• Title/Summary/Keyword: Statistical Difference

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Model Checking for Time-Series Count Data

  • Lee, Sung-Im
    • Communications for Statistical Applications and Methods
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    • v.12 no.2
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    • pp.359-364
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    • 2005
  • This paper considers a specification test of conditional Poisson regression model for time series count data. Although conditional models for count data have received attention and proposed in several ways, few studies focused on checking its adequacy. Motivated by the test of martingale difference assumption, a specification test via Ljung-Box statistic is proposed in the conditional model of the time series count data. In order to illustrate the performance of Ljung- Box test, simulation results will be provided.

Sequential Estimation with $\beta$-Protection of the Difference of Two Normal Means When an Imprecision Function Is Variable

  • Kim, Sung-Lai;Kim, Sung-Kyun
    • Journal of the Korean Statistical Society
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    • v.31 no.3
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    • pp.379-389
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    • 2002
  • For two normal distribution with unknown means and unknown variances, a sequential procedure for estimating the difference of two normal means which satisfies both the coverage probability condition and the $\beta$-protection is proposed under some smoothness of variable imprecision function, and the asymptotic normality of the proposed stopping time after some centering and scaling is given.

Confidence Intervals for the Difference of Binomial Proportions in Two Doubly Sampled Data

  • Lee, Seung-Chun
    • Communications for Statistical Applications and Methods
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    • v.17 no.3
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    • pp.309-318
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    • 2010
  • The construction of asymptotic confidence intervals is considered for the difference of binomial proportions in two doubly sampled data subject to false-positive error. The coverage behaviors of several likelihood based confidence intervals and a Bayesian confidence interval are examined. It is shown that a hierarchical Bayesian approach gives a confidence interval with good frequentist properties. Confidence interval based on the Rao score is also shown to have good performance in terms of coverage probability. However, the Wald confidence interval covers true value less often than nominal level.

Identification of indirect effects in the two-condition within-subject mediation model and its implementation using SEM

  • Eujin Park;Changsoon Park
    • Communications for Statistical Applications and Methods
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    • v.30 no.6
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    • pp.631-652
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    • 2023
  • In the two-condition within-subject mediation design, pairs of variables such as mediator and outcome are observed under two treatment conditions. The main objective of the design is to investigate the indirect effects of the condition difference (sum) on the outcome difference (sum) through the mediator difference (sum) for comparison of two treatment conditions. The natural condition variables mean the original variables, while the rotated condition variables mean the difference and the sum of two natural variables. The outcome difference (sum) is expressed as a linear model regressed on two natural (rotated) mediators as a parallel two-mediator design in two condition approaches: the natural condition approach uses regressors as the natural condition variables, while the rotated condition approach uses regressors as the rotated condition variables. In each condition approach, the total indirect effect on the outcome difference (sum) can be expressed as the sum of two individual indirect effects: within- and cross-condition indirect effects. The total indirect effects on the outcome difference (sum) for both condition approaches are the same. The invariance of the total indirect effect makes it possible to analyze the nature of two pairs of individual indirect effects induced from the natural conditions and the rotated conditions. The two-condition within-subject design is extended to the addition of a between-subject moderator. Probing of the conditional indirect effects given the moderator values is implemented by plotting the bootstrap confidence intervals of indirect effects against the moderator values. The expected indirect effect with respect to the moderator is derived to provide the overall effect of moderator on the indirect effect. The model coefficients are estimated by the structural equation modeling approach and their statistical significance is tested using the bias-corrected bootstrap confidence intervals. All procedures are evaluated using function lavaan() of package {lavaan} in R.

A study on the theory for Integrating of Statistical Process Control and Process Adjustmen (통계적 공정관리와 공정조절의 통합을 위한 이론에 대한연구)

  • Jung, Hae-Woon
    • Proceedings of the Safety Management and Science Conference
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    • 2005.11a
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    • pp.493-504
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    • 2005
  • Statistical Process Control and Process Adjustment theory is gaining recognition in the process industries where the process frequently experiences a shift mean. This paper aims to study, the theory difference between Statistical Process Control and Process Adjustment in simple terms and presents a case study that demonstrates successful integration of Statistical Process Control and Process Adjustment theory for a product in drifting industry.

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A Statistical Approach for the Determination of Location and Range of Fishing Grounds in the Coastal Vessel Fishery (통계학적 접근에 의한 연안어업의 조업어장 위치 및 범위결정 에 관한 연구)

  • Kang, Y.J.;Kim, K.S.;Yi, S.B.
    • The Journal of Fisheries Business Administration
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    • v.38 no.1 s.73
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    • pp.97-113
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    • 2007
  • This study attempts to suggest a new approach of the the determination of location and range of fishing ground in the coastal vessel fishery using the anaiysis of variance(ANOVA) and least significant difference test(LSD test) in statistics. The important result of the empirical study is that there is no significant difference in fisfishing ground based on between fishermen's argument and spot investigation. But there is stastitically significant difference in fisfishing ground based on between fishermen's argument and the official documents of fishing records for past three years. The results suggest us that there exists a possibility of misuse of tax free oil providied for subsidizing fisheries. But because of the range limitation of data, it is impossible for us to generalize the above results.

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A Robust Estimator in Multivariate Regression Using Least Quartile Difference

  • Jung Kang-Mo
    • Communications for Statistical Applications and Methods
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    • v.12 no.1
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    • pp.39-46
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    • 2005
  • We propose an equivariant and robust estimator in multivariate regression model based on the least quartile difference (LQD) estimator in univariate regression. We call this estimator as the multivariate least quartile difference (MLQD) estimator. The MLQD estimator considers correlations among response variables and it can be shown that the proposed estimator has the appropriate equivariance properties defined in multivariate regressions. The MLQD estimator has high breakdown point as does the univariate LQD estimator. We develop an algorithm for MLQD estimate. Simulations are performed to compare the efficiencies of MLQD estimate with coordinatewise LQD estimate and the multivariate least trimmed squares estimate.

Phase II Study on EANI Combined with Hydrochloride Palonosetron for Prevention of Chemotherapy-induced Nausea and Vomiting Following Highly Emetogenic Chemotherapy

  • Xiao, Yang;Liu, Jun;Liu, Yang-Chen;Huang, Xin-En;Guo, Jian-Xong;Wei, Wei
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.9
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    • pp.3951-3954
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    • 2014
  • Objective: To investigate the electronic anti-nausea instrument (EANI) combined with hydrochloride palonosetron for prevention of chemotherapy-induced nausea and vomiting following highly emetogenic chemotherapy. Methods: Patients who received highly emetogenic chemotherapy were randomly assigned to a treatment group (60 patients) treated with EANI combined with hydrochloride palonosetron, and control group (also 60 patients) given only hydrochloride palonosetron. Chemotherapy related nausea and vomiting were observed and recorded in both groups of patients from the start till the end of chemotherapy. Results: Complete control rates of vomiting in treatment and control group were 40%, and 35%, respectively, without any statistical ly significant difference (p>0.05); however the response rates are 95.0%, 78.3%, respectively, with statistical difference (p<0.05). Complete control rates of nausea in treatment and control group were 36.7%, 30%, respectively, without statistical difference (p>0.05); but the response rates are 90.0%, 76.7%, respectively, with statistical difference (p<0.05). Conclusion: EANI combined with hydrochloride palonosetron for prevention of nausea and vomiting induced by chemotherapy could be more effective than hydrochloride palonosetron alone, and can be recommended for use in prevention and treatment of chemotherapy-induced nausea and vomiting following highly emetogenic chemotherapy.

A Clinical Report on 35 Inpatients with Facial Paralysis Effects of Early Oriental Medicine Treatment on House-Brackmann Grade in Bell's Palsy (벨마비 입원환자 35례에 대한 임상보고 조기 한방치료가 벨마비에서 House-Brackmann grade에 미치는 영향을 중심으로)

  • Yang, Hyun-Ju;Joo, Hyun-A;Baek, Sang-Chul;Park, Jin-Soo;Hong, Seok-Hoon
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.24 no.3
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    • pp.108-118
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    • 2011
  • Objective : This study was designed to evaluate the influence of time from onset of Bell's palsy until commenced Oriental medicine therapy on Bell's palsy. Methods : We investigated 35 cases of patients with peripheral facial palsy who visited Wonkwang University Oriental Hospital from 10th, December 2010 to 31st August, 2011 and classified them as time from onset of Bell's palsy until commenced Oriental medicine therapy. Time from onset of Bell's palsy until commenced Oriental medicine therapy of Group A was within 3 days. Group B was from 4 days to 8 days. We evaluate the treatment effect of each group by House-Brackmann grade before treatment and 1,3 week treatment. Results : 1. There was a statistical difference in period from onset of Bell's palsy until commenced Oriental medicine therapy between Group A and Group B. 2. There was a statistical difference after 1 week treatment in Group B. 3. There was a statistical difference after 3 weeks treatment in both Group A and B.3. After 3 week treatment, there was statistical significant difference in decreased value of House-Brackmann grade between Group A and Group B. Group A showed more recovery compared with Group B. Conclusions : 1. These results suggest that early oriental medicine treatment could be more effective in recovery of Bell's palsy. 2. Further studies will be required to identify the beneficial effect of early oriental medicine treatment in bell's palsy.