Questions from Statistics

Q: The weights of four randomly chosen bags of horse carrots, each

The weights of four randomly chosen bags of horse carrots, each bag labeled 20 pounds, were 20.5, 19.8, 20.8, and 20.0 pounds. Assume that the distribution of weights is Normal. Find a 95% confidence...

Q: Some software (such as SPSS) requires that ANOVA data be

Some software (such as SPSS) requires that ANOVA data be stacked and coded. Some software works with both stacked and unstacked data, and some (such as the TI-84) requires unstacked data. Go back to t...

Q: If you take samples of 40 lines from a random number table

If you take samples of 40 lines from a random number table and find that the confidence interval for the proportion of odd-numbered digits captures 50% 37 times out of the 40 lines, is it the confid...

Q: A researcher collects one sample of 27 measurements from a population and

A researcher collects one sample of 27 measurements from a population and wants to find a 95% confidence interval. What value should he use for t*? (Recall that df = n - 1 for a one-sample t-interva...

Q: A researcher collects a sample of 25 measurements from a population and

A researcher collects a sample of 25 measurements from a population and wants to find a 99% confidence interval. a. What value should he use for t*? (Recall that df = n - 1 for a one sample t-interval...

Q: A random sample of 30 12th-grade students was selected.

A random sample of 30 12th-grade students was selected. The sample mean height was 170.7 centimeters, and the sample standard deviation was 11.5 centimeters. (Source: AMSTAT Census at School) a. State...

Q: A fast-food chain sells drinks that it calls HUGE.

A fast-food chain sells drinks that it calls HUGE. When we take a sample of 25 drinks and weigh them, we find that the mean is 36.3 ounces with a standard deviation of 1.5 ounces. a. State how you wou...

Q: A 2018 Gallup poll asked college graduates if they agreed that the

A 2018 Gallup poll asked college graduates if they agreed that the courses they took in college were relevant to their work and daily lives. The respondents were also classified by their field of stud...

Q: In a 2018 study reported in The New England Journal of Medicine

In a 2018 study reported in The New England Journal of Medicine, Johnston et al. studied the effect of a combination of the drug clopidogrel and aspirin on reducing the rate of recurrent stroke among...

Q: Treatment In a 2018 study by Zhu et al. reported in

Treatment In a 2018 study by Zhu et al. reported in The Lancet, researchers conducted an experiment to determine the efficacy and safety of the drug dorzagliatin in the treatment of patients with Type...