• 제목/요약/키워드: Prior

검색결과 11,949건 처리시간 0.035초

Background Prior-based Salient Object Detection via Adaptive Figure-Ground Classification

  • Zhou, Jingbo;Zhai, Jiyou;Ren, Yongfeng;Lu, Ali
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • 제12권3호
    • /
    • pp.1264-1286
    • /
    • 2018
  • In this paper, a novel background prior-based salient object detection framework is proposed to deal with images those are more complicated. We take the superpixels located in four borders into consideration and exploit a mechanism based on image boundary information to remove the foreground noises, which are used to form the background prior. Afterward, an initial foreground prior is obtained by selecting superpixels that are the most dissimilar to the background prior. To determine the regions of foreground and background based on the prior of them, a threshold is needed in this process. According to a fixed threshold, the remaining superpixels are iteratively assigned based on their proximity to the foreground or background prior. As the threshold changes, different foreground priors generate multiple different partitions that are assigned a likelihood of being foreground. Last, all segments are combined into a saliency map based on the idea of similarity voting. Experiments on five benchmark databases demonstrate the proposed method performs well when it compares with the state-of-the-art methods in terms of accuracy and robustness.

초기 소성변형이 초미세 결정립 페라이트-마르텐사이트 이상조직 탄소강의 건식 미끄럼마멸 특성에 미치는 영향 (Effect of Prior Deformation on the Sliding Wear of Ultra-fine Grained Ferrite-Martensite Dual Phase Steel)

  • 박준기;이슬기;신동혁;김용석
    • 한국소성가공학회:학술대회논문집
    • /
    • 한국소성가공학회 2008년도 춘계학술대회 논문집
    • /
    • pp.521-524
    • /
    • 2008
  • Effect of prior deformation on the sliding wear of the ultra-fine grained (UFG) ferrite-martensite dual phase (DP) steel was investigated. The UFG DP steel was fabricated by the ECAP and subsequent intercritical annealing. The steel was cold rolled before the wear test, and the effect of the prior deformation on the wear was examined. The wear tests were carried out at various loads against a bearing steel ball. The wear rate of the UFG DP steel that did not experience the prior deformation was higher than that of the coarse-grained (CG) DP steel, because of more severe surface shear deformation. The wear rate of the specimens with prior deformation was much higher than that of the specimen without prior deformation. The deformed CG DP specimen showed higher rate than the deformed UFG DP specimen, and the rate-variation of the CG DP steel was much bigger under the same test condition.

  • PDF

Bayesian hypothesis testing for homogeneity of coecients of variation in k Normal populationsy

  • Kang, Sang-Gil
    • Journal of the Korean Data and Information Science Society
    • /
    • 제21권1호
    • /
    • pp.163-172
    • /
    • 2010
  • In this paper, we deal with the problem for testing homogeneity of coecients of variation in several normal distributions. We propose Bayesian hypothesis testing procedures based on the Bayes factor under noninformative prior. The noninformative prior is usually improper which yields a calibration problem that makes the Bayes factor to be dened up to a multiplicative constant. So we propose the objective Bayesian hypothesis testing procedures based on the fractional Bayes factor and the intrinsic Bayes factor under the reference prior. Simulation study and a real data example are provided.

Reference Priors in a Two-Way Mixed-Effects Analysis of Variance Model

  • 장인홍;김병휘
    • Journal of the Korean Data and Information Science Society
    • /
    • 제13권2호
    • /
    • pp.317-328
    • /
    • 2002
  • We first derive group ordering reference priors in a two-way mixed-effects analysis of variance (ANOVA) model. We show that posterior distributions are proper and provide marginal posterior distributions under reference priors. We also examine whether the reference priors satisfy the probability matching criterion. Finally, the reference prior satisfying the probability matching criterion is shown to be good in the sense of frequentist coverage probability of the posterior quantile.

  • PDF

Noninformative Priors for Step Stress Accelerated Life Tests in Exponential Distribution

  • 이우동;박홍경
    • 한국산업정보학회:학술대회논문집
    • /
    • 한국산업정보학회 2009년도 춘계학술대회 미래 IT융합기술 및 전략
    • /
    • pp.107-113
    • /
    • 2009
  • This paper deals with noninformative priors for such as Jeffres' prior, reference prior and probability matching prior for scale parameter of exponential distribution when the data are collected in multiple step stress accelerated life tests. We find the noninformative priors for this model and show that the reference prior satisfies first order matching criterion. Using artificial data, we perform Bayesian analysis for proposed priors.

  • PDF

Discontinuity of Representativeness Heuristic

  • 이호창
    • 경영과학
    • /
    • 제16권1호
    • /
    • pp.101-113
    • /
    • 1999
  • The individual behavior on considering prior information when one assesses the probability of uncertain event by representativeness heuristic has been investigated. While prior researches proposed two contrasting behaviors on the employment, we tested the mixed hypothesis that individual ignores the prior information to some extents and begins to consider it above certain threshold when the evidence of representativeness is not salient. The threshold effect of prior probability is positively experimented and the results strongly support the discontinuity hypothesis of representativeness heuristic.

  • PDF

Bayesian Inference for Stress-Strength Systems

  • Chang, In-Hong;Kim, Byung-Hwee
    • 한국데이터정보과학회:학술대회논문집
    • /
    • 한국데이터정보과학회 2005년도 추계학술대회
    • /
    • pp.27-34
    • /
    • 2005
  • We consider the problem of estimating the system reliability noninformative priors when both stress and strength follow generalized gamma distributions. We first derive Jeffreys' prior, group ordering reference priors, and matching priors. We investigate the propriety of posterior distributions and provide marginal posterior distributions under those noninformative priors. We also examine whether the reference priors satisfy the probability matching criterion.

  • PDF

DEVELOPING NONINFORMATIVE PRIORS FOR THE FAMILIAL DATA

  • Heo, Jung-Eun;Kim, Yeong-Hwa
    • Journal of the Korean Statistical Society
    • /
    • 제36권1호
    • /
    • pp.77-91
    • /
    • 2007
  • This paper considers development of noninformative priors for the familial data when the families have equal number of offspring. Several noninformative priors including the widely used Jeffreys' prior as well as the different reference priors are derived. Also, a simultaneously-marginally-probability-matching prior is considered and probability matching priors are derived when the parameter of interest is inter- or intra-class correlation coefficient. The simulation study implemented by Gibbs sampler shows that two-group reference prior is slightly edge over the others in terms of coverage probability.

베이즈의 균일분포에 관한 소고 (On Bayes' uniform prior)

  • 허명회
    • 응용통계연구
    • /
    • 제7권2호
    • /
    • pp.263-268
    • /
    • 1994
  • 베이스(Thomas Bayes)는 역사적인 1764년 논문에서 공 W의 위치 $\theta$에 대한 추론 문제를 생각한 바 있다. 이 때 그는 $\theta$에 대한 사전(prior) 분포로서 균일(uniform) 분포를 가정하였는데, 본 소고에서는 이 사전분포가 단순한 주관적 확률이 아닌 논리적 확률로 간주될 수 있음을 보일 것이다.

  • PDF

Bayesian Hypothesis Testing for the Difference of Quantiles in Exponential Models

  • Kang, Sang-Gil
    • Journal of the Korean Data and Information Science Society
    • /
    • 제19권4호
    • /
    • pp.1379-1390
    • /
    • 2008
  • This article deals with the problem of testing the difference of quantiles in exponential distributions. We propose Bayesian hypothesis testing procedures for the difference of two quantiles under the noninformative prior. The noninformative prior is usually improper which yields a calibration problem that makes the Bayes factor to be defined up to a multiplicative constant. So we propose the objective Bayesian hypothesis testing procedures based on the fractional Bayes factor and the intrinsic Bayes factor under the matching prior. Simulation study and a real data example are provided.

  • PDF