• Title/Summary/Keyword: exchangeability

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Weight of Modularization using the Exchangeability of Product (교체성을 고려한 모듈화 결정요소의 중요도)

  • Mok, Hak-Soo;Jeon, Chang-Su;Han, Chang-Hyo;Song, Min-Jun
    • Transactions of the Korean Society of Automotive Engineers
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    • v.16 no.4
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    • pp.21-28
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    • 2008
  • The exchangeability of subassembly has a good relationship with the modularization of product. This relationship can be found by the analysis of the characteristics of a product. The weight for decision factors for the modularization can be determined by the exchangeability of a product or subassembly. The functions, structure, materials of subassembly are used as the decision parameters of exchangeability. Using these selected parameters, the modularization of a product, the characteristics of product structure, and the product function are analyzed. And then, the weighting factors could be calculated quantitatively using this relationship and the parameters of the exchangeability. The calculated weight can contribute to help a designer design for recycling (DFR), design for energy (DFE) and Eco-design.

Testing the Equality of Several Correlation Coefficients by Permutation Method

  • Um, Yonghwan
    • Journal of the Korea Society of Computer and Information
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    • v.27 no.6
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    • pp.167-174
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    • 2022
  • In this paper we investigate the permutation test for the equality of correlation coefficients in several independent populations. Permutation test is a non-parametric testing methodology based upon the exchangeability of observations. Exchangeability is a generalization of the concept of independent, identically distributed random variables. Using permutation method, we may construct asymptotically exact test. This method is asymptotically as powerful as standard parametric tests and is a valuable tool when the sample sizes are small and normality assumption cannot be met. We first review existing parametric approaches to test the equality of correlation coefficients and compare them with the permutation test. At the end, all the approaches are illustrated using Iris data example.

Stochastic Comparisons of Order Statistics under Non-standard Conditions

  • Kim, S. H.
    • Communications for Statistical Applications and Methods
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    • v.3 no.2
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    • pp.187-195
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    • 1996
  • This paper deals with the stochastic comparisons of order statistics from independent but nonidentically distributed (i.n.i.d) variates. And we consider order statistics under positive dependence, negative dependence, and exchangeability.

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Bayesian Methods for Combining Results from Different Experiments

  • Lee, In-Suk;Kim, Dal-Ho;Lee, Keun-Baik
    • Communications for Statistical Applications and Methods
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    • v.6 no.1
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    • pp.181-191
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    • 1999
  • We consider Bayesian models allow multiple grouping of parameters for the normal means estimation problem. In particular, we consider a typical Bayesian hierarchical approach based on thepartial exchangeability where the components within a subgroup are exchangeable, but the different subgroups are not. We discuss implementation of such Bayesian procedures via Gibbs sampling. We illustrate the proposed methods with numerical examples.

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A Simple Method for the Prepartion of Handmade Blowgun (간편한 Blowgun의 제작법)

  • Shin Sang-Tae
    • Journal of Veterinary Clinics
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    • v.4 no.1
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    • pp.433-438
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    • 1987
  • A cheap, simple, and exact method for the preparation of handmade blowgun was studied. The blowgun-dart-adhesive -stand made of plastic syringe shaft was simple and convenient to make a blowgun dart accuratly. The needle end sealing method with wire-lead(solder) made the needle good to secure and simple to make. Because of easy exchangeability, the tail-piece made of yarn and a rivet is able to use permanently. And the materials of this blowgun were inexpensive, common and easily obtainable. This blowgun dart had various capacity up to 12ml.

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The Heavy Metal Adsorption Properties of Hydroxyapatite Powders Synthesized by Precipitation Reaction Method and Its Applicability for the Removal Agents of Noxious Metallic Ions in Waste Water (침전반응법으로 합성한 수산아파타이트 분말의 중금속 흡착 특성 및 폐수중의 유해 금속 제거제로서의 유용성)

  • Lee, Mu Seong;Na, Choon Ki;Lee, Mi Suk;Kim, Oak Bae;Kim, Moon Young
    • Economic and Environmental Geology
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    • v.28 no.3
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    • pp.231-241
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    • 1995
  • It is well known that hydroxyapatite [$Ca_{10}(PO_4)_6(OH)_2$] have an exchangeability for various heavy metal ions in aqueous solution. To evalute the feasibility of employing the synthetic hydroxyapatites as an eliminatable exchanger for environmentally noxious caions in waste water, the adsorption properties, the removal capacities and the selectivity of the apatites for various cations were investigated in more detailed. The heavy metal cations have been exchanged in calcium part of hydroxyapatite. The order of the degree of amount exchanged of the investigated cations is $Pb^{2+}>Cd^{2+}>Zn^{2+}>Ba^{2+}$. The molar ratios between released $Cd^{2+}$ ions and remeved divalent metal cations in the reacted solution with hydroxyapatite are roughly close to an integer 1.0, suggesting that an ion-exchange reaction could have played a major role in the removal of heavy metals rather then an adsorption effect. The exchangeability of the hydroxyapatite powder of Ca/P molar ratio 1.67, which have specipic surface area of $104.5m^2g^{-1}$, appeared to be better then $237.6{\mu}g$ per g for $Pb^{2+}$ ions. The removal capacity of the heavy metal ions varies directly as particle size of hydroxyapatites. All evidences obtained indicate that the synthesized hydroxyapatite powders by precipitation reaction method can be employed as an effective cation exchanger for eliminating noxious ions in waste water even in some improvemental.

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Bayesian methods in clinical trials with applications to medical devices

  • Campbell, Gregory
    • Communications for Statistical Applications and Methods
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    • v.24 no.6
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    • pp.561-581
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    • 2017
  • Bayesian statistics can play a key role in the design and analysis of clinical trials and this has been demonstrated for medical device trials. By 1995 Bayesian statistics had been well developed and the revolution in computing powers and Markov chain Monte Carlo development made calculation of posterior distributions within computational reach. The Food and Drug Administration (FDA) initiative of Bayesian statistics in medical device clinical trials, which began almost 20 years ago, is reviewed in detail along with some of the key decisions that were made along the way. Both Bayesian hierarchical modeling using data from previous studies and Bayesian adaptive designs, usually with a non-informative prior, are discussed. The leveraging of prior study data has been accomplished through Bayesian hierarchical modeling. An enormous advantage of Bayesian adaptive designs is achieved when it is accompanied by modeling of the primary endpoint to produce the predictive posterior distribution. Simulations are crucial to providing the operating characteristics of the Bayesian design, especially for a complex adaptive design. The 2010 FDA Bayesian guidance for medical device trials addressed both approaches as well as exchangeability, Type I error, and sample size. Treatment response adaptive randomization using the famous extracorporeal membrane oxygenation example is discussed. An interesting real example of a Bayesian analysis using a failed trial with an interesting subgroup as prior information is presented. The implications of the likelihood principle are considered. A recent exciting area using Bayesian hierarchical modeling has been the pediatric extrapolation using adult data in clinical trials. Historical control information from previous trials is an underused area that lends itself easily to Bayesian methods. The future including recent trends, decision theoretic trials, Bayesian benefit-risk, virtual patients, and the appalling lack of penetration of Bayesian clinical trials in the medical literature are discussed.

Research of Knowledge Management and Reusability in Streaming Big Data with Privacy Policy through Actionable Analytics (스트리밍 빅데이터의 프라이버시 보호 동반 실용적 분석을 통한 지식 활용과 재사용 연구)

  • Paik, Juryon;Lee, Youngsook
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.12 no.3
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    • pp.1-9
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    • 2016
  • The current meaning of "Big Data" refers to all the techniques for value eduction and actionable analytics as well management tools. Particularly, with the advances of wireless sensor networks, they yield diverse patterns of digital records. The records are mostly semi-structured and unstructured data which are usually beyond of capabilities of the management tools. Such data are rapidly growing due to their complex data structures. The complex type effectively supports data exchangeability and heterogeneity and that is the main reason their volumes are getting bigger in the sensor networks. However, there are many errors and problems in applications because the managing solutions for the complex data model are rarely presented in current big data environments. To solve such problems and show our differentiation, we aim to provide the solution of actionable analytics and semantic reusability in the sensor web based streaming big data with new data structure, and to empower the competitiveness.

Bayesian pooling for contingency tables from small areas

  • Jo, Aejung;Kim, Dal Ho
    • Journal of the Korean Data and Information Science Society
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    • v.27 no.6
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    • pp.1621-1629
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    • 2016
  • This paper studies Bayesian pooling for analysis of categorical data from small areas. Many surveys consist of categorical data collected on a contingency table in each area. Statistical inference for small areas requires considerable care because the subpopulation sample sizes are usually very small. Typically we use the hierarchical Bayesian model for pooling subpopulation data. However, the customary hierarchical Bayesian models may specify more exchangeability than warranted. We, therefore, investigate the effects of pooling in hierarchical Bayesian modeling for the contingency table from small areas. In specific, this paper focuses on the methods of direct or indirect pooling of categorical data collected on a contingency table in each area through Dirichlet priors. We compare the pooling effects of hierarchical Bayesian models by fitting the simulated data. The analysis is carried out using Markov chain Monte Carlo methods.

Bayesian Method for Combining Results from Different Poisson Experiments

  • Cho, Jang Sik;Kim, Dal Ho
    • Communications for Statistical Applications and Methods
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    • v.7 no.2
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    • pp.533-540
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    • 2000
  • The problem of information related to I poission experiments, each having a distinct failure rate $\theta$i I=1,2,…,I, is considered. Instead of using a standard exchangeable prior for $\theta$=($\theta$1,$\theta$2,…,$\theta$I), we consider a partition of the experiments and take the $\theta$i's belonging to the same partition subgroup to be exchangeable and the $\theta$i's belonging to distinct subgroups to be independent. And we perform Gibbs sampling approach for Bayesian inference on $\theta$ conditional on a partition. Numerical study using real data is provided.

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