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MULTISCALE, SELF-SIMILAR FITTING

multiscale fitting self-similar fitting goal ! multiscale self-similar Large objects often resemble small objects. To express this idea we use axis scaling and we apply it to the basic theory of prediction-error filter (PEF) fitting and missing-data estimation.

Equations (3) and (4) compute the same thing by two different methods, $ \bold r = \bold Y \bold a$ and $ \bold r = \bold A \bold y$.When it is viewed as fitting goals minimizing $\vert\vert\bold r\vert\vert$and used along with suitable constraints, (3) leads to finding filters and spectra, while (4) leads to finding missing data.  
 \begin{displaymath}
\left[ 
\begin{array}
{c}
 r_1 \\  
 r_2 \\  
 r_3 \\  
 r_4...
 ...}
{c}
 \bold Y_1 \\  \bold Y_2
 \end{array} \right] 
\;
\bold a\end{displaymath} (3)
 
 \begin{displaymath}
\left[ 
\begin{array}
{c}
 r_1 \\  
 r_2 \\  
 r_3 \\  
 r_4...
 ...rray}
{c}
 \bold A_1 \\  \bold A_2\end{array}\right]
\;
\bold y\end{displaymath} (4)

A new concept embedded in (3) and (4) is that one filter can be applicable for different stretchings of the filter's time axis. One wonders, ``Of all classes of filters, what subset remains appropriate for stretchings of the axes?''