• Title/Summary/Keyword: Auto-regressive

Search Result 249, Processing Time 0.022 seconds

Beyond Growth: Does Tourism Promote Human Development in India? Evidence from Time Series Analysis

  • SHARMA, Manu;MOHAPATRA, Geetilaxmi;GIRI, Arun Kumar
    • The Journal of Asian Finance, Economics and Business
    • /
    • v.7 no.12
    • /
    • pp.693-702
    • /
    • 2020
  • The present study aims to investigate the impact of tourism growth on human development in Indian economy. For this purpose, the study uses annual data from 1980 to 2018 and utilizes two proxies for tourism growth - tourism receipt and tourist arrivals - and uses human development index calculated by UNDP. The study uses control variables such as government expenditure and trade openness. The study employs auto regressive distributed lag (ARDL) approach to investigate the cointegrating relationship among the variables in the model. Further, the study also explores the causal nexus between tourism sector and human development by using the Toda-Yamamoto Granger non-causality test. The result of ARDL bounds test reveals the existence of cointegrating relationship between human development indicators, government expenditure, trade openness, and tourism sector growth. The cointegating coefficient confirms a positive and significant relationship between tourism sector growth and human development in India. The causality result suggests that economic growth and tourism have a positive impact while trade openness has a negative impact on human development in India. The major findings of this study suggest that tourism plays an important role in the socio-economic development of Indian economy in recent years and the country must develop this sector to achieve sustainable development.

Electricity Price Forecasting in Ontario Electricity Market Using Wavelet Transform in Artificial Neural Network Based Model

  • Aggarwal, Sanjeev Kumar;Saini, Lalit Mohan;Kumar, Ashwani
    • International Journal of Control, Automation, and Systems
    • /
    • v.6 no.5
    • /
    • pp.639-650
    • /
    • 2008
  • Electricity price forecasting has become an integral part of power system operation and control. In this paper, a wavelet transform (WT) based neural network (NN) model to forecast price profile in a deregulated electricity market has been presented. The historical price data has been decomposed into wavelet domain constitutive sub series using WT and then combined with the other time domain variables to form the set of input variables for the proposed forecasting model. The behavior of the wavelet domain constitutive series has been studied based on statistical analysis. It has been observed that forecasting accuracy can be improved by the use of WT in a forecasting model. Multi-scale analysis from one to seven levels of decomposition has been performed and the empirical evidence suggests that accuracy improvement is highest at third level of decomposition. Forecasting performance of the proposed model has been compared with (i) a heuristic technique, (ii) a simulation model used by Ontario's Independent Electricity System Operator (IESO), (iii) a Multiple Linear Regression (MLR) model, (iv) NN model, (v) Auto Regressive Integrated Moving Average (ARIMA) model, (vi) Dynamic Regression (DR) model, and (vii) Transfer Function (TF) model. Forecasting results show that the performance of the proposed WT based NN model is satisfactory and it can be used by the participants to respond properly as it predicts price before closing of window for submission of initial bids.

Spectrum Usage Forecasting Model for Cognitive Radio Networks

  • Yang, Wei;Jing, Xiaojun;Huang, Hai
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.12 no.4
    • /
    • pp.1489-1503
    • /
    • 2018
  • Spectrum reuse has attracted much concern of researchers and scientists, however, the dynamic spectrum access is challenging, since an individual secondary user usually just has limited sensing abilities. One key insight is that spectrum usage forecasting among secondary users, this inspiration enables users to obtain more informed spectrum opportunities. Therefore, spectrum usage forecasting is vital to cognitive radio networks (CRNs). With this insight, a spectrum usage forecasting model for the occurrence of primary users prediction is derived in this paper. The proposed model is based on auto regressive enhanced primary user emergence reasoning (AR-PUER), which combines linear prediction and primary user emergence reasoning. Historical samples are selected to train the spectrum usage forecasting model in order to capture the current distinction pattern of primary users. The proposed scheme does not require the knowledge of signal or of noise power. To verify the performance of proposed spectrum usage forecasting model, we apply it to the data during the past two months, and then compare it with some other sensing techniques. The simulation results demonstrate that the spectrum usage forecasting model is effective and generates the most accurate prediction of primary users occasion in several cases.

Hybrid CSA optimization with seasonal RVR in traffic flow forecasting

  • Shen, Zhangguo;Wang, Wanliang;Shen, Qing;Li, Zechao
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.11 no.10
    • /
    • pp.4887-4907
    • /
    • 2017
  • Accurate traffic flow forecasting is critical to the development and implementation of city intelligent transportation systems. Therefore, it is one of the most important components in the research of urban traffic scheduling. However, traffic flow forecasting involves a rather complex nonlinear data pattern, particularly during workday peak periods, and a lot of research has shown that traffic flow data reveals a seasonal trend. This paper proposes a new traffic flow forecasting model that combines seasonal relevance vector regression with the hybrid chaotic simulated annealing method (SRVRCSA). Additionally, a numerical example of traffic flow data from The Transportation Data Research Laboratory is used to elucidate the forecasting performance of the proposed SRVRCSA model. The forecasting results indicate that the proposed model yields more accurate forecasting results than the seasonal auto regressive integrated moving average (SARIMA), the double seasonal Holt-Winters exponential smoothing (DSHWES), and the relevance vector regression with hybrid Chaotic Simulated Annealing method (RVRCSA) models. The forecasting performance of RVRCSA with different kernel functions is also studied.

A Bayesian approach for vibration-based long-term bridge monitoring to consider environmental and operational changes

  • Kim, Chul-Woo;Morita, Tomoaki;Oshima, Yoshinobu;Sugiura, Kunitomo
    • Smart Structures and Systems
    • /
    • v.15 no.2
    • /
    • pp.395-408
    • /
    • 2015
  • This study aims to propose a Bayesian approach to consider changes in temperature and vehicle weight as environmental and operational factors for vibration-based long-term bridge health monitoring. The Bayesian approach consists of three steps: step 1 is to identify damage-sensitive features from coefficients of the auto-regressive model utilizing bridge accelerations; step 2 is to perform a regression analysis of the damage-sensitive features to consider environmental and operational changes by means of the Bayesian regression; and step 3 is to make a decision on the bridge health condition based on residuals, differences between the observed and predicted damage-sensitive features, utilizing 95% confidence interval and the Bayesian hypothesis testing. Feasibility of the proposed approach is examined utilizing monitoring data on an in-service bridge recorded over a one-year period. Observations through the study demonstrated that the Bayesian regression considering environmental and operational changes led to more accurate results than that without considering environmental and operational changes. The Bayesian hypothesis testing utilizing data from the healthy bridge, the damage probability of the bridge was judged as no damage.

Modeling of Reaction Wheel Using KOMPSAT-1 Telemetry (KOMPSAT-1 Telemetry를 활용한 반작용휠 모델링)

  • Lee, Seon-Ho;Choi, Hong-Taek;Yong, Gi-Ryeok;Oh, Si-Hwan;Rhee, Seung-U
    • Journal of the Korean Society for Aeronautical & Space Sciences
    • /
    • v.32 no.3
    • /
    • pp.45-50
    • /
    • 2004
  • The design of reaction wheel control logic is critical to achieve the spacecraft attitude stabilization and performance requirements for the successful mission. Due to various uncertainties on orbit there exist limitation to obtain the model parameters through the ground tests and to design the associated control logic. Thus, the model parameter correction using on-orbit data is essential to the control performance on orbit. This paper performs the system identification using KOMPSAT-1 telemetry data and extracts the model parameters of the reaction wheel. Moreover, the reaction wheel is remodeled and compared with the ground test results.

A Study on the AR Identification of unknown system using Cumulant (Cumulant를 이용한 미지 시스템의 AR 식별에 관한 연구)

  • Lim, Seung-Gag
    • Journal of the Institute of Electronics Engineers of Korea TC
    • /
    • v.43 no.2 s.344
    • /
    • pp.39-43
    • /
    • 2006
  • This paper deals with the AR Identification of unknown system using cumulant, which is the 3rd order statistics of output signal in the presence of the noise signal. The algorithms for identification of unknown system we applies to the AR identification method using the cumulant which is possible to the guarantees of global convergence and the representation of amplitude and phase information of system among with the method of parametric modeling. In the process of identification, we considered unknown system to the one of AR system. After the generation of input signal, it was being passed through the system then We use the its output signal that the noise is added. As a result of identification of AR system by changing the signal to noise ratio, we get the fairly good results compared to original system output values and confirmed that the pole was located in the unit circle of z transform.

Temperature Classification of Heat-treated Metals using Pattern Recognition of Ultrasonic Signal (초음파 신호의 패턴 인식에 의한 금속의 열처리 온도 분류)

  • Im, Rae-Muk;Sin, Dong-Hwan;Kim, Deok-Yeong;Kim, Seong-Hwan
    • The Transactions of the Korean Institute of Electrical Engineers A
    • /
    • v.48 no.12
    • /
    • pp.1544-1553
    • /
    • 1999
  • Recently, ultrasonic testing techniques have been widely used in the evaluation of the quality of metal. In this experiment, six heat-treated temperature of specimen have been considered : 0, 1200, 1250, 1300, 1350 and 1387$^{\circ}C$. As heat-treated temperature increases, the grain size of stainless steel also increases and then, eventually make it destroy. In this paper, a pattern recognition method is proposed to identify the heat-treated temperature of metals by evidence accumulation based on artificial intelligence with multiple feature parameters; difference absolute mean value(DAMV), variance(VAR), mean frequency(MEANF), auto regressive model coefficient(ARC), linear cepstrum coefficient(LCC) and adaptive cepstrum vector(ACV). The grain signal pattern recognition is carried out through the evidence accumulation procedure using the distances measured with reference parameters. Especially ACV is superior to the other parameters. The results (96% successful pattern classification) are presented to support the feasibility of the suggested approach for ultrasonic grain signal pattern recognition.

  • PDF

국채선물을 이용한 채권포트폴리오의 VECM과 VAR모형에 의한 헤지

  • Han, Seong-Yun;Im, Byeong-Jin;Won, Jong-Hyeon
    • The Korean Journal of Financial Studies
    • /
    • v.8 no.1
    • /
    • pp.231-252
    • /
    • 2002
  • 2000년 7월부터 채권시가평가의 실행으로 채권운용자들도 채권포트폴리오의 위험을 채권선물을 이용하여 통제하거나 감소시키기 위해 헤지를 하여야 한다. 이때 헤지비율을 추정하는 방법으로는 전통적 회귀분석모형, 백터오차수정모형(Vector Error Correction Model : VECM)과 VAR모형(Vector AutoRegressive Model)이 있다. 전통적인 회귀분석모형에 의하여 추정된 헤지비율은 시계열자료의 불안정성(nonstationary) 등으로 인하여 잘못 추정될 가능성이 있어 면밀한 검토와 분석 후 사용하여야 한다. 시계열자료의 불안정성으로 말미암아 야기되는 문제점들을 개선할 수 있는 모형으로서 VECM과 VAR모형이 널리 이용되고 있다. 따라서 본 연구는 VECM과 VAR모형을 사용하여 추정된 헤지비율과 전통적 회귀분석모형을 사용하여 추정한 헤지비율을 비교하여 어떤 모형으로 추정한 헤지비율이 더 정확한지를 평가하는데 목적을 두고 있다. 즉, 본 연구는 KTB 현 선물의 헤징에 대한 연구로 2000년 1월 4일부터 2001년 7월 27일까지 385일간의 KTB 현 선물 자료와 불룸버그 국채지수를 대상으로 VECM 및 VAR모형과 전통적 회귀분석모형에 의한 헤지비율을 추정하고 각 모형의 설명력과 예측력을 비교하고자 한다. 이 연구의 실증분석 결과, KTB 현물가격과 KTB 선물가격간, 블룸버그 국채지수와 KTB 선물가격간에는 공적분 관계가 존재하며, VECM 및 VAR와 전통적 회귀분석모형을 이용하여 추정한 최적헤지비율의 크기는 대동소이(大同小異)하며, 전통적 회귀분석방법을 이용하는 것이 VECM과 VAR모형을 이용할 때 보다 설명력과 예측력이 우월한 것으로 나타났다.

  • PDF

A Chaos Characteristic Analysis of Nonlinear Rainfall-Runoff Data (비선형 강우-유출량 자료에 대한 카오스 특성 분석)

  • Park, Sung-Chun;Jin, Young-Hoon;Oh, Chang-Ryol
    • Proceedings of the Korea Water Resources Association Conference
    • /
    • 2005.05b
    • /
    • pp.614-618
    • /
    • 2005
  • 수문시계열 분석과 예측은 대부분 ARMA(AutoRegressive Moving Average) 형태의 선형적인 추계학적인 모형을 이용하였으나 자현현상이 복잡해지고 비선형적인 특성을 가짐에 따라 선형적인 해석은 수문시계열의 분석과 예측에 있어서 많은 오류를 내포하고 있다. 이와 같은 문제를 해결하기 위한 시도로 Chaos이론이란 개념이 사용되기 시작하였으며, 수자원분야에서는 1980년대 후반부터 물수지 방정식 및 강우유출에 대한 카오스적 특성분석 등 많은 연구가 진행되었다. 본 연구에서는 영산강유역의 본류를 대표하는 나주지점을 대상으로 2003년 1월 1일 00시부터 2004년 12월 31일 23시까지 17,544개의 시수위 자료에 대하여 해당 년도의 Rating-Curve식을 적용 환산한 유출량자료에 데한 카오스적 특성을 분석하였다. 카오스적 특성을 분석하기에 앞서 원자료에 대하여 이동평균법과 Savitzky-Golay Filter를 적용하여 잡음을 제거하였으며, 1차원의 단일변량의 자료에 대한 상태공간(Phase Space)의 재건을 통하여 비교검토 하였다. 이러한 일련의 과정을 거친 자료에 대하여 상관차원법을 이용하여 영산강 유역의 나주지점의 시유출량 자료에 대한 카오스적 특성을 분석한 결과 저차원의 수렴으로 카오스 특성을 가졌다.

  • PDF