• Journal of the Korean Data and Information Science Society
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• v.17 no.1
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• pp.19-30
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• 2006

The purpose of this article is to develop a program for teaching Type I and Type II errors in one sample. In this program, the concepts of two errors are visually explained, and the probabilities of two errors are also visually displayed as the rejection region changes or the sample size changes. Also, in this program, the power curve and the operating characteristic curve are visually displayed in terms of the parameter value of interest.

• Communications of the Korean Mathematical Society
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• v.15 no.2
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• pp.309-323
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• 2000

The purposes of this paper are to revise the definitions of Ishikawa and Mann type iterative processes with errors, to study the unique solution of the m-accretive operator equation x+Tx=f and the convergence problem of Ishikawa and Mann type iterative processes with errors for m-accretive mappings without the Lipschitz condition. The results presented in this paper improve, extend, and unify the corresponding results in [4, 7, 8, 12, 16] in more general setting.

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.47.5-47
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• 2002

Some integration methods for the linear subsystems are examined and which algorithm is optimal for real-time simulation is considered. First, a number of typical integration methods for a linear time-invariant system are given. Then, the dynamic errors are shown both from the point of view of characteristic root errors and transfer function errors. After that we compute the dynamic errors of integration and choose the appropriate method for each system.

• KIPS Transactions on Software and Data Engineering
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• v.9 no.7
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• pp.221-228
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• 2020

Part-of-Speech (POS) tagged corpus is a collection of electronic text in which each word is annotated with a tag as the corresponding POS and is widely used for various training data for natural language processing. The training data generally assumes that there are no errors, but in reality they include various types of errors, which cause performance degradation of systems trained using the data. To alleviate this problem, we propose a novel method for detecting errors in the existing POS tagged corpus using the classifier of XGBoost and cross-validation as evaluation techniques. We first train a classifier of a POS tagger using the POS-tagged corpus with some errors and then detect errors from the POS-tagged corpus using cross-validation, but the classifier cannot detect errors because there is no training data for detecting POS tagged errors. We thus detect errors by comparing the outputs (probabilities of POS) of the classifier, adjusting hyperparameters. The hyperparameters is estimated by a small scale error-tagged corpus, in which text is sampled from a POS-tagged corpus and which is marked up POS errors by experts. In this paper, we use recall and precision as evaluation metrics which are widely used in information retrieval. We have shown that the proposed method is valid by comparing two distributions of the sample (the error-tagged corpus) and the population (the POS-tagged corpus) because all detected errors cannot be checked. In the near future, we will apply the proposed method to a dependency tree-tagged corpus and a semantic role tagged corpus.

• Journal of the Institute of Convergence Signal Processing
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• v.4 no.2
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• pp.31-39
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• 2003

The MPEG-2 source coding algorithm is very sensitive to transmission errors due to using of variable-length coding. When the compressed data are transmitted, transmission errors are generated and error correction scheme is not able to be corrected well them. In the decoder error concealment (EC) techniques must be used to conceal errors and it is able to minimize degradation of video quality. The proposed algorithm is method to conceal successive macroblock errors of I-frame and utilize temporal information of B-frame and spatial information of P-frame In the previous GOP which is temporally the nearest location to I-frame. This method can improve motion distortion and blurring by temporal and spatial errors which cause at existing error concealment techniques. In network where the violent transmission errors occur, we can conceal more efficiently severe slice errors. This algorithm is Peformed in MPEG-2 video codec and Prove that we can conceal efficiently slice errors of I-frame compared with other approaches by simulations.

• Journal of Advanced Navigation Technology
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• v.18 no.5
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• pp.421-428
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• 2014

GPS satellite positions can be obtained from the navigation message transmitted from the GPS satellite. In this paper, the accuracy of broadcast orbit and clock are analyzed by comparing with the NGA precise ephemeris. For analyzing global and local orbit errors in 2004 to 2013, GPS satellite visibilities are calculated in Korea. Local RMS of 3D orbit error and SISRE are 4 cm and 3 cm less than global RMS of 3D orbit errors and SISRE. Orbit and clock errors are calculated for each GPS satellite Block for 10 years. SISRE of Block IIA satellites are 2.8 times greater than Block IIF satellites. The correlation between orbit errors and shadow condition is analyzed. The orbit errors in shadow is 2.1% higher than that in sunlight. Correlation analysis between the orbit errors and solar/geomagnetic index shows that orbit errors has a high correlation with from 2004 to 2008. However, the correlation became low since 2009.

• Journal of Korean Society of Transportation
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• v.34 no.5
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• pp.476-488
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• 2016

This study reviewed factors and causes that affect on reliability and accuracy of transportation demand forecasting. In general, the causes of forecasting errors come from variety and irregularity of trip behaviors, data limitation, data aggregation and model simplification. Theoretical understanding about the inevitable errors will be helpful for reasonable decision making for practical transportation policies. The study especially focused on traffic assignment with the KTDB data, and described the factors and causes of errors by classifying six categories such as (1) errors in input data, (2) errors due to spacial aggregation and representation method of network, (3) errors from representing values for variations of traffic patterns, (4) errors from simplification of traffic flow model, and (5) errors from aggregation of route choice behavior.

• The Korean Journal of Pain
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• v.23 no.1
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• pp.35-41
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• 2010

Background: Statistical analysis is essential in regard to obtaining objective reliability for medical research. However, medical researchers do not have enough statistical knowledge to properly analyze their study data. To help understand and potentially alleviate this problem, we have analyzed the statistical methods and errors of articles published in the Korean Journal of Pain (KJP), with the intention to improve the statistical quality of the journal. Methods: All the articles, except case reports and editorials, published from 2004 to 2008 in the KJP were reviewed. The types of applied statistical methods and errors in the articles were evaluated. Results: One hundred and thirty-nine original articles were reviewed. Inferential statistics and descriptive statistics were used in 119 papers and 20 papers, respectively. Only 20.9% of the papers were free from statistical errors. The most commonly adopted statistical method was the t-test (21.0%) followed by the chi-square test (15.9%). Errors of omission were encountered 101 times in 70 papers. Among the errors of omission, "no statistics used even though statistical methods were required" was the most common (40.6%). The errors of commission were encountered 165 times in 86 papers, among which "parametric inference for nonparametric data" was the most common (33.9%). Conclusions: We found various types of statistical errors in the articles published in the KJP. This suggests that meticulous attention should be given not only in the applying statistical procedures but also in the reviewing process to improve the value of the article.

• Journal of the Korean Chemical Society
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• v.54 no.6
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• pp.781-786
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• 2010

The purpose of this study was to investigate errors on written tests of science, matters, in middle school 7th grade. Errors were defined something you have done which is considered to be incorrect or wrong, or which should not have been done. We found and classified errors, and then examined the frequency of types of errors on the written tests. A total of 167 test items from 10 middle schools were analyzed for this study. Errors on the written tests were classified into 5 types: insufficient information; unnecessary information; inaccurate information; information against curriculum; and unclear information. A total of 81 errors were counted out of 167 test items. The results of this study are expected to help teachers develop written test items to convey definite meanings by text and would be used as basic information for improving written test item standards.

• Journal of the Ergonomics Society of Korea
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• v.27 no.1
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• pp.37-43
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• 2008

A lot of models have been developed for prevention of human errors. Nevertheless most of them failed to attract attention of industry which has been looking for an integrative model that can show practical countermeasures as well as causal factors of human errors. This research aimed to develop a comprehensive model that can mainly be applied to industrial fields. Therefore, in the model, it was tried to explain sequences of an operator's information process that might cause human errors on one hand, and life cycle stages of facilities involved when human errors occur on the other hand. This model was validated by using a typical accident case. With the comprehensive model presented in this research, one could follow up the sequence of human errors caused by operators, and errors made at the design stage which might cause accidents could be tracked. As a consequence, it is expected that much attention would be paid to preventing human errors in industrial fields since safety personnel can easily find out cause of human errors throughout life cycle stages of man-machine facilities if utilizing the suggested model.