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stationerity
Ergodicity
STATWNAYIje.ly
random variables
alt called random process of stochastic process
doesn’t Mean variances covariances
A process whose behavior
the joint pdf of all combinations of RVs remain
the same 9 Y
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useful property
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change one skewness kurtosis
any function t Ye y 142 is also
strictly stationery stationery
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identically distributed
five periods fr all t
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is called the autocovariance
is called the autocorrelation
mean is constant over all Elie u
all five periods Ye It for all t
time periods
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constant over
depends on the timedifference tI
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TIME SERIES MODELS
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