( ) ( ) ( )( )×=

=η

( )( )∑=

−=

( )−= ∑ =

( )( )

( )( )

( )( )∑

∑∑

=

==

+

+=µ

µ

( ) ( ) ( ) ( ){ }[ ]( )

−=

( ) ( )( ) ( )×−=