• Title/Summary/Keyword: measure of discrepancy

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A measure of discrepancy based on margin of victory useful for the determination of random forest size (랜덤포레스트의 크기 결정에 유용한 승리표차에 기반한 불일치 측도)

  • Park, Cheolyong
    • Journal of the Korean Data and Information Science Society
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    • v.28 no.3
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    • pp.515-524
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    • 2017
  • In this study, a measure of discrepancy based on MV (margin of victory) has been suggested that might be useful in determining the size of random forest for classification. Here MV is a scaled difference in the votes, at infinite random forest, of two most popular classes of current random forest. More specifically, max(-MV,0) is proposed as a reasonable measure of discrepancy by noting that negative MV values mean a discrepancy in two most popular classes between the current and infinite random forests. We propose an appropriate diagnostic statistic based on this measure that might be useful for the determination of random forest size, and then we derive its asymptotic distribution. Finally, a simulation study has been conducted to compare the performances, in finite samples, between this proposed statistic and other recently proposed diagnostic statistics.

GAUSS DISCREPANCY TYPE MEASURE OF DEGREE OF RESIDUALS FROM SYMMETRY FOR SQUARE CONTINGENCY TABLES

  • Tomizawa, Sadao;Murata, Mariko
    • Journal of the Korean Statistical Society
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    • v.21 no.1
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    • pp.59-69
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    • 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.

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A New Measure in Environmental Education Research : Subjectively Responsible Environmental Behavior (SREB) (환경교육 연구의 새로운 측정치 - 주관적으로 책임있는 환경 행동)

  • 이재영;김인호
    • Hwankyungkyoyuk
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    • v.15 no.2
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    • pp.61-75
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    • 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.

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A Study on Statistics Discrepancies in the Bilateral Trade Between Korea and Its Major Partners - Focusing on PRC and Hong Kong - (한국과 주요 교역국 간 무역통계 불일치에 관한 연구 - 중국과 홍콩을 중심으로 -)

  • Seung-Kwan Shin
    • Korea Trade Review
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    • v.47 no.2
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    • pp.31-46
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    • 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.

Generalized Measure of Departure From Global Symmetry for Square Contingency Tables with Ordered Categories

  • Tomizawa, Sadao;Saitoh, Kayo
    • Journal of the Korean Statistical Society
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    • v.27 no.3
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    • pp.289-303
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    • 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.

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On the Model Selection Criteria in Normal Distributions

  • Chung, Han-Yeong;Lee, Kee-Won
    • Journal of the Korean Statistical Society
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    • v.21 no.2
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    • pp.93-110
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    • 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.

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Evaluation of marginal discrepancy of pressable ceramic veneer fabricated using CAD/CAM system: Additive and subtractive manufacturing

  • Kang, Seen-Young;Lee, Ha-Na;Kim, Ji-Hwan;Kim, Woong-Chul
    • The Journal of Advanced Prosthodontics
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    • v.10 no.5
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    • pp.347-353
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    • 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.

Effect of Artificial Leg Length Discrepancy on 3D Hip Joint Moments during Gait in Healthy Individuals (건강한 성인에서 인위적 다리길이 차이가 보행 중 3차원 엉덩관절 모멘트에 미치는 효과)

  • Jo, Min-Ji;Kim, Dong-Hyun;Han, Dong-Wook;Choi, Eun-Jin;Kim, Ye-Seul;Kim, Yong-Wook
    • PNF and Movement
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    • v.17 no.3
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    • pp.391-399
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    • 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.

Diagnostics for Regression with Finite-Order Autoregressive Disturbances

  • Lee, Young-Hoon;Jeong, Dong-Bin;Kim, Soon-Kwi
    • Journal of the Korean Statistical Society
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    • v.31 no.2
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    • pp.237-250
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    • 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.

The relationship between posterior dental compensation and skeletal discrepancy in class III malocclusion (골격성 III급 부정교합자의 악골 부조화가 구치부 치성보상에 미치는 영향)

  • Sung, Ji-Hyun;Son, Woo-Sung;Kim, Sung-Sik
    • The korean journal of orthodontics
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    • v.33 no.1 s.96
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    • pp.41-49
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    • 2003
  • This study examined the relations between degree of posterior dental compensation and skeletal discrepancy in Class III malocclusion. The pretreatment lateral cephalogras and dental casts of 87 skeletal Class III adults were selected to provide a random sampling of skeletal Class III malocclusion. Skeletal discrepancy was described with ANB angle, Wits appraisal, SN-Mn plane angle, FMA and ratios of basal arch width. Degree of posterior dental compensation was described with maxillary intermolar angle, mandibular interolar angle and sum of intermoloar angle. The relationships between skeletal discrepancy and degree of posterior dental compensation were analyzed with simple correlation analysis, stepwise multiple regression analysis. The results were as follows 1. A strong association was found between the variation in the anteroposterior measure, ANB angle and the variation of posterior dental compensation measures, sum of intermolar angle and mandibular intermolar angle in skeletal Class III malocclusion. 2. There was no statistically significant relationship between the variation in the vertical measures and the variation of posterior dental compensation measures in skeletal Class III malocclusion. 3. There was no statistically significant relationship between the variation in the anteroposterior and vortical measures and degree of basal arch width discrepancy.