Ohio Assessments for Educators (OAE) Mathematics Practice Exam

What symbol represents the mean for a population?

1. σ

2. µ

3. ⁻x⁻

4. s

The correct answer is: µ

The symbol that represents the mean for a population is µ (mu). In statistics, the mean is a measure of central tendency that indicates the average value of a set of data. For populations, this value is often represented by the Greek letter µ. In contrast, the other symbols mentioned serve different purposes in statistical notation. For example, σ (sigma) denotes the standard deviation of a population, which measures the extent to which data points vary from the mean. The symbol ⁻x⁻ (x-bar) is used to represent the sample mean, which is the average of a sample taken from the population, rather than the population itself. Finally, s represents the standard deviation of a sample, which is also a measure of variation but specifically pertains to sample data. Thus, µ is distinctively used to signify the mean of the entire population, making it the correct answer in this context.