Andrey works at a call center, selling insurance over the phone. While debating over which greeting he should use when calling potential customers - "Howdy!" or "Hiya!" - he decided to conduct a small study.
For his subsequent 500 calls, he chose one of the greetings randomly by flipping a coin. Then, he compared
the percentage of calls he succeeded in selling insurance using each greeting.
What type of a statistical study did Andrey use?
Choose 1
Sample study
Experiment
Observational study