• Title/Summary/Keyword: Categorical

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Bayesian Analysis for Categorical Data with Missing Traits Under a Multivariate Threshold Animal Model (다형질 Threshold 개체모형에서 Missing 기록을 포함한 이산형 자료에 대한 Bayesian 분석)

  • Lee, Deuk-Hwan
    • Journal of Animal Science and Technology
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    • v.44 no.2
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    • pp.151-164
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    • 2002
  • Genetic variance and covariance components of the linear traits and the ordered categorical traits, that are usually observed as dichotomous or polychotomous outcomes, were simultaneously estimated in a multivariate threshold animal model with concepts of arbitrary underlying liability scales with Bayesian inference via Gibbs sampling algorithms. A multivariate threshold animal model in this study can be allowed in any combination of missing traits with assuming correlation among the traits considered. Gibbs sampling algorithms as a hierarchical Bayesian inference were used to get reliable point estimates to which marginal posterior means of parameters were assumed. Main point of this study is that the underlying values for the observations on the categorical traits sampled at previous round of iteration and the observations on the continuous traits can be considered to sample the underlying values for categorical data and continuous data with missing at current cycle (see appendix). This study also showed that the underlying variables for missing categorical data should be generated with taking into account for the correlated traits to satisfy the fully conditional posterior distributions of parameters although some of papers (Wang et al., 1997; VanTassell et al., 1998) presented that only the residual effects of missing traits were generated in same situation. In present study, Gibbs samplers for making the fully Bayesian inferences for unknown parameters of interests are played rolls with methodologies to enable the any combinations of the linear and categorical traits with missing observations. Moreover, two kinds of constraints to guarantee identifiability for the arbitrary underlying variables are shown with keeping the fully conditional posterior distributions of those parameters. Numerical example for a threshold animal model included the maternal and permanent environmental effects on a multiple ordered categorical trait as calving ease, a binary trait as non-return rate, and the other normally distributed trait, birth weight, is provided with simulation study.

Computing Algorithm for Genetic Evaluations on Several Linear and Categorical Traits in A Multivariate Threshold Animal Model (범주형 자료를 포함한 다형질 임계개체모형에서 유전능력 추정 알고리즘)

  • Lee, D.H.
    • Journal of Animal Science and Technology
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    • v.46 no.2
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    • pp.137-144
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    • 2004
  • Algorithms for estimating breeding values on several categorical data by using latent variables with threshold conception were developed and showed. Thresholds on each categorical trait were estimated by Newton’s method via gradients and Hessian matrix. This algorithm was developed by way of expansion of bivariate analysis provided by Quaas(2001). Breeding values on latent variables of categorical traits and observations on linear traits were estimated by preconditioned conjugate gradient(PCG) method, which was known having a property of fast convergence. Example was shown by simulated data with two linear traits and a categorical trait with four categories(CE=calving ease) and a dichotomous trait(SB=Still Birth) in threshold animal mixed model(TAMM). Breeding value estimates in TAMM were compared to those in linear animal mixed model (LAMM). As results, correlation estimates of breeding values to parameters were 0.91${\sim}$0.92 on CE and 0.87${\sim}$0.89 on SB in TAMM and 0.72~0.84 on CE and 0.59~0.70 on SB in LAMM. As conclusion, PCG method for estimating breeding values on several categorical traits with linear traits were feasible in TAMM.

Investigation of Biases for Variance Components on Multiple Traits with Varying Number of Categories in Threshold Models Using Bayesian Inferences

  • Lee, D.H.
    • Asian-Australasian Journal of Animal Sciences
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    • v.15 no.7
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    • pp.925-931
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    • 2002
  • Gibbs sampling algorithms were implemented to the multi-trait threshold animal models with any combinations of multiple binary, ordered categorical, and linear traits and investigate the amount of bias on these models with two kinds of parameterization and algorithms for generating underlying liabilities. Statistical models which included additive genetic and residual effects as random and contemporary group effects as fixed were considered on the models using simulated data. The fully conditional posterior means of heritabilities and genetic (residual) correlations were calculated from 1,000 samples retained every 10th samples after 15,000 samples discarded as "burn-in" period. Under the models considered, several combinations of three traits with binary, multiple ordered categories, and continuous were analyzed. Five replicates were carried out. Estimates for heritabilities and genetic (residual) correlations as the posterior means were unbiased when underlying liabilities for a categorical trait were generated given by underlying liabilities of the other traits and threshold estimates were rescaled. Otherwise, when parameterizing threshold of zero and residual variance of one for binary traits, heritability estimates were inflated 7-10% upward. Genetic correlation estimates were biased upward if positively correlated and downward if negatively correlated when underling liabilities were generated without accounting for correlated traits on prior information. Residual correlation estimates were, consequently, much biased downward if positively correlated and upward if negatively correlated in that case. The more categorical trait had categories, the better mixing rate was shown.

A Study on Life-Cycle Categorical Variables of Quasi-Market SOC Public Enterprise (공기업 수명주기 분류변수 도출을 위한 기초연구 : 준시장형 SOC 공기업을 대상으로)

  • Park, Dong Sun;Shin, Wan Seon
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.37 no.4
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    • pp.168-176
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    • 2014
  • The enterprise life cycle derived from the product life cycle consists of introduction, growth, maturity and decline. The enterprise tries to reach the growth stage early and stay at the maturity stage stably through expanding its businesses and investing for the new technology. The public enterprise is not different but its life cycle is more prone to be affected by the national development and policy. A typical example can be found in the case of the quasi market SOC public enterprise which spends massive amount of fund to provide social infrastructure. After the fulfillment of its mandated mission it is exposed to the pressure of a merger or a closure usually because large portion of the debt is directly linked to the national financial stability and credit ratings. This research is focused on the variables that influence the life cycle of the quasi market SOC public Enterprise for its future competitiveness is in connection with its normalization, advancement and rationalization. In this respect, categorical variables system centering on public characteristics and profitability drew eight categorical variables such as policy outcomes, public benefit, finance and business values etc.

Imputation for Binary or Ordered Categorical Traits Based on the Bayesian Threshold Model (베이지안 분계점 모형에 의한 순서 범주형 변수의 대체)

  • Lee Seung-Chun
    • The Korean Journal of Applied Statistics
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    • v.18 no.3
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    • pp.597-606
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    • 2005
  • The nonresponse in sample survey causes a problem when it comes time to analyze dataset in public-use files where the user has only complete-data methods available and has limited information about the reasons for nonresponse. Recently imputation for nonresponse is becoming a standard approach for handling nonresponse and various imputation methods have been devised . However, most imputation methods concern with continuous traits while many interesting features are measured by binary or ordered categorical scales in sample survey. In this note. an imputation method for ignorable nonresponse in binary or ordered categorical traits is considered.

Multi-dimension Categorical Data with Bayesian Network (베이지안 네트워크를 이용한 다차원 범주형 분석)

  • Kim, Yong-Chul
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.11 no.2
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    • pp.169-174
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    • 2018
  • In general, the methods of the analysis of variance(ANOVA) for the continuous data and the chi-square test for the discrete data are used for statistical analysis of the effect and the association. In multidimensional data, analysis of hierarchical structure is required and statistical linear model is adopted. The structure of the linear model requires the normality of the data. A multidimensional categorical data analysis methods are used for causal relations, interactions, and correlation analysis. In this paper, Bayesian network model using probability distribution is proposed to reduce analysis procedure and analyze interactions and causal relationships in categorical data analysis.

The Connectedness between Categorical Policy Uncertainty Indexes and Volatility Index in Korea, Japan and the US (한국, 일본, 미국의 정책별 불확실성 지수와 변동성지수 간의 연계성)

  • Hangyong Lee; Sea-Gan Oh
    • Asia-Pacific Journal of Business
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    • v.14 no.4
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    • pp.319-330
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    • 2023
  • Purpose - The purpose of this paper is to examine the connectedness between categorical economic policy uncertainty (monetary, fiscal, trade and foreign exchange policy uncertainty) indexes and option-implied volatility index in Korea, Japan and the US. Design/methodology/approach - This paper employs the Diebold-Ylmaz (2012) model based on a VAR and generalized forecast error variance decomposition. This paper also conducts regression analyses to investigate whether the volatility indexes are explained by categorical policy uncertainty indexes. Findings - First, we find the total connectedness is stronger in Korea and Japan relative to the US. Second, monetary, fiscal, and foreign exchange policy uncertainty indexes are connected to each other but trade policy uncertainty index is not. Third, the volatility index in Japan and the US is mainly associated with monetary policy uncertainty while the volatility index in Korea is explained by fiscal policy uncertainty index. Research implications or Originality - To our knowledge, this is the first study to investigate the connectedness among categorical policy uncertainty indexes and the volatility index in Korea, Japan, and the US. The empirical results on the connectedness suggest that transparent policy and communication with the market in one type of policy would reduce the uncertainty in other policies.

Integration of Categorical Data using Multivariate Kriging for Spatial Interpolation of Ground Survey Data (현장 조사 자료의 공간 보간을 위한 다변량 크리깅을 이용한 범주형 자료의 통합)

  • Park, No-Wook
    • Spatial Information Research
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    • v.19 no.4
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    • pp.81-89
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    • 2011
  • This paper presents a multivariate kriging algorithm that integrates categorical data as secondary data for spatial interpolation of sparsely sampled ground survey data. Instead of using constant mean values in each attribute of categorical data, disaggregated local mean values at target grid points are first estimated by area-to-point kriging and then are used as local mean values in simple kriging with local means. This algorithm is illustrated through a case study of spatial interpolation of a geochemical copper element with geological map data. Cross validation results indicates that the presented algorithm leads to significant respective improvement of 15% and 25% in prediction capability, compared with univariate ordinary kriging and conventional simple kriging with constant mean values. It is expected that the multivariate kriging algorithm applied in this study would be effectively applied for spatial interpolation with categorical data.

The influence of brand benefit on the brand extension : focused on trademark belief and categorical similarity (소비자의 브랜드편익이 브랜드 확장에 미치는 영향 - 상표신념의 매개효과와 범주적 유사성의 조절효과를 중심으로 -)

  • Lee, Suntaek;Kim, Gwi-Gon
    • Journal of Digital Convergence
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    • v.16 no.4
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    • pp.127-135
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    • 2018
  • This study is to investigate the influence of brand benefit on brand extension, especially focusing on the mediating effect of trademark belief and the moderating effect of categorical similarity. This study restates that brand benefit affect consumers' brand extension attitude and confirms that it is completely mediated by trademark belief. In addition, this study finds that categorical similarity moderates the effects of brand benefit on brand extension attitude. The results of this study suggest a theoretical implication that trademark belief can be used as one of the brand extension strategies and a practical implication that the brand communication strategy based on brand benefits should be changed with the categorical similarity.

Latent class model for mixed variables with applications to text data (혼합모드 잠재범주모형을 통한 텍스트 자료의 분석)

  • Shin, Hyun Soo;Seo, Byungtae
    • The Korean Journal of Applied Statistics
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    • v.32 no.6
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    • pp.837-849
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    • 2019
  • Latent class models (LCM) are useful tools to draw hidden information from categorical data. This model can also be interpreted as a mixture model with multinomial component distributions. In some cases, however, an available dataset may contain both categorical and count or continuous data. For such cases, we can extend the LCM to a mixture model with both multinomial and other component distributions such as normal and Poisson distributions. In this paper, we consider a LCM for the data containing categorical and count data to analyze the Drug Review dataset which contains categorical responses and text review. From this data analysis, we show that we can obtain more specific hidden inforamtion than those from the LCM only with categorical responses.