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# Ma3110

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Task 1: 1.1 Define the following terms: A. Population – The collection of all individuals or items under consideration in a statistical study. B. Sample- That part of the population from which information is obtained
(pg. 4)
1.7 Descriptive or inferential
TV Viewing Times. The Nielsen Company collect sand publishes information on the television viewing habits of Americans. Data from a sample of Americans yielded the following estimates of average TV viewing time per month for all Americans 2 years old and older. The times are in hours and minutes (NA, not avail- able). [SOURCE: Nielsen’s Three Screen Report, May 2008]
This is an example of a descriptive form of data, because of the summary of the number of Americans 2 years old and older watching TV.

1.14 Offshore Drilling. A CNN/Opinion Research Corporation poll of more than 500 U.S adults, taken in July 2008, revealed that a majority of Americans favor offshore drilling for oil and natural gas; specifically, of those sampled, about 69% were in favor.
a. Identify the population and sample for this study.

1. Population is 500 U.S adults
2. Sample- 69%
b. Is the percentage provided a descriptive statistic or an inferential statistic> Explain your answer.
1. Inferential because it is measuring the reliability of conclusions about a population based on information obtained.
1.17 The Salk Vaccine. In the 1940s and early 1950s, the public was greatly concerned about polio. In an attempt to prevent this disease, Jonas Salk of the University of Pittsburgh developed a polio vaccine. In a test of the vaccine’s efficacy, involving nearly 2 million grade-school children, half of the children received the Salk vaccine; the other half received a placebo, in this case an injection of salt dissolved in water. Neither the children nor the doctors performing the diagnoses knew which children belonged to which group, but an evaluation center did.

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