MATH 399: Questions and Answers Explained

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 R ...

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%." How should the number of hours of video be treated? 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? A study was conducted among school students on the relationship between getting up late and getting to school late. Is this an example of an observational study or experimental study? If it is an experiment, what is the controlled factor? A candy manufacturer is interested in the distribution of colors in each of its packages of candy sold. Which question is appropriate for their research? A candy manufacturer is interested in the distribution of colors in each of its packages of candy sold. The manufacturer wants to answer the question "What is the typical distribution of colors in a package of candy?" Which data collection method should be used? A researcher wants to find out the effect of the amount of protein eaten at breakfast on the aerobic performance of runners. Would an experimental or observational study design be more appropriate? A statistics student has obtained a sample by surveying all the students in his class. What group can the results of the survey be generalized to? Is an online poll asking the preferred mobile phone type used by school children an observational study or experimental study? If it is an experiment, what is the controlled factor? 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. Which data collection method is appropriate? Select only one answer choice. A statistics student is doing a project for her class. She wants to make a prediction for the outcome of an upcoming national election. Since there are only two candidates, she decides that her question is "Which candidate do more people favor in the upcoming election?" She decides to randomly interview 100 students crossing the courtyard on campus about their preference. Is this sample good for drawing general conclusions about the results of the election? A consumer research company is interested in determining if a certain company's new refrigerator model is more efficient than the older model. What should the researchers do first? A candy manufacturer is interested in the distribution of colors in each of its packages of candy sold. What should the researchers do first? 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? An energy drink manufacturer wants to find out the effect of different amounts of their product on the maximum anaerobic power level for rowers. Would an experimental or observational study design be more appropriate? A researcher is interested in the effects of watching videos just before bed on the quality of sleep. Which of the following claims would be appropriate for this situation? Select only one answer choice. 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? 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? 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. A study was performed with a random sample of 200 people from one college. What population would be appropriate for generalizing conclusions from the study, assuming the data collection methods used did not introduce biases? A consumer research company is interested in determining if a certain company's new refrigerator model is more efficient than the older model. Which might be an appropriate claim to result from this research?