Linear Time Series Models for Stationary data - Feweb
Linear Time Series Models for Stationary data - Feweb
Linear Time Series Models for Stationary data - Feweb
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Key concepts of linear time series analysis<br />
Stationarity, second order / weak<br />
A stochastic process yt is said to be stationary in mean and variance,<br />
when the following conditions are satisfied:<br />
E(yt) = µ, Cov(yt, yt−k) = γk,<br />
<strong>for</strong> any t (that is, <strong>for</strong> any position in the time series) and <strong>for</strong><br />
k = 0, 1, 2, . . ..<br />
This defines second order (weak) stationarity.<br />
Chapter 7.1 Heij et al, TI Econometrics II 2006/2007 – p. 5/24