Exam 6: Hypothesis Testing

Which of the following is correct?

If a two-sided statistical test returns a P-value less than 0.05, then what can be said about the parameter value specified in the null hypothesis?

Typically, the null hypothesis is the statement that we are interested in _____.

Describe the U.S. criminal justice system's assumptions about guilt and innocence using Type I and Type II terminology. Include reference to the concept of significance level as used in the system.

Which of the following is true for a one-sided test?

Consider a null hypothesis in which we state that the mean mass of male and female robins in a population is the same. Which of the following is an appropriate alternative hypothesis?

Describe the relationship between the P-value of a two-sided statistical test and the confidence interval around the value listed in the null hypothesis.

The ability of a statistical test to correctly reject a false null hypothesis is called which of the following?

When calculating the 95% confidence intervals for the parameter value used in a nonsignificant statistical test, the region would usually (but not always) include the value specified in the null hypothesis.

Consider a hypothetical study in which ecologists looked at the sex ratios of clutches of frog eggs. In their sample, there were more clutches with a majority of males compared to those with a majority of females. The P-value of their test was 0.008. What is their best conclusion based on the evidence provided?

As studies increase in sample size, they tend to have more statistical power.

The most commonly used significance level in biology is a value of 0.05.

It is recommended practice to look at the data values prior to deciding whether to perform a one-sided or two-sided test.

Hypothesis testing quantifies how unusual the data are, assuming that the alternative hypothesis is true.

Describe a data set and make two scientific hypotheses: one must be appropriate for studying with a two-sided test and the other must be appropriate for studying with a one-sided test.

Is the null hypothesis always what we expect or hope to be true? Explain why or why not.

Consider a situation in which we calculate a 95% confidence interval that ranges from 35 to 45. If we conducted a two-sided test with the null hypothesis of the population mean equaling 43, what would the likely result of our test be?

Statistical hypotheses are statements about population values whereas scientific hypotheses are statements about natural phenomena that may account for population values.

The alternative hypothesis is usually the hypothesis we would be most interested in determining is correct.

If a one-sided test rejects the null hypothesis, then a two-sided test would have rejected the null hypothesis as well.