MATH 225N Week 2 Statistics Latest Update 2020

MATH 225N Week 2 Statistics Latest Update 2020

Question 1

A company has developed a wristband for monitoring blood sugar levels without requiring direct blood samples. It is interested in demonstrating the accuracy of the device for governmental approval and has decided to test the claim "The glucose level reported by the wristband is within 10% of a standard blood test result." Which of the following data collection processes would be appropriate? Select only one answer choice.

Select the correct answer below:

Choose a random sample of employees at lunchtime and measure their blood sugar using both the wristband and a standard blood test.

Choose a random sample of people from the local area and random times throughout the day and measure their blood sugar using both the wristband and a standard blood test.

Choose a random sample of people from the local area and random times and measure their blood sugar using the wristband. Choose another random sample of people and random times and measure their blood sugar using the standard blood test.

Go to a hospital and have the doctors choose a random sample of patients to be tested at random times using both the wristband and the standard blood test.

Question 2

A farmer divided his piece of land into 4 equivalent groups. The quality of the soil is the same across

the 4 groups of land. He planted the same crop in all 4 groups of land and recorded the yield of the crop in all 4 groups for a 4 week period. Is the study observational or experimental? If it is an experiment, what is the controlled factor?

Select the correct answer below:

The study is an observational study.

The study is an experiment. The controlled factor is the 4 week observation period.

The study is an experiment. The controlled factor is the land.

The study is an experiment. The controlled factor is the growth of the crops.

Question 3

To test the effectiveness of a drug proposed to relieve symptoms of headache, physicians included participants for a study. They gave the drug to one group and a drug with no therapeutic effect to another group. Which group receives the placebo?

Select the correct answer below:

the physicians

the group that received the drug for headache

the group that received the drug with no therapeutic effect all of the people in the study