• Title/Summary/Keyword: Logistic

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A Study on Change of Logistics in the region of Seoul, Incheon, Kyunggi (물류예측모형에 관한 연구 -수도권 물동량 예측을 중심으로-)

  • Roh Kyung-Ho
    • Management & Information Systems Review
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    • v.7
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    • pp.427-450
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    • 2001
  • This research suggests the estimation methodology of Logistics. This paper elucidates the main problems associated with estimation in the regression model. We review the methods for estimating the parameters in the model and introduce a modified procedure in which all models are fitted and combined to construct a combination of estimates. The resulting estimators are found to be as efficient as the maximum likelihood (ML) estimators in various cases. Our method requires more computations but has an advantage for large data sets. Also, it enables to detect particular features in the data structure. Examples of real data are used to illustrate the properties of the estimators. The backgrounds of estimation of logistic regression model is the increasing logistic environment importance today. In the first phase, we conduct an exploratory study to discuss 9 independent variables. In the second phase, we try to find the fittest logistic regression model. In the third phase, we calculate the logistic estimation using logistic regression model. The parameters of logistic regression model were estimated using ordinary least squares regression. The standard assumptions of OLS estimation were tested. The calculated value of the F-statistics for the logistic regression model is significant at the 5% level. The logistic regression model also explains a significant amount of variance in the dependent variable. The parameter estimates of the logistic regression model with t-statistics in parentheses are presented in Table. The object of this paper is to find the best logistic regression model to estimate the comparative accurate logistics.

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The uniform laws of large numbers for the chaotic logistic map

  • Bae, Jongsig;Hwang, Changha;Jun, Doobae
    • Journal of the Korean Data and Information Science Society
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    • v.28 no.6
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    • pp.1565-1571
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    • 2017
  • The standard logistic map is an iterative function, which forms a discrete-time dynamic system. The chaotic logistic map is a kind of ergodic map defined over the unit interval. In this paper we study the limiting behaviors on the several processes induced by the chaotic logistic map. We derive the law of large numbers for the process induced by the chaotic logistic map. We also derive the uniform law of large numbers for this process. When deriving the uniform law of large numbers, we study the role of bracketing of the indexed class of functions associated with the process. Then we apply the idea of DeHardt (1971) associated with the bracketing method to the process induced by the logistic map. We finally illustrate an application to Monte Carlo integration.

Logistic Supportability Improvement Program for the Future Main Battle Tank (고장진단체계 구축을 통한 미래전차의 군수지원성 향상 방안 연구)

  • Jung, ChangMo;Lee, MyungChun
    • Journal of the Korean Society of Systems Engineering
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    • v.1 no.2
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    • pp.34-42
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    • 2005
  • Logistic Support Analysis(LSA) and Logistic Supportability Review must be carried out as soon as possible in development stage in order to minimize operation/maintenance cost that head the list of weapon cost and improve logistic supportability of the weapon system. And the result must be used for hardware designs to set up to be able to input to the system design and logistic support elements. Therefore Logistic Support Elements must be planed/developed/supplied with the main combat system concurrently and performance and logistic supportability of the comabat system had better be improved mutually. This report describes maintenance concept changes of weapon systems, fault diagnosis function and test equipment state on the domestic MBT(main battle tank). And then it presents application and intensification of itself fault diagnosis system for a domestic future MBT considering connection with IETM(Interactive Electronic Technical Manual) and TE(Test Equipment).

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Collapsibility and Suppression for Cumulative Logistic Model

  • Hong, Chong-Sun;Kim, Kil-Tae
    • Communications for Statistical Applications and Methods
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    • v.12 no.2
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    • pp.313-322
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    • 2005
  • In this paper, we discuss suppression for logistic regression model. Suppression for linear regression model was defined as the relationship among sums of squared for regression as well as correlation coefficients of. variables. Since it is not common to obtain simple correlation coefficient for binary response variable of logistic model, we consider cumulative logistic models with multinomial and ordinal response variables rather than usual logistic model. As number of category of a response variable for the cumulative logistic model gets collapsed into binary, it is found that suppressions for these logistic models are changed. These suppression results for cumulative logistic models are discussed and compared with those of linear model.

Improved Exact Inference in Logistic Regression Model

  • Kim, Donguk;Kim, Sooyeon
    • Communications for Statistical Applications and Methods
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    • v.10 no.2
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    • pp.277-289
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    • 2003
  • We propose modified exact inferential methods in logistic regression model. Exact conditional distribution in logistic regression model is often highly discrete, and ordinary exact inference in logistic regression is conservative, because of the discreteness of the distribution. For the exact inference in logistic regression model we utilize the modified P-value. The modified P-value can not exceed the ordinary P-value, so the test of size $\alpha$ based on the modified P-value is less conservative. The modified exact confidence interval maintains at least a fixed confidence level but tends to be much narrower. The approach inverts results of a test with a modified P-value utilizing the test statistic and table probabilities in logistic regression model.

The Study of the Influence of Induced Abortion on Secondary Infertility analyzed by Logistic Regression (Logistic Analysis를 이용하여 분석한 인공유산이 속발성불임에 미치는 영향)

  • Lee, Won-Chul
    • Journal of Preventive Medicine and Public Health
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    • v.15 no.1
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    • pp.179-186
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    • 1982
  • The methods controlling the confounding factors were discussed using the data of secondary infertility with induced abortion. Mantel-Haenszel method and logistic model were applied in the analysis to find out which factors were confounding and/or effect modification variables. In the logistic analysis, the main effect of induced abortion, spontaneous abortion, age and interaction effect between induced abortion and spontaneous abortion were chosen as independent variables being regressed into logistic functions. Spontaneons abortion was interpreted as a potential confounder and at the same time potential effect modifier and age was interpreted as potential confounder. Spontaneous abortion was shown to be more important influencing factor than age to the secondary infertility. In the course of logistic analysis, the problem of parameter estimation and hypothesis testing, assessing the fitness of a model, and selection of the best model were briefly explained. For the program of logistic model, FUNCAT Procedure of SAS package was chosen.

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On Logistic Regression Analysis Using Propensity Score Matching (성향점수매칭 방법을 사용한 로지스틱 회귀분석에 관한 연구)

  • Kim, So Youn;Baek, Jong Il
    • Journal of Applied Reliability
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    • v.16 no.4
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    • pp.323-330
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    • 2016
  • Purpose: Recently, propensity score matching method is used in a large number of research paper, nonetheless, there is no research using fitness test of before and after propensity score matching. Therefore, comparing fitness of before and after propensity score matching by logistic regression analysis using data from 'online survey of adolescent health' is the main significance of this research. Method: Data that has similar propensity in two groups is extracted by using propensity score matching then implement logistic regression analysis on before and after matching separately. Results: To test fitness of logistic regression analysis model, we use Model summary, -2Log Likelihood and Hosmer-Lomeshow methods. As a result, it is confirmed that the data after matching is more suitable for logistic regression analysis than data before matching. Conclusion: Therefore, better result which has appropriate fitness will be shown by using propensity score matching shows better result which has better fitness.

Cohort Analysis of Incidence/Mortality of Liver Cancer in Japan through Logistic Curve Fitting

  • Okamoto, Etsuji
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.10
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    • pp.5891-5893
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    • 2013
  • Incidence/mortality of liver cancer follow logistic curves because there is a limit reflecting the prevalence of hepatitis virus carriers in the cohort. The author fitted logistic curves to incidence/mortality data covering the nine five-year cohorts born in 1911-1955 of both sexes. Goodness-of-fit of logistic curves was sufficiently precise to be used for future predictions. Younger cohorts born in 1936 or later were predicted to show constant decline in incidence/mortality in the future. The male cohort born in 1931-35 showed an elevated incidence/mortality of liver cancer early in their lives supporting the previous claim that this particular cohort had suffered massive HCV infection due to nation-wide drug abuse in the 1950s. Declining case-fatality observed in younger cohorts suggested improved treatment of liver cancer. This study demonstrated that incidence/mortality of liver cancer follow logistic curves and fitted logistic formulae can be used for future prediction. Given the predicted decline of incidence/mortality in younger cohorts, liver cancer is likely to be lost to history in the not-so-distant future.

MULTIPLE OUTLIER DETECTION IN LOGISTIC REGRESSION BY USING INFLUENCE MATRIX

  • Lee, Gwi-Hyun;Park, Sung-Hyun
    • Journal of the Korean Statistical Society
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    • v.36 no.4
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    • pp.457-469
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    • 2007
  • Many procedures are available to identify a single outlier or an isolated influential point in linear regression and logistic regression. But the detection of influential points or multiple outliers is more difficult, owing to masking and swamping problems. The multiple outlier detection methods for logistic regression have not been studied from the points of direct procedure yet. In this paper we consider the direct methods for logistic regression by extending the $Pe\tilde{n}a$ and Yohai (1995) influence matrix algorithm. We define the influence matrix in logistic regression by using Cook's distance in logistic regression, and test multiple outliers by using the mean shift model. To show accuracy of the proposed multiple outlier detection algorithm, we simulate artificial data including multiple outliers with masking and swamping.

Logistic Model for Normality by Neural Networks

  • Lee, Jea-Young;Rhee, Seong-Won
    • Journal of the Korean Data and Information Science Society
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    • v.14 no.1
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    • pp.119-129
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    • 2003
  • We propose a new logistic regression model of normality curves for normal(diseased) and abnormal(nondiseased) classifications by neural networks in data mining. The fitted logistic regression lines are estimated, interpreted and plotted by the neural network technique. A few goodness-of-fit test statistics for normality are discussed and the performances by the fitted logistic regression lines are conducted.

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