Concept explainers
Cell phones If you want to conduct a study with humans to see whether cell phone use makes brain cancer more likely, explain why an observational study is more realistic than an experiment.
Explain why an observational study would be more realistic than an experiment for conducting a study with humans to see whether cell phone use makes brain cancer more likely.
Explanation of Solution
The given information is that, a study is to be conducted to see whether cell phone use makes brain cancer more likely.
Observational study:
When the subjects in a study are just observed for the values of the response variable without imposing any treatments, it is termed as observational study.
Experimental study:
When the subjects in a study are assigned to different experimental conditions for observing the outcome of the response variable, it is termed as experimental study. The experimental conditions that are assigned to the subjects are termed as treatments.
Justification: The researcher is interested to test whether cell phone use makes brain cancer more likely. The researcher cannot assign the subjects to the condition of using cell phone which causes brain cancer because it is unethical.
If the researcher can collect the random sample by just observing who are suffering from brain cancer and their cell phone usage, which would be more appropriate. Hence an observational study would be more realistic than an experiment
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Chapter 4 Solutions
Statistics: The Art and Science of Learning from Data (4th Edition)
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