Question

A new vaccine was tested to see if it could prevent the ear infections that many infants suffer from. Babies about a year old were randomly divided in

Comparing two groups
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asked 2021-03-05
A new vaccine was tested to see if it could prevent the ear infections that many infants suffer from. Babies about a year old were randomly divided into two groups. One group received vaccinations, and the other did not. The following year, only 328 of 2460 vaccinated children had ear infections, compared to 508 of 2453 unvaccinated children. Complete parts a) through c) below. a) Are the conditions for inference satisfied? A. Yes. The data were generated by a randomized experiment, less than 10% of the population was sampled, the groups were independent, and there were more than 10 successes and failures in each group. B. No. It was not a random sample. C. No. The groups were not independent. D. No. More than 10% of the population was sampled.

Answers (1)

2021-03-06
The correct option is (A) Yes. The data were geenrated by a randomized experiment, less than 10% of the population was sampled, the groups are independent and there were more than 10 success and failiures in each group. Assumptions mentioned above are the basic assumption for two sample test of proportion all which are satisfied in the following case and hence the correct option is (A)
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