• Title/Summary/Keyword: Nuisance parameter

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Improving $L_1$ Information Bound in the Presence of a Nuisance Parameter for Median-unbiased Estimators

  • Sung, Nae-Kyung
    • Journal of the Korean Statistical Society
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    • v.22 no.1
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    • pp.1-12
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    • 1993
  • An approach to make the information bound sharper in median-unbiased estimation, based on an analogue of the Cramer-Rao inequality developed by Sung et al. (1990), is introduced for continuous densities with a nuisance parameter by considering information quantities contained both in the parametric function of interest and in the nuisance parameter in a linear fashion. This approach is comparable to that of improving the information bound in mean-unbiased estimation for the case of two unknown parameters. Computation of an optimal weight corresponding to the nuisance parameter is also considered.

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Genetic association tests when a nuisance parameter is not identifiable under no association

  • Kim, Wonkuk;Kim, Yeong-Hwa
    • Communications for Statistical Applications and Methods
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    • v.24 no.6
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    • pp.663-671
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    • 2017
  • Some genetic association tests include an unidentifiable nuisance parameter under the null hypothesis of no association. When the mode of inheritance (MOI) is not specified in a case-control design, the Cochran-Armitage (CA) trend test contains an unidentifiable nuisance parameter. The transmission disequilibrium test (TDT) in a family-based association study that includes the unaffected also contains an unidentifiable nuisance parameter. The hypothesis tests that include an unidentifiable nuisance parameter are typically performed by taking a supremum of the CA tests or TDT over reasonable values of the parameter. The p-values of the supremum test statistics cannot be obtained by a normal or chi-square distribution. A common method is to use a Davies's upper bound of the p-value instead of an exact asymptotic p-value. In this paper, we provide a unified sine-cosine process expression of the CA trend test that does not specify the MOI and the TDT that includes the unaffected. We also present a closed form expression of the exact asymptotic formulas to calculate the p-values of the supremum tests when the score function can be written as a linear form in an unidentifiable parameter. We illustrate how to use the derived formulas using a pharmacogenetics case-control dataset and an attention deficit hyperactivity disorder family-based example.

Inference about Measure of Agreement in the General Mixture Model via Parameter Orthogonalization

  • Um, Jongseok
    • Communications for Statistical Applications and Methods
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    • v.10 no.2
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    • pp.341-352
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    • 2003
  • Collecting data through experiment, the observers are an import source of measurement error and the inference on the measure of agreement, say kappa, is necessary. The models commonly used are complicated general mixture model, which have many nuisance parameters. Orthogonalization of parameters reduce the effect of nuisance parameter. Orthogonalization of estimating function gives the same effect as the parameter orthogonalization. In this study, the method for orthogonalization of estimating equation is studied and applied to the Beta-binomial model to examine the properties of the estimate of kappa. As a result, the likelihood function is insensitive to the change of the nuisance parameter and bias is smaller than the result of m.1.e. when kappa has extreme values

Lie Detection Technique using Video from the Ratio of Change in the Appearance

  • Hossain, S.M. Emdad;Fageeri, Sallam Osman;Soosaimanickam, Arockiasamy;Kausar, Mohammad Abu;Said, Aiman Moyaid
    • International Journal of Computer Science & Network Security
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    • v.22 no.7
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    • pp.165-170
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    • 2022
  • Lying is nuisance to all, and all liars knows it is nuisance but still keep on lying. Sometime people are in confusion how to escape from or how to detect the liar when they lie. In this research we are aiming to establish a dynamic platform to identify liar by using video analysis especially by calculating the ratio of changes in their appearance when they lie. The platform will be developed using a machine learning algorithm along with the dynamic classifier to classify the liar. For the experimental analysis the dataset to be processed in two dimensions (people lying and people tell truth). Both parameter of facial appearance will be stored for future identification. Similarly, there will be standard parameter to be built for true speaker and liar. We hope this standard parameter will be able to diagnosed a liar without a pre-captured data.

Test in Unbalanced Panel Regression Model with Nuisance Parameter (장애모수가 존재하는 불균형 패널회귀모형에서의 검정법)

  • 이재원;정병철;송석헌
    • The Korean Journal of Applied Statistics
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    • v.17 no.3
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    • pp.547-556
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    • 2004
  • This paper consider the testing problem of variance component for the unbalanced two-way error component model with nuisance parameter. We derive the one-sided LM test statistic for testing zero individual(time) effects assuming that the other time-specific(individual) effects are present. Using the Monte Carlo experiments, the computational more demanding LR test slightly underestimates the nominal size and has the low powers relative to LM test statistic.

Asymptotics for realized covariance under market microstructure noise and sampling frequency determination

  • Shin, Dong Wan;Hwang, Eunju
    • Communications for Statistical Applications and Methods
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    • v.23 no.5
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    • pp.411-421
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    • 2016
  • Large frequency limiting distributions of two errors in realized covariance are investigated under noisy and non-synchronous high frequency sampling situations. The first distribution characterizes increased variance of the realized covariance due to noise for large frequency and the second distribution characterizes decreased variance of the realized covariance due to discretization for large frequency. The distribution of the combined error enables us to determine the sampling frequency which depends on a nuisance parameter. A consistent estimator of the nuisance parameter is proposed.

Convergence of Score process in the Cox Proportional Hazards Model

  • Hwang, Jin-Soo
    • Journal of the Korean Statistical Society
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    • v.26 no.1
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    • pp.117-130
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    • 1997
  • We study the asymptotic behavior of the maximum partial likelihood estimator in the Cox proportional hazards model in the presence of nuisance parameters when the entry of patients is staggered. When entry of patients is simultaneous and there is only one regression parameter in the Cox model, the efficient score process of the partial likelihood is martingale and converges weakly to a time-chnaged Brownian motion. Our problem is to get a similar result in the presence of nuisance parameters when entry of patient is staggered.

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AN ADAPTIVE SEQUENTIAL PROBABILITY RATIO TEST IN THE AUTOREGRESSIVE PROCESS

  • Choi, Ki-Heon
    • Journal of applied mathematics & informatics
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    • v.11 no.1_2
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    • pp.373-378
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    • 2003
  • consider the problem of sequentially hypotheses about a parameter $\theta$ in the presence of the nuisance parameter $\rho$. and we investigate further to computing the error probabilities and expected sample sizes in the frequentist properties of the adaptive S.P.R.T. for $\theta$.

Estimation on a two-parameter Rayleigh distribution under the progressive Type-II censoring scheme: comparative study

  • Seo, Jung-In;Seo, Byeong-Gyu;Kang, Suk-Bok
    • Communications for Statistical Applications and Methods
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    • v.26 no.2
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    • pp.91-102
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    • 2019
  • In this paper, we propose a new estimation method based on a weighted linear regression framework to obtain some estimators for unknown parameters in a two-parameter Rayleigh distribution under a progressive Type-II censoring scheme. We also provide unbiased estimators of the location parameter and scale parameter which have a nuisance parameter, and an estimator based on a pivotal quantity which does not depend on the other parameter. The proposed weighted least square estimator (WLSE) of the location parameter is not dependent on the scale parameter. In addition, the WLSE of the scale parameter is not dependent on the location parameter. The results are compared with the maximum likelihood method and pivot-based estimation method. The assessments and comparisons are done using Monte Carlo simulations and real data analysis. The simulation results show that the estimators ${\hat{\mu}}_u({\hat{\theta}}_p)$ and ${\hat{\theta}}_p({\hat{\mu}}_u)$ are superior to the other estimators in terms of the mean squared error (MSE) and bias.

Some Lower Bound of Cramer-Rao type for Median-Unbiased Estimates

  • So, Beong-Soo
    • Journal of Korean Society for Quality Management
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    • v.22 no.1
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    • pp.205-213
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    • 1994
  • We construct a new lower bound of Cramer-Rao type for the median-unbiased estimator in the presence a nuisance parameter. We also identify useful necessary and sufficient conditions for the attainability of the lower bound. Some applications including the analysis of censored reliability data are considered as examples.

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