Concept explainers
a.
Explain the meaning of
a.
Explanation of Solution
In Pew research, the random sample of 799 U.S. teens about the internet usage reports that 49% teens misrepresented their age online to access websites and online services.
Let p be the population proportion of the U.S teens who misrepresented their age and
Here,
The
b.
Find the standard error of
b.
Answer to Problem 1E
The standard error of
Explanation of Solution
Calculation:
Standard error:
If the standard deviation of a sampling distribution is estimated by using statistics of the data, the estimate is termed as standard error.
Where, n be the number of samples,
Substitute
Thus, the standard error of
c.
Explain what the standard error in this context.
c.
Explanation of Solution
Interpretation:
Here the value of p is not known. Therefore
When 799 teens are asked whether they misrepresented their age online to gain access to websites and online services, the standard error is the estimate that helps to know the amount of variation in the sample proportion between one sample to another sample.
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Chapter 16 Solutions
Intro Stats
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