• 제목/요약/키워드: data classification

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Discriminant Analysis of Binary Data by Using the Maximum Entropy Distribution

  • Lee, Jung Jin;Hwang, Joon
    • Communications for Statistical Applications and Methods
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    • 제10권3호
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    • pp.909-917
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    • 2003
  • Although many classification models have been used to classify binary data, none of the classification models dominates all varying circumstances depending on the number of variables and the size of data(Asparoukhov and Krzanowski (2001)). This paper proposes a classification model which uses information on marginal distributions of sub-variables and its maximum entropy distribution. Classification experiments by using simulation are discussed.

분류 성능 향상을 위한 지역적 선형 재구축 기반 결측치 대치 (Missing Value Imputation based on Locally Linear Reconstruction for Improving Classification Performance)

  • 강필성
    • 대한산업공학회지
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    • 제38권4호
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    • pp.276-284
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    • 2012
  • Classification algorithms generally assume that the data is complete. However, missing values are common in real data sets due to various reasons. In this paper, we propose to use locally linear reconstruction (LLR) for missing value imputation to improve the classification performance when missing values exist. We first investigate how much missing values degenerate the classification performance with regard to various missing ratios. Then, we compare the proposed missing value imputation (LLR) with three well-known single imputation methods over three different classifiers using eight data sets. The experimental results showed that (1) any imputation methods, although some of them are very simple, helped to improve the classification accuracy; (2) among the imputation methods, the proposed LLR imputation was the most effective over all missing ratios, and (3) when the missing ratio is relatively high, LLR was outstanding and its classification accuracy was as high as the classification accuracy derived from the compete data set.

Filtering Effect in Supervised Classification of Polarimetric Ground Based SAR Images

  • Kang, Moon-Kyung;Kim, Kwang-Eun;Cho, Seong-Jun;Lee, Hoon-Yol;Lee, Jae-Hee
    • 대한원격탐사학회지
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    • 제26권6호
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    • pp.705-719
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    • 2010
  • We investigated the speckle filtering effect in supervised classification of the C-band polarimetric Ground Based SAR image data. Wishart classification method was used for the supervised classification of the polarimetric GB-SAR image data and total of 6 kinds of speckle filters were applied before supervised classification, which are boxcar, Gaussian, Lopez, IDAN, the refined Lee, and the refined Lee sigma filters. For each filters, we changed the filtering kernel size from $3{\times}3$ to $9{\times}9$ to investigate the filtering size effect also. The refined Lee filter with the kernel size of bigger than $5{\times}5$ showed the best result for the Wishart supervised classification of polarimetric GB-SAR image data. The result also showed that the type of trees could be discriminated by Wishart supervised classification of polarimetric GB-SAR image data.

Design and Implementation of the Ensemble-based Classification Model by Using k-means Clustering

  • Song, Sung-Yeol;Khil, A-Ra
    • 한국컴퓨터정보학회논문지
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    • 제20권10호
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    • pp.31-38
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    • 2015
  • In this paper, we propose the ensemble-based classification model which extracts just new data patterns from the streaming-data by using clustering and generates new classification models to be added to the ensemble in order to reduce the number of data labeling while it keeps the accuracy of the existing system. The proposed technique performs clustering of similar patterned data from streaming data. It performs the data labeling to each cluster at the point when a certain amount of data has been gathered. The proposed technique applies the K-NN technique to the classification model unit in order to keep the accuracy of the existing system while it uses a small amount of data. The proposed technique is efficient as using about 3% less data comparing with the existing technique as shown the simulation results for benchmarks, thereby using clustering.

GPU를 이용한 DNA 컴퓨팅 기반 패턴 분류기의 효율적 구현 (Efficient Implementing of DNA Computing-inspired Pattern Classifier Using GPU)

  • 최선욱;이종호
    • 전기학회논문지
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    • 제58권7호
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    • pp.1424-1434
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    • 2009
  • DNA computing-inspired pattern classification based on the hypernetwork model is a novel approach to pattern classification problems. The hypernetwork model has been shown to be a powerful tool for multi-class data analysis. However, the ordinary hypernetwork model has limitations, such as operating sequentially only. In this paper, we propose a efficient implementing method of DNA computing-inspired pattern classifier using GPU. We show simulation results of multi-class pattern classification from hand-written digit data, DNA microarray data and 8 category scene data for performance evaluation. and we also compare of operation time of the proposed DNA computing-inspired pattern classifier on each operating environments such as CPU and GPU. Experiment results show competitive diagnosis results over other conventional machine learning algorithms. We could confirm the proposed DNA computing-inspired pattern classifier, designed on GPU using CUDA platform, which is suitable for multi-class data classification. And its operating speed is fast enough to comply point-of-care diagnostic purpose and real-time scene categorization and hand-written digit data classification.

마이크로어레이 자료에서 서포트벡터머신과 데이터 뎁스를 이용한 분류방법의 비교연구 (A comparison study of classification method based of SVM and data depth in microarray data)

  • 황진수;김지연
    • Journal of the Korean Data and Information Science Society
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    • 제20권2호
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    • pp.311-319
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    • 2009
  • 군집과 분류분석에서 L1 데이터 뎁스를 이용한 DDclust와 DDclass라고 불리는 로버스트한 방법이 Jornsten (2004)에 의하여 제안되었다. SVM-기반방법이 많이 사용되나 이상치가 있는 경우에는 약간의 문제가 있다. 유전자 자료에서는 유전자 수가 많기 때문에 적절한 유전자 선택과정이 필요하다. 따라서 적절한 유전자 또는 유전자 군집을 선택하여 분류에 이용하면 분류의 성능을 향상시킬 수 있다. 이러한 관점에서 뎁스 기반 분류방법과 SVM-기반 분류방법을 비교 연구하여 그 성능을 비교 하였다.

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Automated Training from Landsat Image for Classification of SPOT-5 and QuickBird Images

  • Kim, Yong-Min;Kim, Yong-Il;Park, Wan-Yong;Eo, Yang-Dam
    • 대한원격탐사학회지
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    • 제26권3호
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    • pp.317-324
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    • 2010
  • In recent years, many automatic classification approaches have been employed. An automatic classification method can be effective, time-saving and can produce objective results due to the exclusion of operator intervention. This paper proposes a classification method based on automated training for high resolution multispectral images using ancillary data. Generally, it is problematic to automatically classify high resolution images using ancillary data, because of the scale difference between the high resolution image and the ancillary data. In order to overcome this problem, the proposed method utilizes the classification results of a Landsat image as a medium for automatic classification. For the classification of a Landsat image, a maximum likelihood classification is applied to the image, and the attributes of ancillary data are entered as the training data. In the case of a high resolution image, a K-means clustering algorithm, an unsupervised classification, was conducted and the result was compared to the classification results of the Landsat image. Subsequently, the training data of the high resolution image was automatically extracted using regular rules based on a RELATIONAL matrix that shows the relation between the two results. Finally, a high resolution image was classified and updated using the extracted training data. The proposed method was applied to QuickBird and SPOT-5 images of non-accessible areas. The result showed good performance in accuracy assessments. Therefore, we expect that the method can be effectively used to automatically construct thematic maps for non-accessible areas and update areas that do not have any attributes in geographic information system.

The Audio Signal Classification System Using Contents Based Analysis

  • Lee, Kwang-Seok;Kim, Young-Sub;Han, Hag-Yong;Hur, Kang-In
    • Journal of information and communication convergence engineering
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    • 제5권3호
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    • pp.245-248
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    • 2007
  • In this paper, we research the content-based analysis and classification according to the composition of the feature parameter data base for the audio data to implement the audio data index and searching system. Audio data is classified to the primitive various auditory types. We described the analysis and feature extraction method for the feature parameters available to the audio data classification. And we compose the feature parameters data base in the index group unit, then compare and analyze the audio data centering the including level around and index criterion into the audio categories. Based on this result, we compose feature vectors of audio data according to the classification categories, and simulate to classify using discrimination function.

자료변환 기반 특징과 다중 분류자를 이용한 다중시기 SAR자료의 분류 (Classification of Multi-temporal SAR Data by Using Data Transform Based Features and Multiple Classifiers)

  • 유희영;박노욱;홍석영;이경도;김예슬
    • 대한원격탐사학회지
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    • 제31권3호
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    • pp.205-214
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    • 2015
  • 이 연구에서는 자료변환기법을 이용해 추출된 여러 특징과 다양한 분류방법론을 결합하여 다중시기 SAR 자료를 위한 새로운 토지피복 분류기법을 제안하였다. 먼저, 다중시기 SAR 자료로부터 원본자료와는 다른 새로운 정보를 추출하기 위해 주성분분석과 3차원 웨이블렛 변환을 이용한 자료변환을 수행하였다. 그리고 나서 최대우도법 분류자, 신경망, support vector machine을 포함한 세 가지 다른 분류자를 변환된 특징자료들과 원본 후방산란계수 자료를 포함한 세가지 자료에 적용하여 다양한 초기 분류 결과를 얻도록 한다. 이후 다수결규칙을 통해 모든 초기결과를 결합하여 최종 분류 결과를 생성하게 된다. 다중시기 ENVISAT ASAR 자료를 이용한 사례연구에서 모든 초기 결과는 사용한 특징자료와 분류자의 종류에 따라 매우 다양한 분류정확도를 보였다. 이러한 9개의 초기 분류 결과를 결합한 최종 분류 결과는 가장 높은 분류 정확도를 보여주고 있는데, 이는 각 초기 분류 결과가 토지피복을 결정하기 위한 상호 보완적인 정보를 제공하기 때문이다. 이 연구에서의 분류정확도 향상은 주로 자료변환을 통해 얻어진 각기 다른 특징자료와 다른 분류자를 결합에 의한 다양성 확보에서 기인한다. 그러므로 이 연구에서 제안한 토지피복 분류방법론은 다중시기 SAR자료의 분류에 효과적으로 적용가능하며, 또한 다중센서 원격탐사 자료융합으로 확장이 가능하다.

대학생이 과학 관련 과제에서 사용한 분류 전략의 미시발생적 분석 (A Microgenetic Analysis on the Classification Strategy Used in Tasks Related to Science by College Students)

  • 최현동
    • 대한지구과학교육학회지
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    • 제4권2호
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    • pp.151-165
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    • 2011
  • Following a microgenetic design, this study was analysed the characteristic and the change of classification strategy that appear in college students' classification activity. The 4 tasks were developed for classification activity; a shell as a familiar real things, an animal fossil as a unfamiliar real things, a snow flake as a familiar picture cards and galaxy as a unfamiliar picture card. Achieved study to 6 college students who major in elementary education. Data were collected by interview with subjects, subject's classification schema, investigator's observation of subject's activity, and videotaped that record subject's subject classification process over an extended period of 6 times. Result proved in this study is as following. In the 6 times of the data collection procedures, a strategy F identifying concrete attribution of classification objects and a more detailed strategy X3 combining qualitative, spatial and dimensional attribution were found and more frequently used in both groups of college students which reported a classification process and did not report the process. While discovery and absorption of both a concrete classification strategy and a detailed classification strategy were rapidly developed in the reporting group, they were gradually developed in the non-reporting group. In addition to this, as the data collection procedures were progressing, the college students were familiar with change factors of classification tasks and in the case of pictures the classification strategy showed more desirable changes.