• Title/Summary/Keyword: Influential observation

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A Method of Choosing a Value of the Bending Constant in Huber's M-Estimation Function

  • Park, Ro-Jin
    • Journal of the Korean Data and Information Science Society
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    • v.11 no.2
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    • pp.181-188
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    • 2000
  • The shape of an M-estimation function is generally determined in the sense of either/both maximizing efficiency of an M-estimator at the model or/and bounding the influence function of an M-estimator. We propose an empirical method of choosing a value of the bending constant in Huber's ${\psi}-function$, which is the most widely used M-estimation function when estimating the location parameter.

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Detecting the Influential Observation Using Intrinsic Bayes Factors

  • Chung, Younshik
    • Journal of the Korean Statistical Society
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    • v.29 no.1
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    • pp.81-94
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    • 2000
  • For the balanced variance component model, sometimes intraclass correlation coefficient is of interest. If there is little information about the parameter, then the reference prior(Berger and Bernardo, 1992) is widely used. Pettit nd Young(1990) considered a measrue of the effect of a single observation on a logarithmic Bayes factor. However, under such a reference prior, the Bayes factor depends on the ratio of unspecified constants. In order to discard this problem, influence diagnostic measures using the intrinsic Bayes factor(Berger and Pericchi, 1996) is presented. Finally, one simulated dataset is provided which illustrates the methodology with appropriate simulation based computational formulas. In order to overcome the difficult Bayesian computation, MCMC methods, such as Gibbs sampler(Gelfand and Smith, 1990) and Metropolis algorithm, are empolyed.

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Deletion diagnostics in fitting a given regression model to a new observation

  • Kim, Myung Geun
    • Communications for Statistical Applications and Methods
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    • v.23 no.3
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    • pp.231-239
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    • 2016
  • A graphical diagnostic method based on multiple case deletions in a regression context is introduced by using the sampling distribution of the difference between two least squares estimators with and without multiple cases. Principal components analysis plays a key role in deriving this diagnostic method. Multiple case deletions of test statistic are also considered when a new observation is fitted to a given regression model. The result is useful for detecting influential observations in econometric data analysis, for example in checking whether the consumption pattern at a later time is the same as the one found before or not, as well as for investigating the influence of cases in the usual regression model. An illustrative example is given.

A Study on the Formative Process of Genre and Storytelling in Observation Entertainment Programs - Focusing on the Role of Observer (관찰 예능의 장르화 과정과 스토리텔링 연구 -관찰자의 역할을 중심으로)

  • Lee, Hyun-Joong
    • Journal of Popular Narrative
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    • v.25 no.2
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    • pp.217-245
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    • 2019
  • Recently, the interest among Korean broadcasters in the 'observation entertainment' genre has intensified. This study aims to analyze the genre and storytelling of observation entertainment programming from a narratological perspective. The origin of the Korean observation entertainment program began with the 'reality-variety show'. There was a 'real-life' debate in these reality-variety shows, and as an alternative, the observation entertainment program appeared. Documentary filming, omnibus composition, and spatialization of 'everyday' life have led to the recognition of observation entertainment as a single genre. In particular, 'observers' have become a key factor in the observation entertainment program. The subject of the program is determined by who the observer is. The variability of the program format is the same. The observer looks at the observation target on behalf of the viewer. At the same time, he or she serves as a narrator of the program. The observer functions as the most influential factor in the storytelling of the observation entertainment program. In the observation entertainment program, 'observation' is only a form. It is the observer who creates a narrative within this same format to make the difference between each program. Also, voyeurism has been considered a problem in reality shows such as observation entertainment programs. However, the form communicated by observers is not a direct peek, so much of the problem of voyeurism is mitigated. Such observation entertainment programs analyzed through observers are meaningful in that they make people understand the cultural meaning of "reality" in TV and the storytelling of contemporary Korean TV entertainment.

A Study on the High School Student's Aggressive Behavior in School (學校에서의 高學生의 攻擊行動에 관한 硏究)

  • Kim, Gab-Sook
    • Journal of Families and Better Life
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    • v.9 no.1 s.17
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    • pp.13-26
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    • 1991
  • The purpose of the study is to examine the realities of the high school students's aggressive behavior, and to analyze factors causing aggressive behavior. Subjects were 418 Humanity High School students of 2nd grades in pusan. Analysis methods were used to frequency, percentage, t-test, one way ANOVA, Pearson's correlation, and multiple regression of SPSS program. The results are as follows ; 1) Male students are more aggressive than female students. 2) The more verbal aggression is the more physical aggression. 3) Students with the experience of parent-child violence are more aggressive. 4) Students with observation of parents's violence are more aggressive. 5) Family's social economic status is not related to the aggressive behavior. 6) Male students not admitted by teacher are more aggressive in verbal and physical behavior. 7) Female students not admitted by friend are more aggressive in verbal and physical behavior. 8) Students with deliquent friends are more aggressive in verbal and physical behavior. 9) Students with Academic anxiety are more aggressive in verbal behavior. 10) the variables influential to verbal aggressive behavior are sex, a delinquent friends and academic anaxiety. These factors explain 23.5% of the total variance of verbal aggressive behavior variables. The variables influential to physical aggressive behavior are a delinquent friends, sex, experience of parent-child violence and teacher's denial attitude. These factors explain 29.6% of the total variance for physical aggressive behavior variables.

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Effect of outliers on the variable selection by the regularized regression

  • Jeong, Junho;Kim, Choongrak
    • Communications for Statistical Applications and Methods
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    • v.25 no.2
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    • pp.235-243
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    • 2018
  • Many studies exist on the influence of one or few observations on estimators in a variety of statistical models under the "large n, small p" setup; however, diagnostic issues in the regression models have been rarely studied in a high dimensional setup. In the high dimensional data, the influence of observations is more serious because the sample size n is significantly less than the number variables p. Here, we investigate the influence of observations on the least absolute shrinkage and selection operator (LASSO) estimates, suggested by Tibshirani (Journal of the Royal Statistical Society, Series B, 73, 273-282, 1996), and the influence of observations on selected variables by the LASSO in the high dimensional setup. We also derived an analytic expression for the influence of the k observation on LASSO estimates in simple linear regression. Numerical studies based on artificial data and real data are done for illustration. Numerical results showed that the influence of observations on the LASSO estimates and the selected variables by the LASSO in the high dimensional setup is more severe than that in the usual "large n, small p" setup.

Parametric study on multichannel analysis of surface waves-based nondestructive debonding detection for steel-concrete composite structures

  • Hongbing Chen;Shiyu Gan;Yuanyuan Li;Jiajin Zeng;Xin Nie
    • Steel and Composite Structures
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    • v.50 no.1
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    • pp.89-105
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    • 2024
  • Multichannel analysis of surface waves (MASW) method has exhibited broad application prospects in the nondestructive detection of interfacial debonding in steel-concrete composite structures (SCCS). However, due to the structural diversity of SCCS and the high stealthiness of interfacial debonding defects, the feasibility of MASW method needs to be investigated in depth. In this study, synthetic parametric study on MASW nondestructive debonding detection for SCCSs is performed. The aim is to quantitatively analyze influential factors with respect to structural composition of SCCS and MASW measurement mode. First, stress wave composition and propagation process in SCCS are studied utilizing 2D numerical simulation. For structural composition in SCCS, the thickness variation of steel plate, concrete core, and debonding defects are discussed. To determine the most appropriate sensor arrangement for MASW measurement, the effects of spacing and number of observation points, along with distances between excitation points, nearest boundary, as well as the first observation point, are analyzed individually. The influence of signal type and frequency of transient excitation on dispersion figures from forwarding analysis is studied to determine the most suitable excitation signal. The findings from this study can provide important theoretical guidance for MASW-based interfacial debonding detection for SCCS. Furthermore, they can be instrumental in optimizing both the sensor layout design and signal choice for experimental validation.

Effects of Rice Straw Particle Size on Chewing Activity, Feed Intake, Rumen Fermentation and Digestion in Goats

  • Zhao, X.G.;Wang, M.;Tan, Z.L.;Tang, S.X.;Sun, Z.H.;Zhou, C.S.;Han, X.F.
    • Asian-Australasian Journal of Animal Sciences
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    • v.22 no.9
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    • pp.1256-1266
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    • 2009
  • Effects of particle size and physical effective fibre (peNDF) of rice straw in diets on chewing activities, feed intake, flow, site and extent of digestion and rumen fermentation in goats were investigated. A 4${\times}$4 Latin square design was employed using 4 mature Liuyang black goats fitted with permanent ruminal, duodenal, and terminal ileal fistulae. During each of the 4 periods, goats were offered 1 of 4 diets that were similar in nutritional content but varied in particle sizes and peNDF through alteration of the theoretical cut length of rice straw (10, 20, 40, and 80 mm, respectively). Dietary peNDF contents were determined using a sieve for particle separation above 8 mm, and were 17.4, 20.9, 22.5 and 25.4%, respectively. Results showed that increasing the particle size and peNDF significantly (p<0.05) increased the time spent on rumination and chewing activities, duodenal starch digestibility and ruminal pH, and decreased ruminal starch digestibility and $NH_{3}$-N concentration. Intake and total tract digestibility of nutrients (i.e. dry matter, organic matter, and starch) and ruminal fermentation were not affected by the dietary particle size and peNDF. Increased particle size and peNDF did not affect ruminal fibre digestibility, but had a great impact on the intestinal and total tract fibre digestibility. The study suggested that rice straw particle size or dietary peNDF was the important influential factor for chewing activity, intestinal fibre and starch digestibility, and ruminal pH, but had minimal impact on feed intake, duodenal and ileal flow, ruminal and total tract digestibility, and ruminal fermentation.

Inflence of nearby structures in braced excavation (버팀굴착에서 인접 구조물의 영향평가)

  • 유일형;김형탁
    • Proceedings of the Korean Geotechical Society Conference
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    • 1994.09a
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    • pp.139-148
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    • 1994
  • Rapid industrialization and urbanization caused by the high economic growth of the country requires optimization of land usage as well as the expansion of underground space. Therefore the construction of large and deep basements is inevitable in built up areas where the braced excavation for earth retaining structures may create many problems such as settlement and damages of nearby buildings and underground utilities. In this work, some of major influential factors concerning the stability of braced excavation are investigated and the results are compared with the field observation results. The ground water table, applied strut forces, horezontal wall displacement, infilling materials in the rock joints were found to be the most critical factors influencing the stability of braced walls constructed in the layered ground. Magnituide and type of the wall deformation was closely related to the pattern of the surface settlement. The stability of braced walls are described in terms of strut forces.

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OBSERVATION ON PATCH TEST USING A FEW DENTAL MEDICAMENTS BASED ON NURSING ASPECT (치과용 약제 접촉이 인체피부조직에 미치는 영향에 관한 간호학적 고찰)

  • Han, Song-Ja
    • The Journal of the Korean dental association
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    • v.16 no.12 s.115
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    • pp.941-944
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    • 1978
  • The author studied skin reactions and their incidences among 100 dental students and dental nurses to 2% Lidocaine HC1, 3% H₂O₂, Euginol, 5% Sodium Hypochlorite, Dycal and Adhesive plaster by means of Patch test. Following are the results of the study. 1. Eighty six cases out of 100 revealed slight response to 1 or 2 allergens. 2. 2% Lidocaine HC1 showed 1 case, 3% H₂O₂cases, Euginol 2 cases, 5% Sodium Hypochlorite 74 cases, Dycal 1 case Adhesive plaster 8 cases. 3. 5% Sodium Hypochlorite was the most influential to skin. 32 cases showed grade 1+, 20 cases showed grade 2++, 16 cases showed grade 3+++, 6 cases showed grade 4++++,

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