$B $B $B>e$X(B: $BDs0F $BLa$k(B: $B%F!<%^8BDjCj=PK!(B   $BL\

$B%F!<%^4XO"Cj=PK!(B

$B@h9TC5n$7$F;D$C$?$b$N$+$i>e0L(B5$BC18l$rA*$V!%$3$NC5n$G$-$k!%(B $B%F!<%^4XO"Cj=PK!$K$h$k%M%C%H%o!<%/$N9=C[4.3$B$K<($9!%(B

$B?^(B: $B%F!<%^4XO"Cj=PK!$N35MW(B

$BK\8&5f$G;HMQ$9$kC18l(Bt$B$N4XO"EY(B$r$ $B$N7W;;<0$O0J2<$NDL$j$G$"$k!%(B

$$\displaystyle r(t;k)=\frac{df_{k$B!$(Bt}}{df_{k}}/\frac{df_{t}}{N}$$ (4.1)

$$k$B$O:G=i$K@_Dj$7$?%-!<%o!<%I!$(B df_{k$B!$(Bt}$B$O?7J9%G!<%?Fb$G$N%-!<%o(B... ...f_{k}}$B$O(Bk$B$,$$

$$$BK\8&5f$G$OogCM$r(B1.0$B$H$9$k!%(B $B$3$N>l9g(Bk$B$,$$