(2 points) Which of the following represents a two-tailed hypothesis test?

In a certain city, 1% of the population has a rare disease. A medical test for the disease is 99% accurate for both true positives and true negatives. That is:- If a person has the disease, the test will be positive 99% of the time.- If a person does not have the disease, the test will be negative 99% of the time.A randomly selected person from the city tests positive. What is the probability that this person actually has the disease?

(2 points) A researcher fits a regression model and finds that all the predicted y-values fall close to the actual values. What does this suggest?

(2 points) A researcher is studying the effect of sleep duration on student test performance but doesn’t account for caffeine intake. In this case, what role does caffeine consumption play in the study?

(2 points) During a community health survey, a researcher organizes participant ages into intervals and calculates both cumulative frequency and cumulative relative frequency. What is the key benefit of using cumulative relative frequency over just cumulative frequency?

(2 points) Which statement best describes the situation when the addition rule simplifies to P(A or B) = P(A) + P(B)?

(2 points) A biologist records the growth rates (in cm/day) of a plant species under three different conditions: 2, 4, and 8 cm/day. Which measure of central tendency is most appropriate to report the average growth rate when the rates are multiplicative (i.e., the conditions compound the effect)?

(2 points) What does the power of a test (1 – beta) represent?

(2 points) What is the purpose of the randomized blocks design in experimental studies?

(2 points) In statistical analysis, what is described by the term “statistic”?