NO.PZ2018062003000078
问题如下：
There are 5 companies in an industry, in the last quarter, the market share data of them are listed as following, the three-firm Herfindahl-Hirschmann Index of this industry is:
选项：
A.0.265.
B.0.335.
C.0.575.
解释：
B is correct
The three-firm Herfindahl-Hirschmann Index of this industry is
0.45^2+0.35^2+0.10^2=0.335
考点：Herfindahl-Hirschmann Index
解析：本题较为常规，直接选取排名前三家公司的数据，带入公式计算即可。
0.45^2+0.35^2+0.10^2=0.335
老师按讲义的工时，求出0.335后不再开根号吗？
