chap2 .....\chap2_1.m .....\chap2_2.mdl .....\chap2_3.m .....\chap2_4.mdl .....\chap2_5.m .....\chap2_6.mdl .....\chap2_7.mdl .....\chap2_7f.m .....\chap2_8.m .....\chap2_8f.m