n+n-12(x2-x) n1+n2 ∑(x,-x)+∑(x-x) ny XI+n,X X X nI XI+nx H1+n2 n1+ n1+n2 XI-X n,IX1-Y ∑(xn-x)+2 +2 X1-X1 n1+ +n n1+n2 +∑(x-x:)+/2(E X.-X n1+n2 n, +n n, n2(X1-X2) +2hn2(X1-X2) H1+n2 n1+n2 H1+ +n n tn 1mh2(x1=x2) n2 X1-X2 -2 H1+ n1+n2 n1+n2 (n1+n2-1)(n2+n2) n1n2(X1-X2 H1+ n +n2)(n1+n( ) ( ) ( ) ( ) ( ) ( ) 1 2 1 2 1 2 1 1 2 2 2 1 2 1 2 1 1 1 2 1 2 2 1 2 1 2 1 2 1 2 1 2 1 2 1 1 1 2 1 2 2 2 1 2 2 1 1 1 2 1 1 1 2 1 1 2 1 1 1 1 1 2 1 n n n n k i j k i j n n i j i j n n i i i X X XX X X n n n n nX nX nX nX X X n n n n n n nX X X X n n n n + = = = = = = = ⎡ ⎤ − = ⎢ ⎥ −+ − + − + − ⎣ ⎦ ⎧ ⎫ ⎪ ⎪ ⎡ ⎤ + + ⎡ ⎤ = − +− ⎨ ⎬ ⎢ ⎥ ⎢ ⎥ + − + + ⎪ ⎪ ⎣ ⎦ ⎣ ⎦ ⎩ ⎭ ⎧ ⎡ ⎤ − = − + + ⎢ ⎥ ⎨ + − ⎩ ⎢ ⎥ + ⎣ ⎦ ∑ ∑∑ ∑ ∑ ∑ ∑ ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( )( ) ( ) 1 2 2 1 2 2 1 1 1 2 1 2 2 1 2 1 2 1 1 2 2 2 2 1 1 1 2 1 2 1 2 2 1 2 1 2 1 2 1 2 1 2 1 2 12 12 1 2 12 12 2 2 1 2 1 2 2 2 2 12 12 1 2 1 1 2 1 1 1 1 1 1 1 j n i i n n n j j j j j nX X X X n n nX X nX X X X X X nn nn n nn X X nn X X S nn nn n n nn nn n nn X X S nn nn n = = = = − − + ⎫ ⎡ ⎤ − − ⎪ + −+ − ⎢ ⎥ − ⎬ ⎢ ⎥ + + ⎪ ⎣ ⎦ ⎭ − − − = + + +− +− + +− + − − + + +− +− ∑ ∑ ∑ ∑ i i ( ) ( ) ( )( ) ()( ) ( ) ( )( ) 1 2 1 2 2 2 12 12 2 2 2 1 2 1 2 1 12 2 1 2 1212 2 1 1 1 1 1 nn X X n nn nn n Sn S nn X X nn nn nn − − + +− + − +− − = + +− + +−