Concept explainers
In Exercises 1–4, use these results from a USA Today survey in which 510 people chose to respond to this question that was posted on the USA Today website: “Should Americans replace passwords with biometric security (fingerprints, etc)?” Among the respondents, 53% said “yes” We want to test the claim that more than half of the population believes that passwords should be replaced with biometric security.
4. Requirements and Conclusions
a. Are any of the three requirements violated? Can the methods of this section he used to test the claim?
b. It was stated that we can easily remember how to interpret P-values with this: “If the P is low, the null must go.” What does this mean?
c. Another memory trick commonly used is this: “If the P is high, the null will fly.” Given that a hypothesis test never results in a conclusion of proving or supporting a null hypothesis, how is this memory trick misleading?
d. Common significance levels are 0.01 and 0.05. Why would it be unwise to use a significance level with a number like 0.0483?
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Student Workbook For Elementary Statistics
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