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A sociologist focusing on popular culture and media believes that the average number of hours per week (hrs/week) spent using social media is greater for women than for men. Examining two independent simple random samples of 100 individuals each, the researcher calculates sample standard deviations of 2.3 hrs/week and 2.5 hrs/week for women and men respectively. If the average number of hrs/week spent using social media for the sample of women is 1 hour greater than that for the sample of men, what conclusion can be made from a hypothesis test ?

Suppose that a lifetime of a component (in hours) , X, is modeled with a Weibull distribution with  and . Determine . (i.e. Given that the system has lasted more than 3000 hours, what is the probability it will last for more than 6000 hours?)

Web crawlers need to estimate the frequency of changes to Web sites to maintain a current index for Web searches. Assume that the changes to a Web site follow a Poisson process with a mean of 6 days. Let a random variable X denote the time (in days) until the next change.   What is the probability that the next change occurs in less than 4.5 days?

A company claims that 9 out of 10 doctors recommend its brand of cough syrup to their patients. To test this claim against the alternative that the actual proportion is less than 90%, a random sample of 100 doctors was chosen which resulted in 97 who indicate that they recommend this cough syrup. Find the P-value for this test.

West Virginia State Board of Education v. Barnette (1943) was significant because it

Which of the following statements regarding the Supreme Court overturning acts of Congress is correct?

In District of Columbia v. Heller, the United States Supreme Court held that the District of Columbia’s handgun ban was an unconstitutional violation of the Second Amendment. In writing the majority opinion, the late Justice Antonin Scalia looked predominantly to the words of the Second Amendment of the Constitution in interpreting its meaning. This judicial philosophy in which judges look strictly to the Constitution and writing of the Founders to interpret what was originally meant at the time the law was written can be described as

Consensus-based practice standards and position statements are forms of clinical practice guidelines.

Clinical prediction rules combine relevant findings to calculate a numeric probability for the presence of a specific disorder or likelihood of an outcome.

A clinical prediction rule used to quantify injury risk that was developed from analysis of data derived from college football players may be confidently applied to youth gymnasts.