parameters on the conventional model and the digital models on two occasions. The student's t-test for paired samples and intra-class correlation coefficient(ICC) were used for statistical analysis. At the intra-examiner reliability of measurement, ICC at the stone and digital models were 0.75 and 0.87. The mean difference between measurements made directly on the stone models and those made on the digital models was 0.11-0.23mm, and was statistically significant(P<0.05). These in vitro studies show that accuracy of the digital model is similar to that of the stone model. These results will have to be confirmed in further clinical studies.

Changes of Recognition to Death Before and After Observation on the Cadaver Dissection to Paramedical Students (해부용시신을 이용한 참관 해부실습 후 죽음에 대한 인식의 변화)

  • Cho, Keun-Ja;Kim, Sooil
    • Anatomy & Biological Anthropology
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    • v.31 no.4
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    • pp.159-165
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    • 2018
  • The aim of this study is to identify changes of recognition to death before and after observation on the cadaver dissection to paramedical students. This study was done on 472 freshmen using questionnaire survey. Recognition to death questionnaire was consisted of 36 items. Data were collected before and after observation on the cadaver dissection with agreement of subjects. The data were analyzed using SPSS win 24.0. This study showed that recognition to death was significantly increased after observation on the cadaver dissection (3.19 points) than before observation on the cadaver dissection (3.06 points) (p=.000). Especially, anxiety on death was significantly increased (p=.000), and interest in death was significantly increased, too (p=.000). The results of this study suggest that we need positively to encourage observation on the cadaver dissection for paramedical students with providing program to decrease anxiety on death because of not only improving anatomy knowledge but also increasing recognition to death.