MODELLING AND FORECASTING FOR NONSTATIONARY PROCESS MANAGEMENT
Toir Makhamatkhujaev
Shokhjakhon Abdufattokhov
Keywords: Keywords: Non-stationary processes, linear model, complex systems, random walk.
Abstract
Abstract. Predicting the evolution of complex systems is noted as one of the ten grand challenges of modern science. Time series data from complex systems capture the dynamic behaviours and causalities of the underlying processes and provide a tractable means to predict and monitor system state evolution. However, most of the time series observed in our life are nonstationary, often exhibiting trends which can be seen in several forms. Such trends are often removed by differencing the data an appropriate number of times, in which case the series is known as an integrated process. Box and Jenkins recommended this approach, and it is widely used in many research areas. In the paper, a sequence of main steps of the Box-Jenkins model is highlighted and demonstrated in a case study of the Real Gross Domestic Product of the US example. Several simple cases of the ARMA model are introduced and analyzed, followed by building and selecting an appropriate model to explain the evolution of an observed time series.
References
G.P. Zhang, “A neural network ensemble method with jittered training data for time series forecasting”, Information Sciences 177 (2007), p. 5329–5346.
G.P. Zhang, “Time series forecasting using a hybrid ARIMA and neural network model”, Neurocomputing-50 (2003), p. 159–175.
H. Tong, “Threshold Models in Non-Linear Time Series Analysis”, Springer-Verlag, New York, 1983.
K.W. Hipel, A.I. McLeod, “Time Series Modelling of Water Resour
ces and Environmental Systems”, Amsterdam, Elsevier 1994.
J. Faraway, C. Chatfield, “Time series forecasting with neural networks: a comparative study using the airline data”, Applied Statistics 47 (1998), p. 231–250.
J.M. Kihoro, R.O. Otieno, C. Wafula, “Seasonal Time Series Forecasting: A Comparative Study of ARIMA and ANN Models”, African Journal of Science and Technology (AJST) Science and Engineering Series Vol. 5, No. 2, p. 41-49.
http://www.bea.gov/national/pdf/nipaguid.pdf
https://fred.stlouisfed.org/series/GDPC1?utm_source=series_page
&utm_medium=related_content&utm_term=related_resources&utm_campaign=categories