COURSE
MATH225N: Week 1 Solutions
Act 1
In a survey conducted to find out the feedback of a sports program organized in a club, the organizers asked the respondents to classify their feedback as good, fair, poor, and bad. Is the study observational or experimental? If it is an experiment, what is the controlled factor?
Act 2
A study was performed with a random sample of 513 bolts produced at one factory. What population would be appropriate for generalizing conclusions from the study, assuming the data collection methods used did not introduce biases?
Act 3
In the description of the following experiment, determine the experimental factor. A team of physicians testing a new liquid drug taken using an inhaler for treating colds gave the drug to one group of volunteers enrolled for the test. They gave the other group water using the same kind of inhaler.
Act 4
A researcher wants to evaluate the effect of using Facebook on happiness. Would an experimental or observational study design be more appropriate?
Act 5
In the description of the following experiment, determine the experimental factor. During a study testing a new vaccine drug for Zika virus, the research team grouped the volunteers enrolled for the test into Group A and Group B. Group A received an inert drug (placebo) while Group B received the vaccine drug.
Act 6
A researcher is interested in the effects of watching videos just before bed on the quality of sleep. He has decided to test the claim “Watching 1 hour of video just before going to bed reduces the number of minutes of REM sleep by more than 10%. ” Which of the following data collection processes would be appropriate? Select only one answer choice.
Act 7
In a study to add a new feature to a software program, the programmer introduced two categories, men and women, in the survey she conducted. Is the study observational or experimental? If it is an experiment, what is the controlled factor?
Act 8
A farmer divided his land into 2 groups of sections randomly. There is no difference in the quality of the soil between the 2 groups of land. He used Type A seeds in the first group and Type B seeds in the second group. After 3 months, the heights of the crops are measured across the two groups of land sections. Is the study observational or experimental? If it is an experiment, what is the controlled factor?
Act 9
A consumer research company is interested in determining if a certain company’s new refrigerator model is more efficient than the older model. Researchers decide to investigate the claim that the new model uses 10% less electricity than the older model for the same cooling load. To collect data, the company obtains 20 random refrigerators for each model. They are all placed in one building well separated from each other and are loaded with 50 bottles of water. The electricity usage is monitored for one month. How can the results be generalized?
Act 10
A study was performed with a random sample of 5 people from a certain city. What population would be appropriate for generalizing conclusions from the study, assuming the data collection methods used did not introduce biases?
Act 11
In the description of the following experiment, determine the experimental factor. A research team is testing a paste form of a drug to alleviate inflammation. Participants are grouped into Team A and Team B. Team A receives the paste form of the drug. Team B receives a similar paste with no active ingredients.
Act 12
In the description of the following experiment, determine the experimental factor. A pharmaceutical company conducted an experiment to test a breakfast drink for school children. The company enrolled students for the experiment in the age group of 6 to 10 and divided them into two groups. One group received the new breakfast drink with their normal breakfast, and the other group drank the same amount of a similar looking juice. Identify the experimental factor.
Solution
Act1
In a survey conducted to find out the feedback of a sports program organized in a club, the organizers asked the respondents to classify their feedback as good, fair, poor, and bad. Is the study observational or experimental? If it is an experiment, what is the controlled factor?
Answer: The study is
Act 2
A study was performed with a random sample of 513 bolts produced at one factory. What population would be appropriate for generalizing conclusions from the study, assuming the data collection methods used did not introduce biases?
Answer: The conclusions would…………….please follow the link below to purchase the solution at $5