Suppose that a small town has seven burger shops whose respective shares of the local hamburger market are (as percentages of all hamburgers sold): 28%, 26%, 23%, 10%, 7%, 4%, and 2%.
a. What is the four-firm concentration ratio of the hamburger industry in this town? %.?
b. What is the Herfindahl index for the hamburger industry in this town? .
c. If the top three sellers combined to form a single firm, what would happen to the four-firm concentration ratio and to the Herfindahl index?
The four-firm concentration ratio would be %?. The Herfindahl index would be .