Which statement is denoted by H0 and represents the status quo about the population mean?

Which statement is denoted by H0 and represents the status quo about the population mean?

• A. Alternative hypothesis
• B. Two-tail hypothesis test
• C. Null hypothesis
• D. Confidence Interval

Answer: (C)

The key idea is that the null hypothesis is the baseline claim about a population parameter, the default assumption we test against. For the population mean, this means the null is a statement that the mean equals a specified value, μ = μ0. This is the status quo—the idea that nothing has changed from the claimed value. We compare the data to this claim and decide whether there is enough evidence to doubt it in favor of the alternative, which would state that the mean differs (or is greater/less than μ0, depending on the test). The alternative hypothesis is the statement of change or difference, not the baseline. A two-tail test and a confidence interval are different concepts: a two-tail test describes the form of the Ha, while a confidence interval provides a range for the mean and is not a hypothesis about μ itself.

The key idea is that the null hypothesis is the baseline claim about a population parameter, the default assumption we test against. For the population mean, this means the null is a statement that the mean equals a specified value, μ = μ0. This is the status quo—the idea that nothing has changed from the claimed value. We compare the data to this claim and decide whether there is enough evidence to doubt it in favor of the alternative, which would state that the mean differs (or is greater/less than μ0, depending on the test). The alternative hypothesis is the statement of change or difference, not the baseline. A two-tail test and a confidence interval are different concepts: a two-tail test describes the form of the Ha, while a confidence interval provides a range for the mean and is not a hypothesis about μ itself.