There Are Three Children in a Room, Ages 3, 4

question 1

Multiple Choice

There are three children in a room, ages 3, 4, and 5. If another 4-year-old enters the room:

• A)the mean age will stay the same, but the variance will increase.
• B)the mean age will stay the same, but the variance will decrease.
• C)the mean age and variance will stay the same.
• D)the mean age and variance will increase.

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Definitions:

Herfindahl-Hirschman Index

A measure used to determine the level of competition within an industry, calculated by summing the squares of the market shares for each firm within the industry.

Concentration Ratio

A measure used in economics to assess the degree of market concentration by calculating the market share of the largest firms within an industry.

Market Share

The proportion of total sales or revenue generated by a company within a particular market, compared to the total market size.

Concentration Ratio

The concentration ratio is a measure used in economics to assess the level of competition within an industry by indicating the market share controlled by the top firms.