• Title/Summary/Keyword: RAO

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Lifetime Estimation for Mixed Replacement Grouped Data in Competing Failures Model

  • Lee, Tai-Sup;Yun, Sang-Un
    • International Journal of Reliability and Applications
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    • v.2 no.3
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    • pp.189-197
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    • 2001
  • The estimation of mean lifetimes in presence of interval censoring with mixed replacement procedure is examined when the distributions of lifetimes are exponential. It is assumed that, due to physical restrictions and/or economic constraints, the number of failures is investigated only at several inspection times during the lifetime test; thus there is interval censoring. The maximum likelihood estimator is found in an implicit form. The Cramor-Rao lower bound, which is the asymptotic variance of the estimator, is derived. The estimation of mean lifetimes for competing failures model has been expanded.

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Statistical Location Estimation in Container-Grown Seedlings Based on Wireless Sensor Networks

  • Lee, Sang-Hyun;Moon, Kyung-Il
    • International Journal of Advanced Culture Technology
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    • v.2 no.2
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    • pp.15-18
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    • 2014
  • This paper presents a sensor location decision making method respect to Container-Grown Seedlings in view of precision agriculture (PA) when sensors involved in tree container measure received signal strength (RSS) or time-of-arrival (TOA) between themselves and neighboring sensors. A small fraction of sensors in the container-grown seedlings system have a known location, whereas the remaining locations must be estimated. We derive Rao-Cramer bounds and maximum-likelihood estimators under Gaussian and log-normal models for the TOA and RSS measurements, respectively.

ON FUZZY k−IDEALS, k−FUZZY IDEALS AND FUZZY 2−PRIME IDEALS IN Γ−SEMIRINGS

  • Murali Krishna Rao, M.;Venkateswarlu, B.
    • Journal of applied mathematics & informatics
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    • v.34 no.5_6
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    • pp.405-419
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    • 2016
  • The notion of Γ-semiring was introduced by M. Murali Krishna Rao [8] as a generalization of Γ-ring as well as of semiring. In this paper fuzzy k-ideals, k-fuzzy ideals and fuzzy-2-prime ideals in Γ-semirings have been introduced and study the properties related to them. Let μ be a fuzzy k-ideal of Γ-semiring M with |Im(μ)| = 2 and μ(0) = 1. Then we establish that Mμ is a 2-prime ideal of Γ-semiring M if and only if μ is a fuzzy prime ideal of Γ-semiring M.

Likelihood Based Confidence Intervals for the Difference of Proportions in Two Doubly Sampled Data with a Common False-Positive Error Rate

  • Lee, Seung-Chun
    • Communications for Statistical Applications and Methods
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    • v.17 no.5
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    • pp.679-688
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    • 2010
  • Lee (2010) developed a confidence interval for the difference of binomial proportions in two doubly sampled data subject to false-positive errors. The confidence interval seems to be adequate for a general double sampling model subject to false-positive misclassification. However, in many applications, the false-positive error rates could be the same. On this note, the construction of asymptotic confidence interval is considered when the false-positive error rates are common. The coverage behaviors of nine likelihood based confidence intervals are examined. It is shown that the confidence interval based Rao score with the expected information has good performance in terms of coverage probability and expected width.

A Rao-Robson Chi-Square Test for Multivariate Normality Based on the Mahalanobis Distances

  • Park, Cheolyong
    • Communications for Statistical Applications and Methods
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    • v.7 no.2
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    • pp.385-392
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    • 2000
  • Many tests for multivariate normality are based on the spherical coordinates of the scaled residuals of multivariate observations. Moore and Stubblebine's (1981) Pearson chi-square test is based on the radii of the scaled residuals, or equivalently the sample Mahalanobis distances of the observations from the sample mean vector. The chi-square statistic does not have a limiting chi-square distribution since the unknown parameters are estimated from ungrouped data. We will derive a simple closed form of the Rao-Robson chi-square test statistic and provide a self-contained proof that it has a limiting chi-square distribution. We then provide an illustrative example of application to a real data with a simulation study to show the accuracy in finite sample of the limiting distribution.

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Evaluation and Selection of Potential Parents Based on Selection Indices and Isozyme Variability in Silkworm, Bombyx mori, L.

  • Moorthy S.M.;Das S.K.;Rao, P.R.T.;Urs S. Rao,;Sarkar A.
    • International Journal of Industrial Entomology and Biomaterials
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    • v.14 no.1
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    • pp.1-7
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    • 2007
  • In order to find out the appropriate parents for the breeding programme, twelve bivoltine and three multivoltine silkworm breeds were evaluated on the basis of multivariate selection index and isozyme analysis. Of which, four [CSR2, D6 (P), SK3, SK4] bivoltine and two multivoltine (Nistari, Cambodge) breeds were selected and breeding initiated to develop higher survival bivoltine silkworm breed suitable for tropical conditions. Among two isozyme (Esterase and acid phosphatase) analyzed, only esterase exhibited polymorphism among the bivoltine breeds. No polymorphism was observed among multivoltine in respect of esterase as well as acid phosphatase.

Secret Key Generation from Common Randomness over Ultra-wideband Wireless Channels

  • Huang, Jing Jing;Jiang, Ting
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.8 no.10
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    • pp.3557-3571
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    • 2014
  • We develop a secret key generation scheme using phase estimation in ultra-wideband (UWB) wireless fading channels. Based on the reciprocity theorem, two terminals extract the phase of the channel as a common random source to generate secret bits. Moreover, we study the secret key rate by a pair of nodes observing correlated sources and communicating to achieve secret key agreement over public communication channels. As our main results, we establish a more practical upper bound from Cramer-Rao bound (CRB) and compare it with a universally theoretical upper bound on the shared maximum key rate from mutual information of correlated random sources. Derivation and numerical examples are presented to demonstrate the bound. Simulation studies are also provided to validate feasibility and efficiency of the proposed scheme.

CERTAIN HYPERGEOMETRIC IDENTITIES DEDUCIBLE BY USING THE BETA INTEGRAL METHOD

  • Choi, Junesang;Rathie, Arjun K.;Srivastava, Hari M.
    • Bulletin of the Korean Mathematical Society
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    • v.50 no.5
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    • pp.1673-1681
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    • 2013
  • The main objective of this paper is to show how one can obtain eleven new and interesting hypergeometric identities in the form of a single result from the old ones by mainly employing the known beta integral method which was recently introduced and used in a systematic manner by Krattenthaler and Rao [6]. The results are derived with the help of a generalization of a well-known hypergeometric transformation formula due to Kummer. Several identities including one obtained earlier by Krattenthaler and Rao [6] follow as special cases of our main results.