• 한국조사연구학회지:조사연구
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• 제2권1호
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• pp.73-86
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• 2001

본 논문은 복합표본조사 분석에서 회귀모형 접근법으로 사용되는 모형 기반 접근법, 설계 기반 접근법과 일반화 추정 방정식 접근법을 설명하고, 이들을 실증적으로 비교한 것이다. 또한 설계 기반 접근법과 일반화 추정 방정식 접근법에 대해서 설계효과와 가중치 효과 분석을 통해서 표본 설계가 모수 추정에 미치는 영향을 살펴보았다.

• Water Engineering Research
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• 제5권4호
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• pp.185-193
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• 2004

Estimates of annual actual evapotranspiration are needed in water balance studies, water resources management projects, and many different types of hydrologic studies. This study validated a set of 5 empirical equations of estimating annual actual evapotranspiration with climate data on 11 watersheds, and evaluated the further applicability of these forms in estimating annual runoff on watershed level. Five empirical equations generally overestimated annual evapotranspiration, with relative errors ranging $3.3\%$ to $47.2\%$. The results show that Schreiber formula can be applicable in determining annual evapotranspiration in sub-humid region that is classified by aridity index, while Zhang equation gave better results than the remaining methods in humid region. The mean differences for annual evapotranspiration bias over 11 watersheds are Zhang, Schreiber, Budyko, Pike, and Ol'dekop formula from lowest to highest. The empirical equations provide a practical tool to help water resources managers in estimating regional water resources on ungauged large watershed.

• 응용통계연구
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• 제9권2호
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• pp.83-94
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• 1996

윷의 확률에 대한 기하학적 접근의 선행연구가 있었고, 이 논문은 그 선행연구를 보완, 발전시키는데 목적을 두고 있다. 특히, 윷의 확률이 '논리적'으로 계산되기 어려운 상황과 그 이유를 설명하고, 통계학적인 추정방법들을 제시하고 있다. 시중에 판매되고 있는 여러가지 종류의 윷을 사용함으로써 실질적인 회귀선을 유도하였고, 이와 같이 추정된 확률을 통하여 도, 개, 걸, 윷, 모의 출현빈도순서 및 예상확률을 구할 수 있게 되었다. 이러한 통계학적인 접근의 결과는 기초확률시간이나 기초통계학 시간에 활용될 수 있을 것이다.

• International Journal of Internet, Broadcasting and Communication
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• 제9권1호
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• pp.9-17
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• 2017

This paper describes a process of developing commercial real time image recognition system with company. In this paper we will make a system that is combining an empirical kernel map method and conjugate least squares support vector machine in order to represent images in a low-dimensional subspace for real time image recognition. In the traditional approach calculating these eigenspace models, known as traditional PCA method, model must capture all the images needed to build the internal representation. Updating of the existing eigenspace is only possible when all the images must be kept in order to update the eigenspace, requiring a lot of storage capability. Proposed method allows discarding the acquired images immediately after the update. By experimental results we can show that empirical kernel map has similar accuracy compare to traditional batch way eigenspace method and more efficient in memory requirement than traditional one. This experimental result shows that proposed model is suitable for commercial real time image recognition system.

• 품질경영학회지
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• 제37권4호
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• pp.31-42
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• 2009

Various studies have been undertaken in order to effectively understand customer requirements. Kano proposed a dualistic approach, physical fulfillment and customer satisfaction, to differentiate Attractive, Must-be, One-dimensional quality attributes. As there were a few limitations on the Kano's method, researchers have proposed improved methods. However, there have been few empirical evidences that the improved methods are superior to the original Kano's method for identifying relevant quality attributes. The objective of this study is to provide a comparative study on Kano and improved Kanomethods based on empirical analysis of quality attributes on University services. For the analysis of the questionnaire formats, the Kano's original 5 scale questionnaire is more effective than improved methods, direct and 3 scale questionnaire. For the analysis of evaluation methods, the original Kano and Timko's method using the evaluation table are more effective than quantifying methods, Domouchel and Lim's methods.

• Communications for Statistical Applications and Methods
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• 제30권4호
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• pp.355-368
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• 2023

This article introduces the R package ELCIC (https://cran.r-project.org/web/packages/ELCIC/index.html), which provides an empirical likelihood-based information criterion (ELCIC) for model selection that includes, but is not limited to, variable selection. The empirical likelihood is a semi-parametric approach to draw statistical inference that does not require distribution assumptions for data generation. Therefore, ELCIC is more robust and versatile in the context of model selection compared to the currently existing information criteria. This paper illustrates several applications of ELCIC, including its use in generalized linear models, generalized estimating equations (GEE) for longitudinal data, and weighted GEE (WGEE) for missing longitudinal data under the mechanisms of missing at random and dropout.

• The Journal of Asian Finance, Economics and Business
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• 제7권2호
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• pp.143-149
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• 2020

Low inflation and sustainable growth have been the major macroeconomic goals being pursued by every developing country, Vietnam inclusive. The effect of inflation on economic growth has been intensively analyzed by a variety of studies, but the empirical evidence more often than not remains controversial and ambiguous. One common hypothesis of previous studies is that they have assumed that the effect of inflation on growth is symmetric. The main purpose of this study is to investigate the asymmetric effect of inflation and money supply on economic growth using the Nonlinear Autoregressive Distributed Lag approach introduced by Shin, Byungchul, and Greenwood-nimmo (2013) for Vietnam over the period 1990-2017. Empirical results provide evidence that the effects of inflation on economic growth are negative and asymmetric in the long run. The impact of money supply on growth is positive in both the short-run and long-run. Accordingly, the impact of the increase in the inflation rate is bigger than the decreasing in the long-run. This different impact is significant and high inflation will destruct economic activities. As a result, the study provides empirical evidence for the authorities to plan monetary policies and control the rate of inflation to achieve sustainable economic development in the long-run.

• 한국항해항만학회지
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• 제27권2호
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• pp.163-170
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• 2003

본 연구는 한중정기항로에서 국적선사 활성화 방안에 관한 실증연구이다. 본 연구를 위하여 한중항로의 국적정기선사, 중국적 정기선사, 3국적 정기선사 등의 종사자에 실문지 500매를 배포하여 290매 회수하였으며, 한중정기항로 국적선사 활성화 요인과 물동량 증대효과의 관련성을 검증하기 위하여 먼저, 설문문항의 신뢰성(Reliability)은 크론바하 알파(Cronbach's Alpha)에 의한 내적 일관성 검사법을 통하여 검정하였고, 독립변수의 구성타당성(Construct Validity)을 검정하기 위해서 변수들이 선형결합이라는 가정 하에 요인을 추출하는 주성분 법(Principal Components)을 이용한 요인분석(Factor Analysis)을 실시하였다. 그리고 연구가설을 검증하기 위하여 다변량 회귀분석(Multiple Regression Analysis)을 실시하였다.

• Wind and Structures
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• 제10권5호
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• pp.401-420
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• 2007

Field measurements of the wind-induced response of two residential reinforced concrete buildings, among the tallest in the world, have been performed during two typhoons. Natural periods and damping values have been determined and compared with other field measurements and empirical predictors. Suitable and common empirical predictors of natural period and structural damping have been obtained that describe the trend of tall, reinforced concrete buildings whose structural vibrations have been measured in the collection of studies in Hong Kong compiled by the authors. This data is especially important as the amount of information known about the dynamic parameters of buildings of these heights is limited. Effects of the variation of the natural period and damping values on the alongwind response of a tall building for serviceability-level wind conditions have been profiled using the gust response factor approach. When using this approach on these two buildings, the often overestimated natural periods and structural damping values suggested by empirical predictors tended to offset each other. Gust response factors calculated using the natural periods and structural damping values measured in the field were smaller than if calculated using design-stage values.

• Structural Engineering and Mechanics
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• 제77권3호
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• pp.355-368
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• 2021

The time-varying mean (TVM) component of non-stationary wind speeds is commonly extracted utilizing empirical mode decomposition (EMD) in practice, whereas the accuracy of the extracted TVM is difficult to be quantified. To deal with this problem, this paper proposes an approach to identify and extract the optimal TVM from several TVM results obtained by the EMD. It is suggested that the optimal TVM of a 10-min time history of wind speeds should meet both the following conditions: (1) the probability density function (PDF) of fluctuating wind component agrees well with the modified Gaussian function (MGF). At this stage, a coefficient p is newly defined as an evaluation index to quantify the correlation between PDF and MGF. The smaller the p is, the better the derived TVM is; (2) the number of local maxima of obtained optimal TVM within a 10-min time interval is less than 6. The proposed approach is validated by a numerical example, and it is also adopted to extract the optimal TVM from the field measurement records of wind speeds collected during a sandstorm event.