• Title/Summary/Keyword: sampling and classification

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Self-Sampling Versus Physicians' Sampling for Cervical Cancer Screening - Agreement of Cytological Diagnoses

  • Othman, Nor Hayati;Zaki, Fatma Hariati Mohamad;Hussain, Nik Hazlina Nik;Yusoff, Wan Zahanim Wan;Ismail, Pazuddin
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.7
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    • pp.3489-3494
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    • 2016
  • Background: A major problem with cervical cancer screening in countries which have no organized national screening program for cervical cancer is sub-optimal participation. Implementation of self-sampling method may increase the coverage. Objective: We determined the agreement of cytological diagnoses made on samples collected by women themselves (self-sampling) versus samples collected by physicians (Physician sampling). Materials and Methods: We invited women volunteers to undergo two procedures; cervical self-sampling using the Evalyn brush and physician sampling using a Cervex brush. The women were shown a video presentation on how to take their own cervical samples before the procedure. The samples taken by physicians were taken as per routine testing (Gold Standard). All samples were subjected to Thin Prep monolayer smears. The diagnoses made were according to the Bethesda classification. The results from these two sampling methods were analysed and compared. Results: A total of 367 women were recruited into the study, ranging from 22 to 65 years age. There was a significant good agreement of the cytological diagnoses made on the samples from the two sampling methods with the Kappa value of 0.568 (p=0.040). Using the cytological smears taken by physicians as the gold standard, the sensitivity of self-sampling was 71.9% (95% CI:70.9-72.8), the specificity was 86.6% (95% CI:85.7-87.5), the positive predictive value was 74.2% (95% CI:73.3-75.1) and the negative predictive value was 85.1% (95% CI: 84.2-86.0). Self-sampling smears (22.9%) allowed detection of micro-organisms better than physicians samples (18.5%). Conclusions: This study shows that samples taken by women themselves (self-sampling) and physicians have good diagnostic agreement. Self-sampling could be the method of choice in countries in which the coverage of women attending clinics for screening for cervical cancer is poor.

A Three-Step Preprocessing Algorithm for Enhanced Classification of E-Mail Recommendation System (이메일 추천 시스템의 분류 향상을 위한 3단계 전처리 알고리즘)

  • Jeong Ok-Ran;Cho Dong-Sub
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.54 no.4
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    • pp.251-258
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    • 2005
  • Automatic document classification may differ significantly according to the characteristics of documents that are subject to classification, as well as classifier's performance. This research identifies e-mail document's characteristics to apply a three-step preprocessing algorithm that can minimize e-mail document's atypical characteristics. In the first 5go, uncertain based sampling algorithm that used Mean Absolute Deviation(MAD), is used to address the question of selection learning document for the rule generation at the time of classification. In the subsequent stage, Weighted vlaue assigning method by attribute is applied to increase the discriminating capability of the terms that appear on the title on the e-mail document characteristic level. in the third and last stage, accuracy level during classification by each category is increased by using Naive Bayesian Presumptive Algorithm's Dynamic Threshold. And, we implemented an E-Mail Recommendtion System using a three-step preprocessing algorithm the enable users for direct and optimal classification with the recommendation of the applicable category when a mail arrives.

Target Classification in Sparse Sampling Acoustic Sensor Networks using DTW-Cosine Algorithm (저비율 샘플링 음향 센서네트워크에서 DTW-Cosine 알고리즘을 이용한 목표물 식별기법)

  • Kim, Young-Soo;Kang, Jong-Gu;Kim, Dae-Young
    • Journal of KIISE:Computing Practices and Letters
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    • v.14 no.2
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    • pp.221-225
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    • 2008
  • In this paper, to avoid the frequency analysis requiring a high sampling rate, time-warped similarity measure algorithms, which are able to classify objects even with a low-rate sampling rate as time- series methods, are presented and proposed the DTW-Cosine algorithm, as the best classifier among them in wireless sensor networks. Two problems, local time shifting and spatial signal variation, should be solved to apply the time-warped similarity measure algorithms to wireless sensor networks. We find that our proposed algorithm can overcome those problems very efficiently and outperforms the other algorithms by at least 10.3% accuracy.

A Study on Incremental Learning Model for Naive Bayes Text Classifier (Naive Bayes 문서 분류기를 위한 점진적 학습 모델 연구)

  • 김제욱;김한준;이상구
    • The Journal of Information Technology and Database
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    • v.8 no.1
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    • pp.95-104
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    • 2001
  • In the text classification domain, labeling the training documents is an expensive process because it requires human expertise and is a tedious, time-consuming task. Therefore, it is important to reduce the manual labeling of training documents while improving the text classifier. Selective sampling, a form of active learning, reduces the number of training documents that needs to be labeled by examining the unlabeled documents and selecting the most informative ones for manual labeling. We apply this methodology to Naive Bayes, a text classifier renowned as a successful method in text classification. One of the most important issues in selective sampling is to determine the criterion when selecting the training documents from the large pool of unlabeled documents. In this paper, we propose two measures that would determine this criterion : the Mean Absolute Deviation (MAD) and the entropy measure. The experimental results, using Renters 21578 corpus, show that this proposed learning method improves Naive Bayes text classifier more than the existing ones.

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The Development of Classification System of Medical Procedures in Korea (한국표준의료행위 분류체계 개발)

  • Park, Hyoung-Wook;Sohn, Myong-Sei;Kim, Han-Joong;Park, Eun-Cheol;Yu, Seung-Hum
    • Journal of Preventive Medicine and Public Health
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    • v.29 no.4 s.55
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    • pp.877-897
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    • 1996
  • In recent years, the Korean Medical Association has undertaken the feat of establishing the Korean Standard Terminology of Medical Procedures with the dedicated help of 32 medical academic societies. However, because the project is being conducted by several different circles, it has yet to see a clear system of classification. This thesis, therefore, proposes the three principles of scientific properties, usefulness and ideology as the basis for classification system and has developed the Classification System of Medical Procedures in Korea upon their foundation. The methodology and organization of this thesis as follows. First, by adopting scientific classification system of Feinstein(1988), an analysis of the classification systems of the medical procedures in the United States, Japan, Taiwan, WHO was carried out to reveal the framework and the basic principles in each system. Second, the direction of classification system has been constructed by applying the normative principle of medical field in order to show the future direction of the medical field and realize its ideology. Third, a finalized framework for the classification system will be presented as based on the direction of classification system. Of the three basis principles mentioned above, the analysis on the principles of usefulness was left out of this thesis due to the difficulty of establishing specific standards of analysis. The results of the study are as follows. The overall structure of the thesis is aimed at showing the 'Prevention-Therapy-Rehabilitation' quality of comprehensive health care and consists of six chapters; I. Prevention and Health Promotion II. Evaluation and Management III. Diagnostic Procedures IV. Endoscopy V. Therapeutic Procedures VI. Rehabilitation Chapter three Diagnostic Procedures is divided into four parts : Functional Diagnosis, Visual Diagnosis, Pathological Diagnosis, Biopsy and Sampling. Chapter five Therapeutic Procedures is divided into Psychiatry, Non-Invasive Therapy, Invasive Therapy, Anaesthesia and Radiation Oncology. Of these sub-divisions, Functional Diagnosis, Biopsy and Sampling, Endoscopy and Invasive Therapy employs the anatomical system of classification. On the other hand, Visual Diagnosis, Pathological Diagnosis, Anesthesia and Diagnostic Radiology, namely those divisions in which there is little or no overlapping in services with other divisions, used the classification system of its own division. The classification system introduced in this thesis can be further supplemented through the use of the cluster analysis by incorporating the advice and assistance of other specialists.

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A study on the modified hough transform for hangul feature extraction using generalized sampling rule (한글 특징점 추출을 위한 일반화된 표본화 알고리즘을 이용한 수정된 Hough Transform에 관한 연구)

  • 구하성;고형화
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.31B no.9
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    • pp.142-149
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    • 1994
  • Hangul is expressed by the basic elements, twenty-four characters. Because these characters are composed of a circle and lines, Hough transform(HT), which has a powerful performance on the noise in extracting lines, is introduced. Many difficulties often occur when the original HT is used to extract strokes and it's direction, position and length from handwritten Hangul characters. Original HT has eight direction selected as samples in the transformed image should be calculated for these eight directions. In this paper, the generalized sampling rule is suggested. According to the rule, those directions which are possible to a line are the only thing to be calculated. The experoment result turned out to be higher than the method that Chen suggested in sampling rate. Anogher experiment result is done on the 1800 handwritten Hangul characters that 10 persons wrote. By feature extracting the oritinal HT and sampling HT. And as a result of six type classification, the suggested method came out higher than original HT.

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A Sampling Design for Health Index Survey

  • Ryu, Jea-Bok;Lee, Kay-O;Kim, Young-Won
    • Communications for Statistical Applications and Methods
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    • v.9 no.2
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    • pp.565-576
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    • 2002
  • We propose a new sampling design for the 2001 Health Index Survey at Seoul. In this stratified two-stage sampling design, the ED(enumeration district) of 2000 Population and Housing Census is used as primary sampling unit and the Gu is used as stratification variable in order to obtain the sub-domain estimate for 25 Gu's as well as population estimate for Seoul. The sample ED's are systematically selected after the Ed's are ordered by location and property to obtain a representative sample. And also, the imputation methods for item nonresponses are suggested.

Effect of Prior Probabilities on the Classification Accuracy under the Condition of Poor Separability

  • Kim, Chang-Jae;Eo, Yang-Dam;Lee, Byoung-Kil
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.26 no.4
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    • pp.333-340
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    • 2008
  • This paper shows that the use of prior probabilities of the involved classes improve the accuracy of classification in case of poor separability between classes. Three cases of experiments are designed with two LiDAR datasets while considering three different classes (building, tree, and flat grass area). Moreover, random sampling method with human interpretation is used to achieve the approximate prior probabilities in this research. Based on the experimental results, Bayesian classification with the appropriate prior probability makes the improved classification results comparing with the case of non-prior probability when the ratio of prior probability of one class to that of the other is significantly different to 1.0.

THE CALIBRATION ESTIMATION USING TWO-STEP NEWTON'S ALGORITHM IN TWO-PHASE SAMPLING

  • Son, Chang-Kyoon;Yum, Joon-Keun
    • Journal of applied mathematics & informatics
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    • v.7 no.1
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    • pp.237-245
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    • 2000
  • In this paper, we consider to the adjustment weighting procedure in the two phase sampling scheme. In general, the unit nonresponses may be occured in the final survey operation. When the unit nonresponse be generated in survey, it is able to use the auxiliary variable for estimating of interest variable. In this viewpoint, we use the two kinds level of auxiliary variable, $X_{1k}$ and $X_{2k}$ for the calibration procedure. We proprose the two-step Newton's method in the calibration estimation procedure for the two phase sampling.