• Title/Summary/Keyword: joint bayesian

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The remarkable story of Portogruaro Civic Tower's probabilistic health monitoring

  • Zonta, Daniele;Pozzi, Matteo
    • Structural Monitoring and Maintenance
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    • v.2 no.4
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    • pp.301-318
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    • 2015
  • This is the story of a bell-tower and its monitoring. The Civic Tower in Portogruaro is a 59 m high masonry bell-tower, originally built in the XIII century, today leaning more than a meter out of plumb. Since 2003, the building inclination has been continuously monitored with an optical inclinometer in an effort to see whether the tilt is still in progress. When the monitoring started, it was thought highly unlikely that the Tower would tilt further. After three years of monitoring and historical investigation, this idea was completely overturned. We show here how the initial view developed to a final awareness via a probabilistic analysis of the information acquired, based on Bayesian logic. We illustrate how the joint use of instrumental monitoring and historical documentation allowed timely recognition of signs of ongoing tilting and accurate calculation not only of the mean inclination trend, but also the credibility of this information.

BAYESIAN INFERENCE FOR THE POWER LAW PROCESS WITH THE POWER PRIOR

  • KIM HYUNSOO;CHOI SANGA;KIM SEONG W.
    • Journal of the Korean Statistical Society
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    • v.34 no.4
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    • pp.331-344
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    • 2005
  • Inference on current data could be more reliable if there exist similar data based on previous studies. Ibrahim and Chen (2000) utilize these data to characterize the power prior. The power prior is constructed by raising the likelihood function of the historical data to the power $a_o$, where $0\;{\le}\;a_o\;{\le}\;1$. The power prior is a useful informative prior in Bayesian inference. However, for model selection or model comparison problems, the propriety of the power prior is one of the critical issues. In this paper, we suggest two joint power priors for the power law process and show that they are proper under some conditions. We demonstrate our results with a real dataset and some simulated datasets.

Bayesian Estimations of the Smaller and Larger for Two Pareto Scale Parameters

  • Woo, Jungsoo;Lee, Changsoo
    • Communications for Statistical Applications and Methods
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    • v.7 no.3
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    • pp.829-836
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    • 2000
  • We shall derive Bayes estimators for he smaller and larger of two Pareto scale parameters with a common known shape parameter when the order of the scales is unknown and sample sizes are equal under squared error loss function. Also, we shall obtain biases and man squared errors for proposed Bayes estimators, and compare numerically performances for the proposed Bayes estimators.

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Transformation of Mass Function and Joint Mass Function for Evidence Theory

  • Suh, Doug. Y.;Esogbue, Augustine O.
    • Journal of the Korean Institute of Intelligent Systems
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    • v.1 no.2
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    • pp.16-34
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    • 1991
  • It has been widely accepted that expert systems must reason from multiple sources of information that is to some degree evidential - uncertain, imprecise, and occasionally inaccurate - called evidential information. Evidence theory (Dempster/Shafet theory) provides one of the most general framework for representing evidential information compared to its alternatives such as Bayesian theory or fuzzy set theory. Many expert system applications require evidence to be specified in the continuous domain - such as time, distance, or sensor measurements. However, the existing evidence theory does not provide an effective approach for dealing with evidence about continuous variables. As an extension to Strat's pioneeiring work, this paper provides a new combination rule, a new method for mass function transffrmation, and a new method for rendering joint mass fuctions which are of great utility in evidence theory in the continuous domain.

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Implementation of a Face Authentication Embedded System Using High-dimensional Local Binary Pattern Descriptor and Joint Bayesian Algorithm (고차원 국부이진패턴과 결합베이시안 알고리즘을 이용한 얼굴인증 임베디드 시스템 구현)

  • Kim, Dongju;Lee, Seungik;Kang, Seog Geun
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.21 no.9
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    • pp.1674-1680
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    • 2017
  • In this paper, an embedded system for face authentication, which exploits high-dimensional local binary pattern (LBP) descriptor and joint Bayesian algorithm, is proposed. We also present a feasible embedded system for the proposed algorithm implemented with a Raspberry Pi 3 model B. Computer simulation for performance evaluation of the presented face authentication algorithm is carried out using a face database of 500 persons. The face data of a person consist of 2 images, one for training and the other for test. As performance measures, we exploit score distribution and face authentication time with respect to the dimensions of principal component analysis (PCA). As a result, it is confirmed that an embedded system having a good face authentication performance can be implemented with a relatively low cost under an optimized embedded environment.

Estimation of Interaction Effects among Nucleotide Sequence Variants in Animal Genomes

  • Lee, Chaeyoung;Kim, Younyoung
    • Asian-Australasian Journal of Animal Sciences
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    • v.22 no.1
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    • pp.124-130
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    • 2009
  • Estimating genetic interaction effects in animal genomics would be one of the most challenging studies because the phenotypic variation for economically important traits might be largely explained by interaction effects among multiple nucleotide sequence variants under various environmental exposures. Genetic improvement of economic animals would be expected by understanding multi-locus genetic interaction effects associated with economic traits. Most analyses in animal breeding and genetics, however, have excluded the possibility of genetic interaction effects in their analytical models. This review discusses a historical estimation of the genetic interaction and difficulties in analyzing the interaction effects. Furthermore, two recently developed methods for assessing genetic interactions are introduced to animal genomics. One is the restricted partition method, as a nonparametric grouping-based approach, that iteratively utilizes grouping of genotypes with the smallest difference into a new group, and the other is the Bayesian method that draws inferences about the genetic interaction effects based on their marginal posterior distributions and attains the marginalization of the joint posterior distribution through Gibbs sampling as a Markov chain Monte Carlo. Further developing appropriate and efficient methods for assessing genetic interactions would be urgent to achieve accurate understanding of genetic architecture for complex traits of economic animals.

Deep Image Annotation and Classification by Fusing Multi-Modal Semantic Topics

  • Chen, YongHeng;Zhang, Fuquan;Zuo, WanLi
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.12 no.1
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    • pp.392-412
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    • 2018
  • Due to the semantic gap problem across different modalities, automatically retrieval from multimedia information still faces a main challenge. It is desirable to provide an effective joint model to bridge the gap and organize the relationships between them. In this work, we develop a deep image annotation and classification by fusing multi-modal semantic topics (DAC_mmst) model, which has the capacity for finding visual and non-visual topics by jointly modeling the image and loosely related text for deep image annotation while simultaneously learning and predicting the class label. More specifically, DAC_mmst depends on a non-parametric Bayesian model for estimating the best number of visual topics that can perfectly explain the image. To evaluate the effectiveness of our proposed algorithm, we collect a real-world dataset to conduct various experiments. The experimental results show our proposed DAC_mmst performs favorably in perplexity, image annotation and classification accuracy, comparing to several state-of-the-art methods.

Trajectory Recognition and Tracking for Condensation Algorithm and Fuzzy Inference (Condensation 알고리즘과 퍼지 추론을 이용한 이동물체의 궤적인식 및 추적)

  • Kang, Suk-Bum;Yang, Tae-Kyu
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.11 no.2
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    • pp.402-409
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    • 2007
  • In this paper recognized for trajectory using Condensation algorithm. In this pater used fuzzy controller for recognized trajectory using fuzzy reasoning. The fuzzy system tract to the three-dimensional space for raw and roll movement. The joint angle ${\theta}_1$ of the manipulator rotate from $0^{\circ}\;to\;360^{\circ}$, and the joint angle ${\theta}_2$ rotate from $0^{\circ}\;to\;180^{\circ}$. The moving object of velocity display for recognition without error using Condensation algorithm. The tracking system demonstrated the reliability of proposed algorithm through simulation against used trajectory.

Quantitative analysis of drought propagation probabilities combining Bayesian networks and copula function (베이지안 네트워크와 코플라 함수의 결합을 통한 가뭄전이 발생확률의 정량적 분석)

  • Shin, Ji Yae;Ryu, Jae Hee;Kwon, Hyun-Han;Kim, Tae-Woong
    • Journal of Korea Water Resources Association
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    • v.54 no.7
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    • pp.523-534
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    • 2021
  • Meteorological drought originates from a precipitation deficiency and propagates to agricultural and hydrological droughts through the hydrological cycle. Comparing with the meteorological drought, agricultural and hydrological droughts have more direct impacts on human society. Thus, understanding how meteorological drought evolves to agricultural and hydrological droughts is necessary for efficient drought preparedness and response. In this study, meteorological and hydrological droughts were defined based on the observed precipitation and the synthesized streamflow by the land surface model. The Bayesian network model was applied for probabilistic analysis of the propagation relationship between meteorological and hydrological droughts. The copula function was used to estimate the joint probability in the Bayesian network. The results indicated that the propagation probabilities from the moderate and extreme meteorological droughts were ranged from 0.41 to 0.63 and from 0.83 to 0.98, respectively. In addition, the propagation probabilities were highest in autumn (0.71 ~ 0.89) and lowest in winter (0.41 ~ 0.62). The propagation probability increases as the meteorological drought evolved from summer to autumn, and the severe hydrological drought could be prevented by appropriate mitigation during that time.

A State-space Production Assessment Model with a Joint Prior Based on Population Resilience: Illustration with the Common Squid Todarodes pacificus Stock (자원복원력 개념을 적용한 사전확률분포 및 상태공간 잉여생산 평가모델: 살오징어(Todarodes pacificus) 개체군 자원평가)

  • Gim, Jinwoo;Hyun, Saang-Yoon;Yoon, Sang Chul
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.55 no.2
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    • pp.183-188
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    • 2022
  • It is a difficult task to estimate parameters in even a simple stock assessment model such as a surplus production model, using only data about temporal catch-per-unit-effort (CPUE) (or survey index) and fishery yields. Such difficulty is exacerbated when time-varying parameters are treated as random effects (aka state variables). To overcome the difficulty, previous studies incorporated somewhat subjective assumptions (e.g., B1=K) or informative priors of parameters. A key is how to build an objective joint prior of parameters, reducing subjectivity. Given the limited data on temporal CPUEs and fishery yields from 1999-2020 for common squid Todarodes pacificus, we built a joint prior of only two parameters, intrinsic growth rate (r) and carrying capacity (K), based on the resilience level of the population (Froese et al., 2017), and used a Bayesian state-space production assessment model. We used template model builder (TMB), a R package for implementing the assessment model, and estimating all parameters in the model. The predicted annual biomass was in the range of 0.76×106 to 4.06×106 MT, the estimated MSY was 0.13×106 MT, the estimated r was 0.24, and the estimated K was 2.10×106 MT.