• 한국산학기술학회논문지
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• 제10권6호
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• pp.1424-1432
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• 2009

충수돌기염 환자의 LoS(Length of Stay)를 예측하는 것은 병상의 운영에 적지 않은 영향을 준다. 본 논문에서는 Neural Networks와 Decision Tree를 이용하여 LoS와 연관이 높은 입력변수들을 찾아 그 의미를 분석하며, 찾아낸 입력변수들을 이용하여 다양한 LoS 예측 모형을 개발하고 그 성능을 비교하였다. 모형의 예측 정확성을 높이기 위하여 Bagging과 Boosting 등의 Ensemble 기법도 적용하였다. 실험 결과, Decision Tree 모형이 Neural Networks 모형보다 좀 더 적은 수의 속성을 가지고도 거의 통일한 예측력을 보였으며, Ensemble 기법 중에서는 Bagging 기법이 Boosting 기법보다 좋은 결과를 보여주었다. 의사결정나무 기법은 Neural Networks 기법에 비해 설명력이 있으며, 충수돌기염의 LoS 예측에 매우 효과적이었고, 중요 입력 변수의 선정에도 좋은 결과를 보여줌에 따라 향후 적극적인 기법의 도입이 필요하다고 할 수 있다.

• Journal of the Korean Data and Information Science Society
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• 제23권2호
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• pp.299-307
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• 2012

데이터마이닝은 주어진 데이터베이스에서 항목간의 흥미로운 관계를 찾아내는 기법으로서 의사결정나무는 데이터마이닝의 대표적인 알고리즘이라고 할 수 있다. 의사결정나무는 관심대상이 되는 집단을 몇 개의 소집단으로 분류하거나 예측을 수행하는 방법이다. 일반적으로 연구자가 의사결정나무 모형을 생성 할 때 모형 생성의 기준 및 입력 변수의 수에 따라 복잡한 모형이 생성되기도 한다. 특히 의사결정나무 모형에서 입력 변수의 수가 많을 경우 생성된 모형은 복잡한 형태가 될 수 있고, 모형 분석이 어려울 수도 있다. 만일 입력변수에서 주변조건부 변수 (매개변수, 외적변수)가 존재한다면 이 입력변수는 직접적인 관련성이 없는 것으로 판단한다. 이에 본 논문에서는 주변조건부 변수를 고려하여 의사결정나무모형을 생성하는 방법을 제시하고 그 효율성을 파악하기 위하여 실제 자료에 적용하고자 한다.

• 한국컴퓨터산업학회논문지
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• 제2권2호
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• pp.195-202
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• 2001

본 논문에서는 한국어 음소가 좌, 우 음소에 따라 발음 방식이 달라질 때 매 음소를 모델링 하는 방법에 관한 연구를 수행한다. 이를 위해 유니트 감소 알고리즘과 결정 트리(Decision Tree)를 사용하는 방법을 사용하여 비교 연구한다. 유니트 감소 알고리즘은 통계적 특성만을 이용한 알고리즘이며 결정 트리 모델링 방식은 한국어 음운정보와 통계적 정보를 이용하여 문맥종속 음소를 분류하는 방식이다. 특히 본 논문에서는 결정 트리를 사용하여 문맥종속 음소를 분류하는 것에 대하여 상세히 기술한다. 마지막으로 결정 트리를 사용하여 분류된 문맥종속 음소의 성능을 실험하였다.

• ETRI Journal
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• 제29권4호
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• pp.527-529
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• 2007

In this paper, a decision-tree-based Markov model for phrase break prediction is proposed. The model takes advantage of the non-homogeneous-features-based classification ability of decision tree and temporal break sequence modeling based on the Markov process. For this experiment, a text corpus tagged with parts-of-speech and three break strength levels is prepared and evaluated. The complex feature set, textual conditions, and prior knowledge are utilized; and chunking rules are applied to the search results. The proposed model shows an error reduction rate of about 11.6% compared to the conventional classification model.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 춘계 학술발표회 초청강연 및 논문집
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• pp.1365-1371
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• 2008

Based on the data obtained from field investigation and soil testing to slope hazards occurrence section and non-occurrence section in gneiss area, a prediction technique was developed by the use of a decision tree model. The slope hazards data of Seoul and Kyonggi Province were 104 sections in gneiss area. The number of data applied in developing prediction model was 61 sections except a vacant value. The statistical analyses using the decision tree model were applied to the entrophy index. As the results of analyses, a slope angle, a degree of saturation and an elevation were selected as the classification standard. The prediction model of decision tree using entrophy index is most likely accurate. The classification standard of the selected prediction model is composed of the slope angle, the degree of saturation and the elevation from the first choice stage. The classification standard values of the slope angle, the degree of saturation and elevation are $17.9^{\circ}$, 52.1% and 320m, respectively.

• 대한간호학회지
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• 제36권4호
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• pp.662-670
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• 2006

Purpose. This study was performed to develop and test a decision-tree model of treatment-seeking behaviors about when Korean patients visit a doctor after experiencing stroke symptoms. Methods. The study used methodological triangulation. The model was developed based on qualitative data collected from in-depth interviews with 18 stroke patients. The model was tested using quantitative data collected from interviews and a structured questionnaire involving 150 stroke patients. The predictability of the decision-tree model was quantified as the proportion of participants who followed the pathway predicted by the model. Results. Decision outcomes of the model were categorized into immediate and delayed treatment-seeking behavior. The model was influenced by lowered consciousness, social-group influences, perceived seriousness of symptoms, past history of hypertension or stroke, and barriers to hospital visits. The predictability of the model was found to be 90.7%. Conclusions. The results from this study can help healthcare personnel understand the education needs of stroke patients regarding treatment-seeking behaviors, and hence aid in the development of educational strategies for stroke patients.

• Journal of Information Processing Systems
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• 제19권5호
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• pp.652-662
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• 2023

Identifying highly discriminating genes is a critical step in tumor recognition tasks based on microarray gene expression profile data and machine learning. Gene selection based on tree models has been the subject of several studies. However, these methods are based on a single-tree model, often not robust to ultra-highdimensional microarray datasets, resulting in the loss of useful information and unsatisfactory classification accuracy. Motivated by the limitations of single-tree-based gene selection, in this study, ensemble gene selection methods based on multiple-tree models were studied to improve the classification performance of tumor identification. Specifically, we selected the three most representative tree models: ID3, random forest, and gradient boosting decision tree. Each tree model selects top-n genes from the microarray dataset based on its intrinsic mechanism. Subsequently, three ensemble gene selection methods were investigated, namely multipletree model intersection, multiple-tree module union, and multiple-tree module cross-union, were investigated. Experimental results on five benchmark public microarray gene expression datasets proved that the multiple tree module union is significantly superior to gene selection based on a single tree model and other competitive gene selection methods in classification accuracy.

• International Journal of Computer Science & Network Security
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• 제21권7호
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• pp.56-62
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• 2021

The surge in generic attacks execution against cipher text on the computer network has led to the continuous advancement of the mechanisms to protect information integrity and confidentiality. The implementation of explicit decision tree machine learning algorithm is reported to accurately classifier generic attacks better than some multi-classification algorithms as the multi-classification method suffers from detection oversight. However, there is a need to improve the accuracy and reduce the false alarm rate. Therefore, this study aims to improve generic attack classification by implementing two hybridized decision tree algorithms namely Naïve Bayes Decision tree (NBTree) and Logistic Model tree (LMT). The proposed hybridized methods were developed using the 10-fold cross-validation technique to avoid overfitting. The generic attack detector produced a 99.8% accuracy, an FPR score of 0.002 and an MCC score of 0.995. The performances of the proposed methods were better than the existing decision tree method. Similarly, the proposed method outperformed multi-classification methods for detecting generic attacks. Hence, it is recommended to implement hybridized decision tree method for detecting generic attacks on a computer network.

• Journal of Information Technology Applications and Management
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• 제15권4호
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• pp.21-36
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• 2008

As the great disturbance from abusing credit cards in Korea becomes stabilized, credit card companies need to interpret credit-card delinquents classification models from the viewpoint of profit. However, hit ratio which has been used as a measure of goodness of classification models just tells us how much correctly they classified rather than how much profits can be obtained as a result of using classification models. In this research, we tried to develop a new utility-based measure from the viewpoint of profit and then used this new measure to analyze two classification models(Neural Networks and Decision Tree models). We found that the hit ratio of neural model is higher than that of decision tree model, but the utility value of decision tree model is higher than that of neural model. This experiment shows the importance of utility based measure for credit-card delinquents classification models. We expect this new measure will contribute to increasing profits of credit card companies.

• 한국도로학회논문집
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• 제16권4호
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• pp.127-134
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• 2014

PURPOSES : To operate more efficient traffic management system, it is utmost important to detect the change in congestion level on a freeway segment rapidly and reliably. This study aims to develop classification method of congestion change type. METHODS: This research proposes two classification methods to capture the change of the congestion level on freeway segments using the dedicated short range communication (DSRC) data and the vehicle detection system (VDS) data. For developing the classification methods, the decision tree models were employed in which the independent variable is the change in congestion level and the covariates are the DSRC and VDS data collected from the freeway segments in Korea. RESULTS : The comparison results show that the decision tree model with DSRC data are better than the decision tree model with VDS data. Specifically, the decision tree model using DSRC data with better fits show approximately 95% accuracies. CONCLUSIONS : It is expected that the congestion change type classified using the decision tree models could play an important role in future freeway traffic management strategy.