18) Which one of the following examples involves independent samples? A) For 15r

Question

18) Which one of the following examples involves independent samples? A) For 15randomly selected food items, the prices advertised in the local newspaper by two competing supermarkets are recorded. A hypothesis test is then performed to see if there is any mean difference in the prices offered by the two supermarkets. A group of 50students had their blood pressures measured before and after watching a movie con taining violence. The mean blood pressure before the movie was compared with the mean pressure after the movie. C) The effectiveness of a new headache medicine is tested by measuring the amount of time before the headache is cured for patients who use the medicine and another group of patients who use a placebo drug. D) A study is conducted to compare the starting salaries of male and female collegse graduates who find jobs. Pairs are formed by choosing a male and a female with the same-major and similar grade point averages. Suppose a random sample of ten pairs is formed in this manner and the starting salary of each person is conducted.

Explanation / Answer

The answer is c) because in this case, the sample taking the medicine is independent of the sample taking the placebo drug.

WHY a,b and d are not the answers

a) This does not involve independent samples because it depends on the food item chosen as we are comparing prices offered by two supermarkets.

b) The test is being conducted on the same person twice so it cannot be independent.

d) Salaries are being compared in pairs and are dependent on the grades and major of the person for each pair. So, the sample is not independent.

Related Questions

Navigate

• Browse (All)
• Browse 1
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.