Whether the given study depicts an observational study or an experiment. The study involved 250 large-mouth bass in a lake. The 250 large-mouth bass were netted by conservation agents and were observed to determine how many of them were carrying parasites.

Whether the given study depicts an observational study or an experiment. The study involved 250 large-mouth bass in a lake. The 250 large-mouth bass were netted by conservation agents and were observed to determine how many of them were carrying parasites.

Question
Study design
asked 2021-02-11
Whether the given study depicts an observational study or an experiment.
The study involved 250 large-mouth bass in a lake. The 250 large-mouth bass were netted by conservation agents and were observed to determine how many of them were carrying parasites.

Answers (1)

2021-02-12
Justification:
Observational Study: An observational study measures the values of a variable without influencing the values of response variables and explanatory variables. Thus, in observational study, researchers can observe the behaviors of the individuals without influencing the outcome of that study.
Designed experiment: In a designed experimental study, researchers allocate individuals to a certain group under study and change the values of an explanatory variable intentionally, after which, the values of the response variable for each group is recorded.
In a lake, 250 large-mouth bass were netted by conservation agents and the agents wanted to determine how many of them were carrying parasites. The number of parasites being carried by the 250 large-mouth bass was simply recorded. Hence, the given study is an observational study.
However, no attempt was made to influence the number of parasites carried by the individuals of the study. Thus, the given study is not a designed experiment but an observational study.
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