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NY Times 18 Sept 2008 front page. 3 mo treasury yield borrowing costs Dow industrials. Stat 153 - 16 Sept 2008 D. R. Brillinger Chapter 3. mean function. variance function. autocovariance. Strictly stationary Normal/gaussian - all joint distributions jointly normal.
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NY Times 18 Sept 2008 front page 3 mo treasury yield borrowing costs Dow industrials
Stat 153 - 16 Sept 2008 D. R. Brillinger Chapter 3 mean function variance function autocovariance
Strictly stationary Normal/gaussian - all joint distributions jointly normal Wide sense stationary vs. second-order
Useful models Purely random Building block
Random walk not stationary
Moving average, MA(q) From * stationary
Backward shift operator Linear process. Need convergence condition
autoregressive process, AR(p) first-order, AR(1) Markov * Linear process For convergence/stationarity
a.c.f. From * p.a.c.f.
In general case, Very useful for prediction
Yule-Walker equations for AR(p). Correlate, with Xt-k, each side of For AR(1)