• Educational Technology International
• /
• 제15권1호
• /
• pp.1-26
• /
• 2014

The purpose of this study was to develop design principles of both animated pedagogical agents as 'credible' persuasive message source and persuasive fear arousing instructional messages in order to help enhance attitude changes toward a certain issue. Based on the previous pedagogical agent research, this study drew the design principles providing ways to manipulate agent credibility level and fear arousing level of message. Consequently, it specified how to make pedagogical agents perceived less or more credible by learners by manipulating a variety of agent features. For fear arousing message, this study showed how fear arousing messages would be structured into one of three levels: non-threatening, moderately threatening, and strongly threatening. Two different agent conditions and three message conditions were actually developed and experimentally tested with the participants of 40 undergraduate students. The results showed that the agent design principles specified from the previous research worked well enough to make a distinction between the more credible agent and the less credible agent. The overall results of this study may indicate that the design strategies for fear arousing message are retained on the premise of some future refinements.

• Communications for Statistical Applications and Methods
• /
• 제14권1호
• /
• pp.11-21
• /
• 2007

In this paper, we consider a decision-theoretic oriented, objective Bayesian inference for the difference between two normal means with unknown com-mon variance. We derive the Bayesian reference criterion as well as the intrinsic estimator and the credible region which correspond to the intrinsic discrepancy loss and the reference prior. We illustrate our results using real data analysis as well as simulation study.

• Journal of the Korean Statistical Society
• /
• 제23권2호
• /
• pp.445-461
• /
• 1994

This paper deals with the problem of obtaining some Bayes estimators and Bayesian credible regions of a reliability function for the Rayleigh distribution. Using several priors for a reliability function some Bayes estimators and Bayes credible sets are proposed and studied under squared error loss and Harris loss. Also the performances and behaviors of the proposed Bayes estimators are examined via Monte Carlo simulations and some numericla examples are given.

• Journal of the Korean Data and Information Science Society
• /
• 제17권4호
• /
• pp.1365-1374
• /
• 2006

In this paper, we consider a decision-theoretic oriented, objective Bayesian inference for the difference between two normal means with known variances. We derive the Bayesian reference criterion as well as the intrinsic estimator and the credible region which correspond to the intrinsic discrepancy loss and the reference prior. We show the similarity between derived two-sample results and the results for the one-sample case in Bernardo(1999).

• Journal of the Korean Data and Information Science Society
• /
• 제18권1호
• /
• pp.219-228
• /
• 2007

In this paper, we consider a decision-theoretic oriented, objective Bayesian inference for the ratio of two normal variances. Specifically we derive the Bayesian reference criterion as well as the intrinsic estimator and the credible region which correspond to the intrinsic discrepancy loss and the reference prior. We illustrate our results using real data analysis and simulation study.

• Journal of the Korean Statistical Society
• /
• 제31권1호
• /
• pp.17-31
• /
• 2002

This paper considers noninformative priors for the power law process under failure truncation. Jeffreys'priors as well as reference priors are found when one or both parameters are of interest. These priors are compared in the light of how accurately the coverage probabilities of Bayesian credible intervals match the corresponding frequentist coverage probabilities. It is found that the reference priors have a definite edge over Jeffreys'prior in this respect.

• Journal of the Korean Data and Information Science Society
• /
• 제15권4호
• /
• pp.743-752
• /
• 2004

In this paper, we develop the Bayesian model selection procedure using the reference prior for comparing two nested model such as the independent and intraclass models using the distance or divergence between the two as the basis of comparison. A suitable criterion for this is the power divergence measure as introduced by Cressie and Read(1984). Such a measure includes the Kullback -Liebler divergence measures and the Hellinger divergence measure as special cases. For this problem, the power divergence measure turns out to be a function solely of $\rho$, the intraclass correlation coefficient. Also, this function is convex, and the minimum is attained at $\rho=0$. We use reference prior for $\rho$. Due to the duality between hypothesis tests and set estimation, the hypothesis testing problem can also be solved by solving a corresponding set estimation problem. The present paper develops Bayesian method based on the Kullback-Liebler and Hellinger divergence measures, rejecting $H_0:\rho=0$ when the specified divergence measure exceeds some number d. This number d is so chosen that the resulting credible interval for the divergence measure has specified coverage probability $1-{\alpha}$. The length of such an interval is compared with the equal two-tailed credible interval and the HPD credible interval for $\rho$ with the same coverage probability which can also be inverted into acceptance regions of $H_0:\rho=0$. Example is considered where the HPD interval based on the one-at- a-time reference prior turns out to be the shortest credible interval having the same coverage probability.

• 정보관리학회지
• /
• 제27권2호
• /
• pp.21-35
• /
• 2010

야후 앤서(Yahoo! Answers)와 네이버 지식인과 같은 지식 검색 커뮤니티가 활성화되면서 전문가가 아닌 일반인이 제공하는 정보에 대한 신뢰성이 끊임없이 제기되어 왔지만 일반인 답변자들의 신뢰성 있는 정보 제공 노력에 대한 연구는 미흡한 실정이다. 이에 본 연구는 야후 앤서에서 활동하는 44명의 일반인 답변자들과의 이메일, 채팅, 전화 인터뷰를 통해 그들이 이용하는 정보원, 신뢰성 있는 정보 제공을 위한 전략, 그리고 자칭 전문성(self-claimed expertise)에 대한 인식을 알아보았다. 본 연구의 결과는, 일반인을 효과적인 정보제공자로 교육시키는 이용자 교육 측면에서 활용될 수 있다.

• Communications for Statistical Applications and Methods
• /
• 제27권1호
• /
• pp.47-64
• /
• 2020

In this paper, we derive some estimators of the scale parameter of the exponentiated half-logistic distribution based on the multiply Type-I hybrid censoring scheme. We assume that the shape parameter λ is known. We obtain the maximum likelihood estimator of the scale parameter σ. The scale parameter is estimated by approximating the given likelihood function using two different Taylor series expansions since the likelihood equation is not explicitly solved. We also obtain Bayes estimators using prior distribution. To obtain the Bayes estimators, we use the squared error loss function and general entropy loss function (shape parameter q = -0.5, 1.0). We also derive interval estimation such as the asymptotic confidence interval, the credible interval, and the highest posterior density interval. Finally, we compare the proposed estimators in the sense of the mean squared error through Monte Carlo simulation. The average length of 95% intervals and the corresponding coverage probability are also obtained.

• 한국건설관리학회:학술대회논문집
• /
• 한국건설관리학회 2002년도 학술대회지
• /
• pp.478-481
• /
• 2002

현재 국내 건설프로젝트에 EVMS가 도입되어 비용과 공정을 효과적으로 통합하여 관리하고 있으나 EVMS는 선진 외국의 건설환경에 적합한 방법으로서 이 EVMS를 국내에 적용하는 데에는 다소 어려운 점이 발견되고 있다. 본 논문에서는 EVMS에서 최종공사비(EAC)를 예측하는데 사용되고 있는 지수중의 하나인 합성지수(CI)의 가중치 n, m에 대한 통계적 분석을 통하여 신뢰구간상에 나타나는 합성지수(CI)를 검정하여 최종공사비(EAC)를 예측하는데 효과적으로 사용하고자 한다.