• Title/Summary/Keyword: Probability and statistics

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The Effect of Mindfulness Meditation Programs on Nursing College Students' Perceived Stress, Depression, and Self-efficacy (마음챙김 명상프로그램이 간호대학생의 스트레스 지각, 우울 및 자아효능감에 미치는 효과)

  • Yeom, Young-Ran;Choi, Keum-Bong
    • Journal of East-West Nursing Research
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    • v.19 no.2
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    • pp.104-113
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    • 2013
  • Purpose: Due to the academic demands from a theory and practice-based educational program, nursing students often experience psychological burdens. The purpose of this study was to investigate the effect of mindfulness meditation programs on nursing students' perceived stress, depression, and self-efficacy. Methods: A quasi-experimental study with a non-equivalent control group pretest-posttest design was used. Participants were recruited from two nursing colleges. The sample consisted of an intervention group (n=29) that participated in a mindfulness meditation program and a control group (n=30). The experimental group participated in the program for 120 minutes a week for a total of 8 sessions. The data were collected prior and after the intervention using self-administered questionnaires. Data were analyzed using descriptive statistics, $X^2$-test, Fisher's exact probability test, and the t-test. Results: After the application of the mindfulness meditation program, the experimental group showed a significant difference in perceived stress(t=-10.33, p<.001), depression (t=-2.17, p=.035), and self-efficacy (t=2.57, p=.013) scores. However, there was no significant differrence in the control group. Conclusion: These findings provide a supportive evidence of mindfulness meditation program as a behavioral intervention to reduce stress, depression and increase self-efficacy among nursing students.

The effect of missing levels of nesting in multilevel analysis

  • Park, Seho;Chung, Yujin
    • Genomics & Informatics
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    • v.20 no.3
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    • pp.34.1-34.11
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    • 2022
  • Multilevel analysis is an appropriate and powerful tool for analyzing hierarchical structure data widely applied from public health to genomic data. In practice, however, we may lose the information on multiple nesting levels in the multilevel analysis since data may fail to capture all levels of hierarchy, or the top or intermediate levels of hierarchy are ignored in the analysis. In this study, we consider a multilevel linear mixed effect model (LMM) with single imputation that can involve all data hierarchy levels in the presence of missing top or intermediate-level clusters. We evaluate and compare the performance of a multilevel LMM with single imputation with other models ignoring the data hierarchy or missing intermediate-level clusters. To this end, we applied a multilevel LMM with single imputation and other models to hierarchically structured cohort data with some intermediate levels missing and to simulated data with various cluster sizes and missing rates of intermediate-level clusters. A thorough simulation study demonstrated that an LMM with single imputation estimates fixed coefficients and variance components of a multilevel model more accurately than other models ignoring data hierarchy or missing clusters in terms of mean squared error and coverage probability. In particular, when models ignoring data hierarchy or missing clusters were applied, the variance components of random effects were overestimated. We observed similar results from the analysis of hierarchically structured cohort data.

Effects of an Educational Program for the Reduction of Physical Restraint Use by Caregivers in Geriatric Hospitals (노인전문병원 간호제공자의 신체적 억제대 사용 감소를 위한 교육 프로그램의 효과)

  • Choi, Keum-Bong;Kim, Jin-Sun
    • Journal of Korean Academy of Nursing
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    • v.39 no.6
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    • pp.769-780
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    • 2009
  • Purpose: The purposes of this study were to develop an educational program to reduce the use of physical restraints for caregivers in geriatric hospitals and to evaluate the effects of the program on cargivers' knowledge, attitude and nursing practice related to the use of physical restraints. Methods: A quasi experimental study with a non-equivalent control group pretest-posttest design was used. Participants were recruited from two geriatric hospitals. Eighteen caregivers were assigned to the experimental group and 20 to the control group. The data were collected prior to the intervention and at 6 weeks after the intervention through the use of self-administered questionnaires. Descriptive statistics, $\chi^2$ test, Fisher's exact probability test, and Mann-Whitney U test were used to analyze the data. Results: After the intervention, knowledge about physical restraints increased significantly in experimental group compared to the control group. However, there were no statistically significant differences between the groups for attitude and nursing practice involving physical restraints. Conclusion: Findings indicate that it is necessary to apply knowledge acquired through educational programs to nursing practice to reduce the use of physical restraints. User friendly guidelines for physical restraints, administrative support of institutions, and multidisciplinary approaches are required to achieve this goal.

The impact of hair coat color on longevity of Holstein cows in the tropics

  • Lee, C.N.;Baek, K.S.;Parkhurst, A.
    • Journal of Animal Science and Technology
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    • v.58 no.12
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    • pp.41.1-41.7
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    • 2016
  • Background: Over two decades of observations in the field in South East Asia and Hawai'i suggest that majority of the commercial dairy herds are of black hair coat. Hence a simple study to determine the accuracy of the observation was conducted with two large dairy herds in Hawaii in the mid-1990s. Methods: A retrospective study on longevity of Holstein cattle in the tropics was conducted using DairyComp-305 lactation information coupled with phenotypic evaluation of hair coat color in two large dairy farms. Cows were classified into 3 groups: a) black (B, >90%); b) black/white (BW, 50:50) and c) white (W, >90%). Cows with other hair coat distribution were excluded from the study. In farm A, 211 out of 970 cows were identified having 4 or more lactations. In farm B, 690 out of 1,350 cows were identified with 2 or more lactations for the study. Results: The regression analyses and the Wilcoxon-Log-rank test for survival probability showed that Holstein cattle with 90% black hair coat had greater longevity compared to Holstein cattle with 90% white hair coat. Conclusions: This study suggests that longevity of Holstein cattle in tropical regions was influenced by hair coat color and characteristics.

Stochastic independence of events in the middle and high school education course -Focusing on the connections between math concepts- (중등교과과정에서의 사건의 독립에 관한 연구 -수학 개념들 간의 연결을 중심으로-)

  • Kim, Sung-Lai;Seo, J.J.
    • Journal of the Korean School Mathematics Society
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    • v.15 no.1
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    • pp.199-214
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    • 2012
  • Stochastic independence of events is not only important concept but useful role in statistics and probability. In this paper, we investigate and analyze the definition of stochastic independence used in the middle and high school mathematics education course. and We investigated that students know concept of independent events. As a result, students was a lack of understanding about the concepts associated with independence of events. and the connection between concepts associated with independent of events were partially. Also, Connections between lower-level concepts and high-level concepts can be done well so teaching-learning was needed.

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Knowledge Base Associated with Autism Construction Using CRFs Learning

  • Yang, Ronggen;Gong, Lejun
    • Journal of Information Processing Systems
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    • v.15 no.6
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    • pp.1326-1334
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    • 2019
  • Knowledge base means a library stored in computer system providing useful information or appropriate solutions to specific area. Knowledge base associated with autism is the complex multidimensional information set related to the disease autism for its pathogenic factor and therapy. This paper focuses on the knowledge of biological molecular information extracted from massive biomedical texts with the aid of widespread used machine learning methods. Six classes of biological molecular information (such as protein, DNA, RNA, cell line, cell component, and cell type) are concerned and the probability statistics method, conditional random fields (CRFs), is utilized to discover these knowledges in this work. The knowledge base can help biologists to etiological analysis and pharmacists to drug development, which can at least answer four questions in question-answering (QA) system, i.e., which proteins are most related to the disease autism, which DNAs play important role to the development of autism, which cell types have the correlation to autism and which cell components participate the process to autism. The work can be visited by the address http://134.175.110.97/bioinfo/index.jsp.

Bandwidth selection for discontinuity point estimation in density (확률밀도함수의 불연속점 추정을 위한 띠폭 선택)

  • Huh, Jib
    • Journal of the Korean Data and Information Science Society
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    • v.23 no.1
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    • pp.79-87
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    • 2012
  • In the case that the probability density function has a discontinuity point, Huh (2002) estimated the location and jump size of the discontinuity point based on the difference between the right and left kernel density estimators using the one-sided kernel function. In this paper, we consider the cross-validation, made by the right and left maximum likelihood cross-validations, for the bandwidth selection in order to estimate the location and jump size of the discontinuity point. This method is motivated by the one-sided cross-validation of Hart and Yi (1998). The finite sample performance is illustrated by simulated example.

Risk Evaluation Based on the Time Dependent Expected Loss Model in FMEA (FMEA에서 시간을 고려한 기대손실모형에 기초한 위험 평가)

  • Kwon, Hyuck-Moo;Hong, Sung-Hoon;Lee, Min-Koo;Sutrisno, Agung
    • Journal of the Korean Society of Safety
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    • v.26 no.6
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    • pp.104-110
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    • 2011
  • In FMEA, the risk priority number(RPN) is used for risk evaluation on each failure mode. It is obtained by multiplying three components, i.e., severity, occurrence, and detectability of the corresponding failure mode. Each of the three components are usually determined on the basis of the past experience and technical knowledge. But this approach is not strictly objective in evaluating risk of a given failure mode and thus provide somewhat less scientific measure of risk. Assuming a homogeneous Poisson process for occurrence of the failures and causes, we propose a more scientific approach to evaluation of risk in FMEA. To quantify severity of each failure mode, the mission period is taken into consideration for the system. If the system faces no failure during its mission period, there are no losses. If any failure occurs during its mission period, the losses corresponding to the failure mode incurs. A longer remaining mission period is assumed to incur a larger loss. Detectability of each failure mode is then incorporated into the model assuming an exponential probability law for detection time of each failure cause. Based on the proposed model, an illustrative example and numerical analyses are provided.

Relationship between Phase Properties, Significant Duration and PGA from the Earthquake Records of Mw 5.5~6.5 (Mw 5.5~6.5 지진동의 위상특성과 계속시간 및 PGA와의 관계)

  • Choi, Hang;Yoon, Byung Ick
    • Journal of the Earthquake Engineering Society of Korea
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    • v.23 no.1
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    • pp.55-70
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    • 2019
  • The phase properties of ground acceleration records from Mw 5.5~6.5 earthquakes are analyzed. The interrelationships between phase properties and significant durations, as well as PGA, are clarified through both of theoretical and empirical approaches. The probabilistic characteristics of phase information is also discussed based on previous studies and it is shown that circular normal distribution is the most appropriate probability distribution for the phase angle and phase difference. Whereas those variates can be modeled by Gaussian random variables. From the survey results on the frequency dependency of the phase statistics, a simple model is introduced, which is possible to express the frequency dependency of phase information. It is also shown that the significant duration can be controlled by appropriately chosen standard deviation of phase difference for 4~8Hz frequency band and additional consideration of phase scattering in higher frequency band through a series of Monte Carlo simulations. The source of phase scattering effect is also pointed out and discussed.

The Study of Historical Analysis and Educational Extension on Derangement (교란순열에 대한 역사적 탐색과 교육적 확장에 대한 연구)

  • Suh, Bo Euk
    • Journal for History of Mathematics
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    • v.32 no.2
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    • pp.61-77
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    • 2019
  • The study was conducted based on the 'method of mathematical exploration through history'. In recent school education, 'Probability and Statistics' education has been emphasized, and as a result, the study has conducted a study on permutations. Permutation is used in a variety of fields, and in this study, we looked at the Derangement. The results of this study are as follows. First, analysis was made at current school mathematics level and academic mathematics level for Derangement. Second, the historical development process of derangement was examined. Third, based on this, the research direction of this study was decided to be 'Derangement number's triangle(Rencontres number's triangle)', and the inquiry for education expansion was carried out. Fourth, we have presented data on concrete educational expansion by discovering various mathematical facts of the Derangement number's triangle. We hope that the results of this study will provide meaningful implications for the application of mathematics and the presentation of new inquiry directions.