Question

in a survey conducted by a reputable marketing agency, 245 of 1000 adults 19 years of age or older confessed to bringing and using their cell phone every trip to the bathroom (confessions included texting and answering phone calls). complete parts (a) through (f) below

(d) explain why the point estimate found in part (c) is a statistic. explain why it is a random variable. what is the source of variability in the random variable?

why is the point estimate found in part (c) a statistic?

a. the sample size is large.

b. its value may change depending on the individuals in the survey.

c. all pieces of information obtained from surveys are statistics.

d. its value is based on a specific sample.

e. it is being used to make inferences.

why is the point estimate found in part (c) a random variable?

a. its value may change depending on the individuals in the survey.

b. it is being used to make inferences.

c. all pieces of information obtained from surveys are statistics

d. the sample size is large

e. its value is based on a specific sample

Explanation:

A statistic is a numerical characteristic of a sample. Since the point - estimate is based on a specific sample (in this case, the sample of 1000 adults), it is a statistic. A random variable is a variable whose value is determined by the outcome of a random event. Here, the composition of the sample (which individuals are in the sample) is random. So, the value of the point - estimate (which is calculated from the sample) may change depending on the individuals in the survey (because different samples can have different characteristics).

Answer:

For the first question (Why is the point estimate a statistic): D. Its value is based on a specific sample.
For the second question (Why is the point estimate a random variable): A. Its value may change depending on the individuals in the survey.