Final answer:
A high Herfindahl-Hirschman Index (HHI) indicates a high degree of market concentration and less competition in the market.
Step-by-step explanation:
A high Herfindahl-Hirschman Index (HHI) indicates a high degree of market concentration, meaning that a few large firms dominate the market. The HHI measures the size of the firms in relation to the total market and is calculated by summing the squared market shares of all the firms in the industry. Higher values of the HHI suggest less competition and potentially higher market power for the dominant firms.