Question

Researchers wanted to determine if single individuals having a pet is associated with less depressive symptoms. The researchers administered a standardized emotional health questionnaire to 500 randomly selected singles, 250 of which have a pet and the other 250 do not. After analyzing the results, the researchers determined that the emotional health score of those individuals that had pets was significantly higher than that of those who did not have a pet. Answer the questions below.

1. Why is this an observational study?
2. What is the response variable in the study?
3. What is the explanatory variable?  

Answer 1

This is an observational study as there is no treatment given here, which would have been administered by the observer. In effect the person making the observation has no control over the test specimen in any way. If he did have a control (how much to give, when to give, how to give etc) then it would have been an experiment.

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The response variable here is the emotional health score as this score is with regards to a response based on having or not having pets.

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The Explanatory variable to having this kind of an emotional score is pets. Because of having pets the emotional score is higher and because of not having pets the emotional score is lower. Therefore pet explain the nature of scores and are the explanatory variables.

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