• Journal of the Korean Data and Information Science Society
• /
• 제28권3호
• /
• pp.515-524
• /
• 2017

이 연구에서는 분류를 위한 RF (random forest)의 크기 결정에 유용한 승리표차 MV (margin of victory)에 기반한 불일치 측도를 제안하고자 한다. 여기서 MV는 현재의 RF에서 1등과 2등을 차지하는 집단이 무한 RF에서 차지하는 승리표차이다. 구체적으로 -MV가 양수이면 현재와 무한 RF 사이에 1등과 2등인 집단에서 불일치가 생긴다는 점에 착안하여, max(-MV, 0)을 하나의 불일치 측도로 제안한다. 이 불일치 측도에 근거하여 RF의 크기 결정에 적절한 진단통계량을 제안하며, 또한 이 통계량의 이론적인 점근분포를 유도한다. 마지막으로 이 통계량을 최근에 제안된 진단통계량들과 소표본 하에서 성능을 비교하는 모의실험을 실행한다.

• Journal of the Korean Statistical Society
• /
• 제21권1호
• /
• pp.59-69
• /
• 1992

A measure is proposed to represent the degree of residuals from the symmetry model for square contingency tables with nominal categories. The measure is derivedby modifying the sum of squared singular values for a skew symmetric matrix of the residuals from the symmetry model. The proposed measure would be useful for comparing the degree of residuals from the symmetry model in several tables.

• 한국환경교육학회지:환경교육
• /
• 제15권2호
• /
• pp.61-75
• /
• 2002

This study was intended to develop a new measure for environmental education research, named ‘Subjectively Responsible Environmental Behavior(SREB), in order to overcome a few of limitations embedded in the previous measures. The results of the study suggested that there were several barriers for learners to take environment-friendly actions, willingness to act was always stronger than self-reported act and the degree of discrepancy between willingness to act and self-reported act is correlated with perceived effectiveness, perceived difficulty, and expected guilty. In terms of participation, this study defined one of major missions of environmental educators is to help learners to identify and overcome such barriers. A new measure that this study has proposed can be better utilized to evaluate effectiveness of environmental education curriculum or programs and find information necessary for modifying the programs than to assess learners' achievement. Some limitations of the proposed measure were also discussed.

• 무역학회지
• /
• 제47권2호
• /
• pp.31-46
• /
• 2022

The purpose of this study is to measure the degree of discrepancies in the bilateral trade data between South Korea and its five major trade partners and to identify the key factors causing the discrepancies. By analyzing statistics based on the CIF/FOB ratio estimation and taking into consideration the trade flow via Hong Kong, the study finds that the discrepancies in South Korea's trade data with the US, Vietnam, and Japan are insignificant. In case of Hong Kong, however, the value of South Korea's import from Hong Kong is extensively inconsistent with Hong Kong's export to South Korea(i.e. the mirror data) while the value of South Korea's export to Hong Kong generally corresponds to its mirror data. Such discrepancies are caused by differences in recording re-exports, which are often found in the trade flow via entrepôt economics including Hong Kong. Meanwhile, discrepancies in reported bilateral trade flows between South Korea and People's Republic of China(PRC) remain relatively marginal. The discrepancy of statistics between South Korea as the exporter and PRC as the importer is mainly caused by the trade flow via Hong Kong. On the other hand, the discrepancy of statistics between South Korea as the importer and PRC as the exporter is assumably due to the differences in attribution of trade partners.

• Journal of the Korean Statistical Society
• /
• 제27권3호
• /
• pp.289-303
• /
• 1998

For square contingency tables with ordered categories, Tomizawa (1995) considered two kinds of measures to represent the degree of departure from global symmetry, which means that the probability that an observation will fall in one of cells in the upper-right triangle of square table is equal to the probability that the observation falls in one of cells in the lower-left triangle of it. This paper proposes a generalization of those measures. The proposed measure is expressed by using Cressie and Read's (1984) power divergence or Patil and Taillie's (1982) diversity index. Special cases of the proposed measure include TomiBawa's measures. The proposed measure would be useful for comparing the degree of departure from global symmetry in several tables.

• Journal of the Korean Statistical Society
• /
• 제21권2호
• /
• pp.93-110
• /
• 1992

A model selection approach is used to find out whether the mean and the variance of a unique sample are different from the pre-specified values. Normal distribution is selected as an approximating model. Kullback-Leibler discrepancy comes out as a natural measure of discrepancy between the operating model and the approximating model. Several estimates of selection criterion are computed including AIC, TIC, and a coupleof bootstrap estimator of the selection criterion are considered according to the way of resampling. It is shown that a closed form expression is available for the parametric bootstrap estimated cirterion. A Monte Carlo study is provided to give a formal comparison when the operating family itself is normally distributed.

• The Journal of Advanced Prosthodontics
• /
• 제10권5호
• /
• pp.347-353
• /
• 2018

PURPOSE. The purpose of this study was to evaluate the marginal discrepancy of heat-pressed ceramic veneers manufactured using a CAD/CAM system. MATERIALS AND METHODS. The ceramic veneers for the abutment of a maxillary left central incisor were designed using a CAD/CAM software program. Ten veneers using a microstereolithography apparatus (AM group), ten veneers using a five-axis milling machine (SM group), and ten veneers using a traditional free-hand wax technique (TW group) were prepared according to the respective manufacturing method. The ceramic veneers were also fabricated using a heat-press technique, and a silicone replica was used to measure their marginal discrepancy. The marginal discrepancies were measured using a digital microscope (${\times}160$ magnification). The data were analyzed using a nonparametric Kruskal-Wallis H test. Finally, post-hoc comparisons were conducted using Bonferroni-corrected Mann-Whitney U tests (${\alpha}=.05$). RESULTS. The $mean{\pm}SD$ of the total marginal discrepancy was $99.68{\pm}28.01{\mu}m$ for the AM group, $76.60{\pm}28.76{\mu}m$ for the SM group, and $83.08{\pm}39.74{\mu}m$ for the TW group. There were significant differences in the total marginal discrepancies of the ceramic veneers (P<.05). CONCLUSION. The SM group showed a better fit than the AM and TW groups. However, all values were within the clinical tolerance. Therefore, CAD/CAM manufacturing methods can replace the traditional free-hand wax technique.

• PNF and Movement
• /
• 제17권3호
• /
• pp.391-399
• /
• 2019

Purpose: This study investigated the three-dimensional moment values of the hip joint for subjects with artificial leg length alterations and subjects with unaltered leg lengths. Methods: Forty-two healthy adults (8 men, 34 women) participated in this study. The selected subjects were able to walk normally, had less than a 1 cm leg length discrepancy, and were instructed to wear shoes that fit their feet. The study participants performed 8 dynamic gait trails to measure the hip joint moment using a three-dimensional motion analysis system. Kinetic and dynamic three-dimensional gait analysis data were collected from infrared cameras, and a force plate was used to standardize the weight of each subject. Results: There were significant correlations between the differences in the leg length discrepancy during right extension, right flexion, right internal rotation, and left extension in hip joint moments (p<0.05). There were significant correlations between the differences in shoe conditions during left extension, right flexion, right extension, and right internal rotation in the hip moments (p<0.05). Conclusion: This study suggests that a leg length discrepancy can affect hip joint moment, which may further exacerbate musculoskeletal disorders, such as osteoarthritis in lower extremity joints. Therefore, further studies should be conducted to verify the impact of clinical interventions on differences in hip joint moment values to correct leg length discrepancies and prevent osteoarthritis in lower extremity joints.

• Journal of the Korean Statistical Society
• /
• 제31권2호
• /
• pp.237-250
• /
• 2002

Motivated by Cook's (1986) assessment of local influence by investigating the curvature of a surface associated with the overall discrepancy measure, this paper extends this idea to the linear regression model with AR(p) disturbances. Diagnostic for the linear regression models with AR(p) disturbances are discussed when simultaneous perturbations of the response vector are allowed. For the derived criterion, numerical studies demonstrate routine application of this work.

• 대한치과교정학회지
• /
• 제33권1호
• /
• pp.41-49
• /
• 2003

골격성 III급 부정교합자는 부적절한 악골 위치에서 기능 교합을 유지하기 위해 치아의 경사도와 수직적 위치가 변화하게 된다. 이러한 치성보상은 전치부 및 구치부 전반에 걸쳐 일어나며, 현재 보편적으로 시행되고 있는 악교정수술을 위한 술전교정시 이를 제거하여 각 골격 구조내에서 치아들이 적절히 위치되도록 하여야 한다. 전치부 치성보상에 관한 측모 두부방사선 사진을 이용한 연구는 많이 시행되어졌으나, 구치부 경사도에 관한 연구는 미미 한 실정이다. 이에 본 연구는 성인 골격성 III급 부정교합자의 전후방적, 수직적 악골 부조화에 따른 폭경 부조화 및 구치 경사도 변화를 알아보기 위해 진단 모형상에서 상하악 견치, 제1소구치, 제1대구치 부위의 기저골 폭경을 측정하여 상악에 대한 하악의 비율을 구하였으며, 모형 을 삭제하여 좌우 구치간 경사도를 측정하였다. 악골 부조화 심화에 따른 기저골 폭경 비율과 제1대구치 협설 경사도 변화의 상관관계를 조사하여 다음과 같은 결론을 얻었다. 1. 골격성 III급 부정교합자의 악골의 전후방적 부조화가 심화될수록 상하악 구치간 각도합이 증가하여 치성보상이 많이 일어났으며, 특히 하악 구치가 설측 경사되는 치성보상을 보였다(p<0.001). 2. 골격성 III급 부정교합자의 악골의 수직적 부조화 및 폭경 부조화와 구치부 치성보상 간에는 유의할만한 상관성이 없었다. 3. 골격성 III급 부정교합자의 전후방적, 수직적 부조화의 심화와 기저골 폭경 부조화는 유의할만한 상관성이 없었다.