Dynamic factor
(重定向自Diffusion index)
In econometrics, a dynamic factor (also known as a diffusion index) is a series which measures the co-movement of many time series. It is used in certain macroeconomic models.
Formally
where is the vector of lagged factors of the variables in the
matrix
(T is the number of observations and N is the number of variables),
are the factor loadings, and
is the factor error.