• Title/Summary/Keyword: Bias Training

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The Effect of Job Training in Korea on Employment and Wage (직업훈련의 취업 및 임금효과)

  • Kang, Soon-Hie;Nho, Heung-Sung
    • Journal of Labour Economics
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    • v.23 no.2
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    • pp.127-151
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    • 2000
  • The empirical study that used the logit model and the Heckman's selection bias model based upon 'Korea Labor & Income Panel Study' shows that the experience of job training has a positive effect on the probability of employment, as well as on the wage increase. The analysis also sheds light on the effect on employment with wage workers who experienced job training. When the discouraged unemployed are not classified as labor force participants, that is the unemployed, and the industrial dummy variables are excluded, logit estimation shows that training program in the public sector, not in the private sector, significantly increases their employment probability. However when these same workers are classified as the unemployed and the industrial dummies are included, logit estimation shows that public and private training programs has no effect on their employability.

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Lagged Cross-Correlation of Probability Density Functions and Application to Blind Equalization

  • Kim, Namyong;Kwon, Ki-Hyeon;You, Young-Hwan
    • Journal of Communications and Networks
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    • v.14 no.5
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    • pp.540-545
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    • 2012
  • In this paper, the lagged cross-correlation of two probability density functions constructed by kernel density estimation is proposed, and by maximizing the proposed function, adaptive filtering algorithms for supervised and unsupervised training are also introduced. From the results of simulation for blind equalization applications in multipath channels with impulsive and slowly varying direct current (DC) bias noise, it is observed that Gaussian kernel of the proposed algorithm cuts out the large errors due to impulsive noise, and the output affected by the DC bias noise can be effectively controlled by the lag ${\tau}$ intrinsically embedded in the proposed function.

Fast Speaker Adaptation and Environment Compensation Based on Eigenspace-based MLLR (Eigenspace-based MLLR에 기반한 고속 화자적응 및 환경보상)

  • Song Hwa-Jeon;Kim Hyung-Soon
    • MALSORI
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    • no.58
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    • pp.35-44
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    • 2006
  • Maximum likelihood linear regression (MLLR) adaptation experiences severe performance degradation with very tiny amount of adaptation data. Eigenspace- based MLLR, as an alternative to MLLR for fast speaker adaptation, also has a weak point that it cannot deal with the mismatch between training and testing environments. In this paper, we propose a simultaneous fast speaker and environment adaptation based on eigenspace-based MLLR. We also extend the sub-stream based eigenspace-based MLLR to generalize the eigenspace-based MLLR with bias compensation. A vocabulary-independent word recognition experiment shows the proposed algorithm is superior to eigenspace-based MLLR regardless of the amount of adaptation data in diverse noisy environments. Especially, proposed sub-stream eigenspace-based MLLR with bias compensation yields 67% relative improvement with 10 adaptation words in 10 dB SNR environment, in comparison with the conventional eigenspace-based MLLR.

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Prediction of plasma etching using genetic-algorithm controlled backpropagation neural network

  • Kim, Sung-Mo;Kim, Byung-Whan
    • 제어로봇시스템학회:학술대회논문집
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    • 2003.10a
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    • pp.1305-1308
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    • 2003
  • A new technique is presented to construct a predictive model of plasma etch process. This was accomplished by combining a backpropagation neural network (BPNN) and a genetic algorithm (GA). The predictive model constructed in this way is referred to as a GA-BPNN. The GA played a role of controlling training factors simultaneously. The training factors to be optimized are the hidden neuron, training tolerance, initial weight magnitude, and two gradients of bipolar sigmoid and linear functions. Each etch response was optimized separately. The proposed scheme was evaluated with a set of experimental plasma etch data. The etch process was characterized by a $2^3$ full factorial experiment. The etch responses modeled are aluminum (A1) etch rate, silica profile angle, A1 selectivity, and dc bias. Additional test data were prepared to evaluate model appropriateness. The GA-BPNN was compared to a conventional BPNN. Compared to the BPNN, the GA-BPNN demonstrated an improvement of more than 20% for all etch responses. The improvement was significant in the case of A1 etch rate.

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Incremental Multi-classification by Least Squares Support Vector Machine

  • Oh, Kwang-Sik;Shim, Joo-Yong;Kim, Dae-Hak
    • Journal of the Korean Data and Information Science Society
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    • v.14 no.4
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    • pp.965-974
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    • 2003
  • In this paper we propose an incremental classification of multi-class data set by LS-SVM. By encoding the output variable in the training data set appropriately, we obtain a new specific output vectors for the training data sets. Then, online LS-SVM is applied on each newly encoded output vectors. Proposed method will enable the computation cost to be reduced and the training to be performed incrementally. With the incremental formulation of an inverse matrix, the current information and new input data are used for building another new inverse matrix for the estimation of the optimal bias and lagrange multipliers. Computational difficulties of large scale matrix inversion can be avoided. Performance of proposed method are shown via numerical studies and compared with artificial neural network.

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The Effect of Non-Pharmacological Intervention on Depressive Symptom in Elderly with Mild Cognitive Impairment : A Systematic Review of Randomized Controlled Trials (경도인지장애 노인의 우울증상을 위한 비약물적 중재 효과: 무작위 대조군 실험연구의 체계적 문헌고찰)

  • Jung, Jae-Hun
    • Journal of Industrial Convergence
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    • v.20 no.10
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    • pp.39-49
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    • 2022
  • The purpose of this study was to systematic review about randomized controlled trials the characteristics and effect of non-pharmacological intervention on depressive symptom in elderly with mild cognitive impairment. We searched studies published from January 2011 to July 2021 in 3 databases. A total 1,455 studies were found and included 11 studies in final analysis. Methodological quality was assessment with the Cochrane's RoB(risk of bias) tool. Geriatric Depression Scale(GDS) was the most used as the assessment tool for identifying the depressive symptom. Intervention were yoga, psychosocial intervention, cognitive training, health education, multi-component intervention, game training, aerobic/pulmonary physiotherapy, art therapy, music reminiscence activity, memory specificity training, cognitive stimulation therapy and SWTW(sleep well, think well) program. Among the intervention programs, yoga, multi-component intervention and game training were effective in improving depressive symptom. This study provided a clinical evidence for planning and implementing intervention on depressive symptom in elderly with mild cognitive impairment.

Training Techniques for Data Bias Problem on Deep Learning Text Summarization (딥러닝 텍스트 요약 모델의 데이터 편향 문제 해결을 위한 학습 기법)

  • Cho, Jun Hee;Oh, Hayoung
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.26 no.7
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    • pp.949-955
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    • 2022
  • Deep learning-based text summarization models are not free from datasets. For example, a summarization model trained with a news summarization dataset is not good at summarizing other types of texts such as internet posts and papers. In this study, we define this phenomenon as Data Bias Problem (DBP) and propose two training methods for solving it. The first is the 'proper nouns masking' that masks proper nouns. The second is the 'length variation' that randomly inflates or deflates the length of text. As a result, experiments show that our methods are efficient for solving DBP. In addition, we analyze the results of the experiments and present future development directions. Our contributions are as follows: (1) We discovered DBP and defined it for the first time. (2) We proposed two efficient training methods and conducted actual experiments. (3) Our methods can be applied to all summarization models and are easy to implement, so highly practical.

Tri-training algorithm based on cross entropy and K-nearest neighbors for network intrusion detection

  • Zhao, Jia;Li, Song;Wu, Runxiu;Zhang, Yiying;Zhang, Bo;Han, Longzhe
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.16 no.12
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    • pp.3889-3903
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    • 2022
  • To address the problem of low detection accuracy due to training noise caused by mislabeling when Tri-training for network intrusion detection (NID), we propose a Tri-training algorithm based on cross entropy and K-nearest neighbors (TCK) for network intrusion detection. The proposed algorithm uses cross-entropy to replace the classification error rate to better identify the difference between the practical and predicted distributions of the model and reduce the prediction bias of mislabeled data to unlabeled data; K-nearest neighbors are used to remove the mislabeled data and reduce the number of mislabeled data. In order to verify the effectiveness of the algorithm proposed in this paper, experiments were conducted on 12 UCI datasets and NSL-KDD network intrusion datasets, and four indexes including accuracy, recall, F-measure and precision were used for comparison. The experimental results revealed that the TCK has superior performance than the conventional Tri-training algorithms and the Tri-training algorithms using only cross-entropy or K-nearest neighbor strategy.

Correction of Mean and Extreme Temperature Simulation over South Korea Using a Trend-preserving Bias Correction Method (변동경향을 보존하는 편의보정기법을 이용한 우리나라의 평균 및 극한기온 모의결과 보정)

  • Jung, Hyun-Chae;Suh, Myoung-Seok
    • Atmosphere
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    • v.25 no.2
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    • pp.205-219
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    • 2015
  • In this study, the simulation results of temperature by regional climate model (Reg- CM4) over South Korea were corrected by Hempel et al. (2013)'s method (Hempel method), and evaluated with the observation data of 50 stations from Korea Meteorological Administration. Among the 30 years (1981~2010) of simulation data, 20 years (1981~2000) of simulation data were used as a training data, and the remnant 10 years (2001~2010) data were used for the evaluation of correction. In general, the Hempel method and parametric quantile mapping show a reasonable correction both in mean and extreme climate of temperature. As the results, the systematic underestimation of mean temperature was greatly reduced after bias correction by Hempel method. And the overestimation of extreme climate, such as the number of TN5% and freezing day, was significantly recovered. In addition to that, the Hempel method better preserved the temporal trend of simulated temperature than other bias correction methods, such as the quantile mapping. However, the overcorrection of the extreme climate related to the upper quantile, such as TX5% and hot days, resulted in the exaggeration of the simulation errors. In general, the Hempel method can reduce the systematic biases embedded in the simulation results preserving the temporal trend but it tends to overcorrect the non-linear biases, in particular, extreme climate related to the upper percentile.

The effects of coordinative locomotor training on balance in patients with chronic stroke: meta-analysis of studies in Korea (협응이동훈련이 만성 뇌졸중 환자의 균형에 미치는 효과: 국내연구의 메타분석)

  • Lim, Jae Heon;Park, Se Ju
    • Journal of Korean Physical Therapy Science
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    • v.27 no.2
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    • pp.36-47
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    • 2020
  • Background: This study purposed to provide meaningful information for the accumulation of knowledge on coordinative locomotor training in patients with stroke. Design: Meta-analysis. Methods: This study collected articles which the coordinative locomotor training in patients with stroke. For systematic meta-analysis, 6 articles were finally selected after searching based on the PICOSD criteria. This meta-analysis was conducted according to PRISMA guidelines. Randomized controlled trials were included and the risk of bias was evaluated for each study. Pooled standardized mean differences were calculated using a random effects model. To extract the effect size of each study, the R 3.5.3 software was used. Results: The meta-analysis showed that a total effects size was 1.23 indicating that coordinative locomotor training for patients with stroke had a maximum effect size. Conclusion: A meta-analysis is warranted for further research to determine the effects of coordinative locomotor training in patients with stroke on muscle strength, walking and range of motion.