The 2004 National Technology Readiness Survey sponsored by the Smith School of Business at the University...
The 2004 National Technology Readiness Survey sponsored by the
Smith School of Business at the University of Maryland surveyed 418
randomly sampled Americans, asking them how many spam emails they
receive per day. The survey was repeated on a new random sample of
499 Americans in 2009.44
(a) What are the hypotheses for evaluating if the average spam
emails per day has changed from 2004 to 2009.
- Ho: μ2004 = μ2009
Ha: μ2004 < μ2009 - Ho: μ2004 = μ2009
Ha: μ2004 ≠ μ2009 - Ho: μ2004 = μ2009
Ha: μ2004 > μ2009 - Ho: μ2004 = μ2009
Ha: μ2004 = μ2009 - 1
(b) In 2004 the mean was 18.5 spam emails per day, and in 2009 this
value was 14.9 emails per day. What is the point estimate for the
difference between the two population means?
spam e-mails per day (please round to one decimal
place)
(c) A report on the survey states that the observed difference
between the sample means is not statistically significant. Explain
what this means in context of the hypothesis test and data.
- This would mean that p ≥ α we reject the null hypothesis and accept the alternative
- This would mean that p ≥ α we accept the null hypothesis
- This would mean that p<α we fail to reject the null hypothesis
Homework Answers
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The 2004 National Technology Readiness Survey sponsored by the
Smith School of Business at the University...
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