I found PACF and ACF like the following table . But, how can I decide whether there exists white noise? And what is white noise? If there is no white noise, can I say being stationary?
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What is white noise? Time series data that shows no auto correlation is called white noise.
How do I know whether it is white noise?
A general assumption is that if 95% of the spikes in the Auto-correlation Function lie within
(+/-)2/sqrt(T), where T being the length of the time series.
So, by the above mentioned formula, one can infer whether the series/data is white noise or not.
A white noise process would not be correlated with its own values at any lag.Its mean is zero, variance is constant and autocovariance(using which the autocorrelation plots like acf and pacf are figured out) is also zero. Thus, your results are clearly indicative of the fact that its not a white noise process.