• 제목/요약/키워드: Weighted average

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가중평균에 의한 역계산 어류 성장식추정법 개선 연구 (The study on the improvement of estimating back-calculated fish growth equation by weighted average method)

  • 양우성;이재봉;허요원;권대현;최석관;정상덕;안두해
    • 수산해양기술연구
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    • 제53권4호
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    • pp.471-475
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    • 2017
  • This study aims to suggest the methodology to improve to estimate back-calculated fish growth parameters using weighted average. It is to contribute to correct errors in the calculation of back-calculated growth equation with unequal numbers of sample by age. If the numbers of sample were evenly collected by age, each back-calculated length at age was equal between arithmetic and weighted averages. However, most samples cannot be evenly collected by age in reality because of different catchability by fishing gear and limitation of environment condition. Therefore, the estimation of back-calculated length by weighted average method is essential to calculate growth parameters. There were some published growth equations from back-calculated length using a simple arithmetic average with different numbers of samples by age when searching for back-calculated growth equations from 91 relevant papers. In this study, the process of deriving growth equation was investigated and two different average calculations were applied to a fish growth equation, for example of Acheilognathus signifer. Growth parameters, such as $L_{\infty}$, k and $t_0$, were estimated from two different back-calculated averages and the growth equations were compared with growth performance index. Based on the correction of back-calculated length using weighted average by age, the changes by female and male were -14.19% and -5.23% for $L_{\infty}$, and 59.28% and 18.91% for k, respectively. The corrected growth performance index by weighted average improved at 7.05% and 2.46% by female and male, respectively, compared to the arithmetic averages.

THE ALMOST SURE CONVERGENCE OF WEIGHTED AVERAGES UNDER NEGATIVE QUADRANT DEPENDENCE

  • Ryu, Dae-Hee
    • Journal of applied mathematics & informatics
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    • 제27권3_4호
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    • pp.885-893
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    • 2009
  • In this paper we study the strong law of large numbers for weighted average of pairwise negatively quadrant dependent random variables. This result extends that of Jamison et al.(Convergence of weight averages of independent random variables Z. Wahrsch. Verw Gebiete(1965) 4 40-44) to the negative quadrant dependence.

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A WEIGHTED EULER METHOD FOR SOLVING STIFF INITIAL VALUE PROBLEMS

  • BEONG IN, YUN
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • 제26권4호
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    • pp.353-361
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    • 2022
  • For an initial value problem, using a weighted average between two adjacent approximates, we propose a simple one-step method based on the Euler method. This method is useful for solving stiff initial value problem, even when the step size is not very small. Moreover, it can be seen that the proposed method with some selected weights results in improved approximation errors.

Monitoring social networks based on transformation into categorical data

  • Lee, Joo Weon;Lee, Jaeheon
    • Communications for Statistical Applications and Methods
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    • 제29권4호
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    • pp.487-498
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    • 2022
  • Social network analysis (SNA) techniques have recently been developed to monitor and detect abnormal behaviors in social networks. As a useful tool for process monitoring, control charts are also useful for network monitoring. In this paper, the degree and closeness centrality measures, in which each has global and local perspectives, respectively, are applied to an exponentially weighted moving average (EWMA) chart and a multinomial cumulative sum (CUSUM) chart for monitoring undirected weighted networks. In general, EWMA charts monitor only one variable in a single chart, whereas multinomial CUSUM charts can monitor a categorical variable, in which several variables are transformed through classification rules, in a single chart. To monitor both degree centrality and closeness centrality simultaneously, we categorize them based on the average of each measure and then apply to the multinomial CUSUM chart. In this case, the global and local attributes of the network can be monitored simultaneously with a single chart. We also evaluate the performance of the proposed procedure through a simulation study.

가중이동평균법을 이용한 케이블TV 광고시장에 대한 예측모형 개발 (A Study on Forecasting Model based Weighted Moving Average for Cable TV Advertising Market)

  • 조재형;김호영
    • 한국정보시스템학회지:정보시스템연구
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    • 제25권2호
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    • pp.153-171
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    • 2016
  • Purpose This study suggests the development of forecasting model for local cable TV advertisement. In order to verify the expected effect of the suggestion, using the causal loop map of System Dynamics, the factors affecting the prospects of cable TV commercial market were divided into 5 groups. Then targeting 97 people involved in the cable TV commercial market in Busan, Ulsan, and Gyeongnam, a survey was conducted on their perception of the current status of local advertisement market and future prospect. Design/methodology/approach The analysis of the collected data shows that workers in advertising and advertisers perceive the influence of cable TV as an advertising media to be high, while clearly understanding the problems of cable TV commercial market. Based on this the effects on the prospects of cable TV commercial market were analyzed and a forecasting method called Weighted Moving Average was applied. In order to improve accuracy of the added value of Weighted Moving Average, the 5 factors were divided into qualitative factors and quantitative factors, and using Multi-attribute Decision Making method, all the factors were normalized and weighting factors were deduced. The result of simulating the prospects of cable TV commercial market using Weighted Moving Average, both qualitative and quantitative factors showed downward turn in the market prospect for the following 10 years. Findings The result reflects generally negative perception of advertisement viewers about the prospects of cable TV commercial market. Compared to the previous studies on domestic cable TV commercials that focused on policy suggestions and surveys on perception of current status, this study has its significance in that it used scientific method and simulation for verification.

Exponentially Weighted Moving Average Control Charts for Dispersion Matrix

  • Chang, Duk-Joon;Shin, Jae-Kyoung
    • Journal of the Korean Data and Information Science Society
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    • 제15권3호
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    • pp.633-644
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    • 2004
  • Exponentially Weighted Moving Average(EWMA) control chart for variance-covariance matrix of several quality characteristics based on accumulate-combine approach has proposed. Numerical computations show that multivariate EWMA chart based on accumulate-combine approach is more efficient than corresponding multivariate EWMA chart based on combine-accumulate approach.

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퍼지 소속도 함수와 가중치 평균을 이용한 지도 학습 기반 분류기 설계 (Design of a Classifier Based on Supervised Learning Using Fuzzy Membership Function and Weighted Average)

  • 우영운
    • 한국정보통신학회논문지
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    • 제25권4호
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    • pp.508-514
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    • 2021
  • 본 논문에서는 지도 학습 기반의 분류기 제안을 위해, 분류 데이터의 각 특징별 소속도를 결정하는 3가지 종류의 퍼지 소속도 함수를 제안하였다. 또한 각 특징별 소속도들의 평균값을 이용하여 분류 결과를 도출하는 과정에 사용되는 평균값 산출 기법을 단순 산술평균이 아닌 다양한 가중치를 활용한 가중치 평균을 이용함으로써 분류기 성능을 향상시킬 수 있는 가능성을 제시하였다. 제안한 기법들의 실험을 위해 Iris, Ecoli, Yeast의 3가지 표준 데이터 세트를 사용하였다. 실험 결과, 서로 다른 특성의 데이터 세트들에 대해서도 고르게 우수한 분류 성능이 얻어질 수 있음을 확인하였고, 기존에 발표된 다른 기법들에 의한 해당 데이터 세트들의 분류 성능과 비교했을 때, 퍼지 소속도 함수의 개선과 가중치 평균 기법의 개선을 통해 더욱 우수한 분류 성능이 가능함을 확인할 수 있었다.

CERTAIN WEIGHTED MEAN INEQUALITY

  • Kim, Namkwon
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • 제18권3호
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    • pp.279-282
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    • 2014
  • In this paper, we report a new sharp inequality of interpolation type in $\mathbb{R}^n$. This inequality is for controlling weighted average of a function via $L^n$ norm of the gradient of a function together with its' certain exponential norm.

바닥충격음 차단성능 평가방법의 상호비교 (Comparison of Rating Methods for the Floor Impact Sound Insulation Performance)

  • 김경우;최현중;양관섭;이승언
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2005년도 춘계학술대회논문집
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    • pp.291-294
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    • 2005
  • In this study, we compared and analyzed the floor impact sound insulation performance produced by the rating methods. The rating methods are using reversed A-weighting curve, A-weighted sound pressure levels and arithmetic average. On-site floor impact sound pressure levels of living room and room are measured. The results of this study are 1)the rating using reversed A-weighting curve for heavy-weight impact sound's standard deviation is lower than that of light-weight impact sound, 2)the number of rating using A-weighted sound pressure levels and arithmetic average is larger than that of using reversed A-weighting curve, and 3)the number of rating using reversed A-weighting curve mainly depends on impact sound pressure level of 63Hz in heavy-weight impact sound.

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