C.G.Clark
potential leading industry
12354
1-234
1-
2
3=512.5110.5
41960
7
123
1
2
3
1J.R.Friedman19661243
1234 10% 10%25% 25%50%
2
1 3 2
3 1988
1234
1 2 3 :
12123
1 2 3 4
:
12313267
1012345678910)
Bird
12 1 break-in-transport Physical break Commercial break Political break 23123
S3
197510%30%70%
18
0.9685821140603801520400-60010020200030% 17