• Title/Summary/Keyword: AIC

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Simulation Study on Model Selection Based on AIC under Unbalanced Design in Linear Mixed Effect Models (불균형 자료에서 AIC를 이용한 선형혼합모형 선택법의 효율에 대한 모의실험 연구)

  • Lee, Yong-Hee
    • The Korean Journal of Applied Statistics
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    • v.23 no.6
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    • pp.1169-1178
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    • 2010
  • This article consider a performance model selection based on AIC under unbalanced deign in linear mixed effect models. Vaida and Balanchard (2005) proposed conditional AIC for model selection in linear mixed effect models when the prediction of random effects is of primary interest. Theoretical properties of cAIC and related criteria have been investigated by Liang et al. (2008) and Greven and Kneib (2010). However, all of the simulation studies were performed under a balanced design. Even though functional form of AIC remain same even under the unbalanced deign, it is worthwhile to investigate performance of AIC based model selection criteria under the unbalanced design. The simulation study in this article shows how unbalancedness affects model selection in linear mixed effect models.

Adaptive Step-size Algorithm for the AIC in the Space-time Coded DS-CDMA System (시공간부호화된 DS-CDMA 시스템에서 적응스텝크기 알고리듬을 적용한 간섭제거수신기)

  • Yi, Joo-Hyun;Lee, Jae-Hong
    • Proceedings of the IEEK Conference
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    • 2004.06a
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    • pp.265-268
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    • 2004
  • In this paper. we propose an adaptive step-size algorithm for the adaptive interference canceller (AIC) in the space-time trellis coded DS-CDMA system. In the AIC, the performance of the blind LMS algorithms that updates the tap-weight vector of the AIC is heavily dependent on the choice of step-size. To improve the performance of the fixed step-size AIC (FS-AIC), the regular adaptive step-size algorithm is extended in complex domain and applied to the joint AIC and ML decoder scheme. Simulation results show that the joint adaptive step-size AIC (AS-AIC) and ML decoder scheme using the proposed algorithm has boner performance than not only the conventional ML decoder but also the joint FS-AIC and ML decoder scheme without much increase of the decoding delay and complexity.

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A CONSISTENT AND BIAS CORRECTED EXTENSION OF AKAIKE'S INFORMATION CRITERION(AIC) : AICbc(k)

  • Kwon, Soon H.;Ueno, M.;Sugeno, M.
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • v.2 no.1
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    • pp.41-60
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    • 1998
  • This paper derives a consistent and bias corrected extension of Akaike's Information Criterion (AIC), $AIC_{bc}$, based on Kullback-Leibler information. This criterion has terms that penalize the overparametrization more strongly for small and large samples than that of AIC. The overfitting problem of the asymptotically efficient model selection criteria for small and large samples will be overcome. The $AIC_{bc}$ also provides a consistent model order selection. Thus, it is widely applicable to data with small and/or large sample sizes, and to cases where the number of free parameters is a relatively large fraction of the sample size. Relationships with other model selection criteria such as $AIC_c$ of Hurvich, CAICF of Bozdogan and etc. are discussed. Empirical performances of the $AIC_{bc}$ are studied and discussed in better model order choices of a linear regression model using a Monte Carlo experiment.

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A Study on the P Wave Arrival Time Determination Algorithm of Acoustic Emission (AE) Suitable for P Waves with Low Signal-to-Noise Ratios (낮은 신호 대 잡음비 특성을 지닌 탄성파 신호에 적합한 P파 도달시간 결정 알고리즘 연구)

  • Lee, K.S.;Kim, J.S.;Lee, C.S.;Yoon, C.H.;Choi, J.W.
    • Tunnel and Underground Space
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    • v.21 no.5
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    • pp.349-358
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    • 2011
  • This paper introduces a new P wave arrival time determination algorithm of acoustic emission (AE) suitable to identify P waves with low signal-to-noise ratio generated in rock masses around the high-level radioactive waste disposal repositories. The algorithms adopted for this paper were amplitude threshold picker, Akaike Information Criterion (AIC), two step AIC, and Hinkley criterion. The elastic waves were generated by Pencil Lead Break test on a granite sample, then mixed with white noise to make it difficult to distinguish P wave artificially. The results obtained from amplitude threshold picker, AIC, and Hinkley criterion produced relatively large error due to the low signal-to-noise ratio. On the other hand, two step AIC algorithm provided the correct results regardless of white noise so that the accuracy of source localization was more improved and could be satisfied with the error range.

Advanced Image Coding based on spacial domain prediction (공간 영역 예측에 의한 정지 영상 부호화)

  • Cho, Sang-Gyu;Moon, Joon;Hwang, Jae-Jeong
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • v.9 no.1
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    • pp.425-428
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    • 2005
  • This paper is made up Advanced Image Coding(AIC) that combines algorithms from next generation image coding standard, H.264/MPEG-4 Part 10 advanced video coding(AVC) and still image compression standard, JPEG(Joint Photographic Experts Group). AIC combines intra frame block prediction from H.264 with a JPEG style discrete cosine transform and quantization, followed by Context-based Adaptive Binary Arithmetic Coding(CABAC) as used in H.264. In this paper, we analyzes the efficiency of the AIC algorithm and JPEG and JPEG-2000, and it presents of result.

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Using the corrected Akaike's information criterion for model selection (모형 선택에서의 수정된 AIC 사용에 대하여)

  • Song, Eunjung;Won, Sungho;Lee, Woojoo
    • The Korean Journal of Applied Statistics
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    • v.30 no.1
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    • pp.119-133
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    • 2017
  • Corrected Akaike's information criterion (AICc) is known to have better finite sample properties. However, Akaike's information criterion (AIC) is still widely used to select an optimal prediction model among several candidate models due to of a lack of research on benefits obtained using AICc. In this paper, we compare the performance of AIC and AICc through numerical simulations and confirm the advantage of using AICc. In addition, we also consider the performance of quasi Akaike's information criterion (QAIC) and the corrected quasi Akaike's information criterion (QAICc) for binomial and Poisson data under overdispersion phenomenon.

Comparisons of AIC and MDL on Estimation Reliability of Number of Soureces in Direction Finding Problem (Direction Finding Problem에서의 신호원 갯수 추정 신뢰도에 관한 AIC와 MDL의 비교)

  • 이일근
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.15 no.10
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    • pp.842-849
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    • 1990
  • In this paper, a couple of well-known methods for determination of the number of source signals impinging on sersor array in array processing are introduced and compared in terms of estimation accuracy. The one is the procedure issued by Akaike(Akaike's Information Criterion : AIC) and the other one by Schwartz and Rissanen(Minimum Description Length:MDL). This paper demonstrates, through computer simulation, that the AIC is more reliable than the MDL in such troublesome cases as very closely spaced source signlas, very limited number of sensors in the array, finite data sequences and/or low Signal-to-Noise ratio(S/N).

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AIC & MDL Algorithm Based on Beamspace, for Efficient Estimation of the Number of Signals (효율적인 신호개수 추정을 위한 빔공간 기반 AIC 및 MDL 알고리즘)

  • Park, Heui-Seon;Hwang, Suk-Seung
    • The Journal of the Korea institute of electronic communication sciences
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    • v.16 no.4
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    • pp.617-624
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    • 2021
  • The accurate estimation of the number of signals included in the received signal is required for the AOA(: Angle-of-Arrival) estimation, the interference suppression, the signal reception, etc. AIC(: Akaike Information Criterion) and MDL(: Minimum Description Length) algorithms, which are known as the typical algorithms to estimate the signal number, estimate the number of signals according to the minimum of each criterion. As the number of antenna elements increased, the estimation performance is enhanced, but the computational complexity is increased because values of criteria for entire antenna elements should be calculated for finding their minimum. In order to improve this problem, in this paper, we propose AIC and MDL algorithms based on the beamspace, which efficiently estimate the number of signals while reducing the computational complexity by reducing the dimension of an array antenna through the beamspace processing. In addition, we provide computer simulation results based on various scenarios for evaluating and analysing the estimation performance of the proposed algorithms.

Development of Control Algorithms Considering the Effect of a Control Sampling Period on the Total Amount of Switching for a Switched System (컨트롤 샘플링 주기가 스위칭 시스템의 결합-분리 횟수에 미치는 영향을 고려한 제어 알고리듬 개발)

  • Joung, Jin-Wook;Chung, Lan
    • Journal of the Earthquake Engineering Society of Korea
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    • v.13 no.4
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    • pp.67-76
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    • 2009
  • Recently, the active interaction control (AIC) system was proposed as a semi-active control system. The AIC system consists of a primary structure and an auxiliary structure. The objective of the AIC system is to control the response of the primary structure through engagement and disengagement between the primary and auxiliary structures. Previous switching control algorithms have been shown to be effective in reducing the response of the primary structure. However, they have the main drawback of requiring an excessive engagement-disengagement frequency and high interaction force. In this paper, the regions in which the switching is activated and the regions in which the switching is deactivated are described separately, to effectively determine the engagement or the disengagement. The general relationship between the switching regions and the deactivated switching regions selected according to the engagement-disengagement conditions is described within the newly-developed comprehensive switching framework. The proposed engagement-disengagement conditions are designed within a comprehensive switching framework, to reduce engagement-disengagement frequency and interaction force. Furthermore, the effect of a control sampling period on the AIC system is explained in terms of the engagement-disengagement frequency. The effectiveness of the proposed algorithms and the effect of the control sampling period are considered for a single degree of freedom model under free vibration. It is observed that increasing the duration of stay by using a large control sampling period prevents the AIC system from activating the possible chance of switching. The proposed algorithms are shown to be effective, both in restricting ineffective switching and in reducing interaction force.