In this study, local prediction method is used to predict O-3 concentration
over Istanbul City at different stations. Observed single-variable time se
ries data are used to reconstruct the attractor in the multidimensional spa
ce. Subsequently, the dynamic model to generate the attractor is estimated
and the change of the trajectory is predicted by a polynomial approximation
. In other words, the dynamics of system are described step by step locally
in the phase space. Parameters needed to reconstruct the phase space are d
elay time and embedding dimension. The delay time is chosen as the lag time
at which the autocorrelation function first reaches to zero. The embedding
dimension is obtained from the plot of correlation coefficient vs. embeddi
ng dimension. This embedding dimension corresponds to minimum relative erro
r between observed and predicted values. The relative error between model o
utputs and observations is within the practically acceptable limits pointin
g out that O-3 concentration is governed by a deterministic chaotic system.
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