• Title/Summary/Keyword: Probability and statistics

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Indian Parents Prefer Vaccinating their Daughters against HPV at Older Ages

  • Madhivanan, Purnima;Srinivas, Vijaya;Marlow, Laura;Mukherjee, Soumyadeep;Narayanappa, Doddaiah;Mysore, Shekar;Arun, Anjali;Krupp, Karl
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.1
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    • pp.107-110
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    • 2014
  • Background: Increasing uptake of human papillomavirus (HPV) vaccine should be a priority in developing countries since they suffer 88% of the world's cervical cancer burden. In many countries studies show that age at vaccination is an important determinate of parental acceptability. This study explores parental preferences on age-to-vaccinate for adolescent school-going girls. Materials and Methods: The sample was selected using a two-stage probability proportional to size cluster sampling methodology. Questionnaires were sent home with a random sample of 800 adolescent girls attending 12 schools in Mysore to be completed by parents. Descriptive statistics including frequencies, percentages and proportions were generated for independent variables and bivariate analyses (Chi square test) were used to assess the relationship between independent and appropriate age-to-vaccinate. Results: HPV vaccination acceptability was high at 71%. While 5.3% of parents felt girls should be vaccinated by 10 years or younger; 38.3% said 11-15 years; 14.8% said 16-18 years; 5.8% suggested over 19 years; and 33% didn't know. Only 2.8% of parents would not vaccinate their daughters. Conclusions: Delaying HPV vaccination until later ages may signifivantly increase uptake of the HPV vaccine in India.

Standardization for basic association measures in association rule mining (연관 규칙 마이닝에서의 평가기준 표준화 방안)

  • Park, Hee-Chang
    • Journal of the Korean Data and Information Science Society
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    • v.21 no.5
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    • pp.891-899
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    • 2010
  • Association rule is the technique to represent the relationship between two or more items by numerical representing for the relevance of each item in vast amounts of databases, and is most being used in data mining. The basic thresholds for association rule are support, confidence, and lift. these are used to generate the association rules. We need standardization of lift because the range of lift value is different from that of support and confidence. And also we need standardization of support and confidence to compare objectively association level of antecedent variables for one descendant variable. In this paper we propose a method for standardization of association thresholds considering marginal probability for each item to grasp objectively and exactly association level, check the conditions for association criteria and then compare association thresholds with standardized association thresholds using some concrete examples.

Estimating Effects of Attributes on Choice of Pizza Restaurants by Purchase Frequency (구매빈도별 피자전문점 선택에 미치는 속성의 영향 평가)

  • Kang, Jong-Heon;Jeong, In-Suk
    • Korean Journal of Human Ecology
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    • v.15 no.3
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    • pp.491-499
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    • 2006
  • The purpose of this study is to measure the pizza purchasing behavioral characteristics of respondents and importances of factors affecting pizza purchase, to estimate the effects of attributes on choice of pizza restaurant, and to predict probability of selecting a particular pizza restaurant. The questionnaire consisted of two parts: The paired experimental profiles, purchasing behavior and importances of factors affecting pizza purchase. This study generated profiles of 16 hypothetical pizza restaurants based on seven attributes. The profiles comprised 16 discrete sets of variables, each of which had two levels. For this study, researcher randomly selected 150 university students as respondents. Twenty one students did not complete the survey instrument, resulting in a final sample size of 129. All estimations were carried out using frequencies, $X^2$, independent samples t-test, phreg procedure of SAS package. The results were as followed: Some purchasing behavioral characteristics and importances of factors affecting pizza purchase were significantly different by purchase frequency. Based on the estimated models developed for the two purchase frequency groups, the Chi-square statistics were significant at p<0.001. The parameter estimate for late delivery time with frequently purchase frequency group was highest, and the parameter estimate for price with frequently purchase frequency group was highest. The pizza restaurants that charged 20,000 won, offered 100% discount on eleventh pizza, promised to deliver pizza in 20 min, usually delivered the pizza as promised, offered 2 or more types of pizza crust, delivered steaming hot pizza, and did not offer a money-back guarantee which was favored by each of the two purchase frequency groups. The results from this study suggested that there was an opportunity to increase market share and profit by improving operations so that customers can receive discount and money-back guarantee simultaneously, and by reducing price, delivery time.

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Relationship between the Sample Quantiles and Sample Quantile Ranks (표본분위수와 표본분위의 관계)

  • Ahn, Sung-Jin
    • Communications for Statistical Applications and Methods
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    • v.18 no.6
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    • pp.707-716
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    • 2011
  • Quantiles and quantile ranks(or plotting positions) are widely used in academia and industry. Sample quantile methods and sample quantile methods implemented in some major statistical software are at least seven, respectively. Small looking differences between the methods can make big differences in outcomes that result from decisions based on them. We discussed the characteristics and differences of the basic plotting position using the empirical cumulative probability and the six plotting positions derived from the suggestion of Blom (1958). After discussing the characteristics and differences of seven quantile methods used in the some major statistical software, we suggested a general expression covering all seven quantile methods. Using the insight obtained from the general expression, we proposed four propositions that make it possible to find the plotting position method that correspond to each of the seven quantile methods. These correspondences may help us to understand and apply quantile methodology.

Relation of Various Parameters Used to Estimate Cardiac Vagal Activity and Validity of pNN50 in Anesthetized Humans

  • Lee, Jae Ho;Huh, In Young;Lee, Jae Min;Lee, Hyung Kwan;Han, Il Sang;Kang, Ho Jun
    • Kosin Medical Journal
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    • v.33 no.3
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    • pp.369-379
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    • 2018
  • Objectives: Analysis of heart rate variability (HRV) has been used as a measure of cardiac autonomic function. According to the pNN50 statistic, the percentage of differences between successive normal RR intervals (RRI) that exceed 50 ms, has been known to reflect cardiac vagal modulation. Relatively little is known about the validity of pNN50 during general anesthesia (GA). Therefore, we evaluated the correlation of pNN50 with other variables such as HF, RMSSD, SD1 of HRV reflecting the vagal tone, and examined the validity of pNN50 in anesthetized patients. Methods: We assessed changes in RRI, pNN50, root mean square of successive differences of RRI (RMSSD), high frequency (HF) and standard deviation 1 (SD1) of $Poincar{\acute{e}}$ plots after GA using sevoflurane anesthesia. We also calculated the probability distributions for the family of pNNx statistics (x: 2-50 ms). Results: All HRV variables were significantly decreased during GA. HF power was not correlated with pNN50 during GA (r = 0.096, P = 0.392). Less than pNN47 was shown to have a correlation with other variables. Conclusions: These data suggest that pNN50 can not reflect the level of vagal tone during GA.

Studying the Possibility of Puzzle Based Learning for Informatics Gifted Elementary Student Education (초등정보영재 교육을 위한 퍼즐 기반 학습 가능성 탐색)

  • Choi, JeongWon;Lee, Eunkyoung;Lee, YoungJun
    • The Journal of Korean Association of Computer Education
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    • v.16 no.5
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    • pp.9-16
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    • 2013
  • Computational thinking is an ability to resolve problems that may be applied to the various real world problems and is regarded as the core of computer science. Computational thinking may be improved through experiences of analyzing problems and of selecting, applying, and modeling strategies appropriate for problem-solving. In order to enhance computational thinking of learners, it is important to provide experiences of solving various problems. This study designed puzzle based learning in order to educate learners principles of problem solving, let them have experiences of interest and insight, and provide them with problem solving experiences. The puzzle questions used for learning were classified into six types - constraints, optimization, probability, statistics, pattern recognition, and strategies. These questions were applied to Informatics gifted elementary students and, after their education, their computational thinking and problem solving inventory significantly improved.

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A comparison of deep-learning models to the forecast of the daily solar flare occurrence using various solar images

  • Shin, Seulki;Moon, Yong-Jae;Chu, Hyoungseok
    • The Bulletin of The Korean Astronomical Society
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    • v.42 no.2
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    • pp.61.1-61.1
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    • 2017
  • As the application of deep-learning methods has been succeeded in various fields, they have a high potential to be applied to space weather forecasting. Convolutional neural network, one of deep learning methods, is specialized in image recognition. In this study, we apply the AlexNet architecture, which is a winner of Imagenet Large Scale Virtual Recognition Challenge (ILSVRC) 2012, to the forecast of daily solar flare occurrence using the MatConvNet software of MATLAB. Our input images are SOHO/MDI, EIT $195{\AA}$, and $304{\AA}$ from January 1996 to December 2010, and output ones are yes or no of flare occurrence. We consider other input images which consist of last two images and their difference image. We select training dataset from Jan 1996 to Dec 2000 and from Jan 2003 to Dec 2008. Testing dataset is chosen from Jan 2001 to Dec 2002 and from Jan 2009 to Dec 2010 in order to consider the solar cycle effect. In training dataset, we randomly select one fifth of training data for validation dataset to avoid the over-fitting problem. Our model successfully forecasts the flare occurrence with about 0.90 probability of detection (POD) for common flares (C-, M-, and X-class). While POD of major flares (M- and X-class) forecasting is 0.96, false alarm rate (FAR) also scores relatively high(0.60). We also present several statistical parameters such as critical success index (CSI) and true skill statistics (TSS). All statistical parameters do not strongly depend on the number of input data sets. Our model can immediately be applied to automatic forecasting service when image data are available.

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A Study on the Characteristics of Opinion Retrieval Using Term Statistical Analysis in Opinion Documents (의견 문서의 단어 통계 분석을 통한 의견 검색 특성에 관한 연구)

  • Han, Kyoung-Soo
    • Journal of the Korea Society of Computer and Information
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    • v.15 no.11
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    • pp.21-29
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    • 2010
  • Opinion retrieval which searches the opinions expressed in documents by users cannot outperform significantly yet traditional topical retrieval which searches the facts. Therefore, the focus of this paper is to identify the statistical characteristics which can be applied to opinion retrieval by comparing and analyzing the term statistics of opinion and non-opinion documents in the blog domain. The TREC Blogs06 collection and 150 TREC topics are used in the experiments. The difference between term probability distributions in opinion documents is measured by JS divergence, and the difference according to the topic types and topic domains is also investigated. Moreover, the term probabilities of opinion terms are analyzed comparatively. The main findings of this study include the following: it is necessary to consider the topic-specific characteristics for the opinion detection; it is effective to extract positive and negative opinion terms according to the topics; the topic types are complementary to the topic domains; and special attention has to be given to the usage of the positive opinion terms.

Probabilistic Modeling of Photovoltaic Power Systems with Big Learning Data Sets (대용량 학습 데이터를 갖는 태양광 발전 시스템의 확률론적 모델링)

  • Cho, Hyun Cheol;Jung, Young Jin
    • Journal of the Korean Institute of Intelligent Systems
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    • v.23 no.5
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    • pp.412-417
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    • 2013
  • Analytical modeling of photovoltaic power systems has been receiving significant attentions in recent years in that it is easy to apply for prediction of its dynamics and fault detection and diagnosis in advanced engineering technologies. This paper presents a novel probabilistic modeling approach for such power systems with a big data sequence. Firstly, we express input/output function of photovoltaic power systems in which solar irradiation and ambient temperature are regarded as input variable and electric power is output variable respectively. Based on this functional relationship, conditional probability for these three random variables(such as irradiation, temperature, and electric power) is mathematically defined and its estimation is accomplished from ratio of numbers of all sample data to numbers of cases related to two input variables, which is efficient in particular for a big data sequence of photovoltaic powers systems. Lastly, we predict the output values from a probabilistic model of photovoltaic power systems by using the expectation theory. Two case studies are carried out for testing reliability of the proposed modeling methodology in this paper.

Analysis of the contents of Practice and Synthetic Application area in Yanbian Textbooks (중국 연변 수학 교과서의 실천과 종합응용 영역에 나타난 학습내용 분석)

  • Lee, Daehyun
    • Journal of the Korean School Mathematics Society
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    • v.16 no.2
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    • pp.319-335
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    • 2013
  • Chinese mathematical curriculum is divided 4 areas(number and algebra, space and figure, statistics and probability, practice and synthetic application). The purpose of this paper is to analyze the contents of the practice and synthetic application in yanbian elementary textbook. For this, 12-textbook which was published in yeonbeon a publishing company is analyze by topic, mathematical process, area of content and mathematical activity. mathematical process The following results have been drawn from this study. First, contextual backgrounds of practice are restricted in classroom. The contents of synthetic application are limited in connection of mathematical areas. Mathematical problem solving is a main in mathematical process, whereas reasoning activity is a few. Mathematical experience activity is a main in mathematical process, whereas synthetic activity is a few. We can use the suggestions of this paper for development of textbook and the contents of mathematical process.

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