A study was conducted to determine whether or not magnets were effective in treating lower back pain. The control group was given a sham treatment ( similar to a placebo. Pain was measured using the visual analog scale. Reduction in pain level for the 100 patients given the magnet treatment was an average of 0.49, and a standard deviation of 0.96. Reduction in pain level for the 100 patients given the sham treatment was an average of 0.44, and a standard deviation of 1.4. Test at the 95% confidence level to determine whether or not the magnet therapy was effective. Use a two tailed test of hypothesis. Use the p-value method to form your conclusion. Clearly show what two values you are comparing to make your decision

A researcher wanted to know whether losing one night sleep can affect problem solving. A sample of n = 25 college students was given a problem-solving task at noon on one day and again at noon on the following day. The students were not permitted any sleep between the two tests. For each student, the difference between the first and the second score was recorded: MD = 5 and standard deviation of the difference score was s = 10. Do the data indicate a significant change in problem solving ability? Use a two-tailed test with α = .01. a. The alternative hypothesis in words is  b. The null hypothesis in symbols is  c. The critical t-values are d. The t-statistic is e. Your decision is

Dr. Shoals predicts that people who walk a mile in moderately high heels will have less back pain than when they walk in very high heels. 27 participants walk in 4-inch heels and then 2.5-inch heels. He calculates the standard deviation of the difference scores and finds sD = 3.37. The mean back pain when walking in 4-inch heels is 6.75, and when walking in 2.5-inch heels, it is 3.25. What is the t statistic for this experiment

In the 1800s, German physician Carl Reinhold, took millions of axillary (i.e. armpit) temperatures from soldiers. This study established that body temperature is normally distributed and the standard normal human body temperature is 98.6°F with a standard deviation of 0.72 °F. In a recent study, American researchers obtained 5,000 axillary temperatures from a Los Angeles hospital. The mean of these temperature readings was 97.9 °F. Assuming a Type I error risk of no more than 5%, did the findings support the theory that human, body temperature has decreased since the 1800s? What is the Z crit?

It takes an average of 12.8 minutes for blood to begin clotting after an injury. An EMT wants to see if the average will change if the patient is immediately told the truth about the injury. The EMT randomly selected 51 injured patients to immediately tell the truth about the injury and noticed that they averaged 14.1 minutes for their blood to begin clotting after their injury. Their standard deviation was 4.48 minutes. What can be concluded at the the a = 0.01 level of significance? a. For this study, we should use Select an answer b. The null and alternative hypotheses would be: Ho: ? v Select an answer V Hj: ? v Select an answer V c. The test statistic ? v = (please show your answer to 3 decimal places.) d. The p-value = (Please show your answer to 4 decimal places.) e. The p-value is ? va f. Based on this, we should Select an answer v the null hypothesis. g. Thus, the final conclusion is that ... O The data suggest the populaton mean is significantly different from 12.8 at a =…

The chocolate chip cookies that are produced at Perry’s Cookie Emporium have weights which are approximately normally distributed with the mean weight 180 grams and with standard deviations 20 grams. The cookies, however, are sold by count, not by weight. Perry wants to improve his image, so he decides to set aside lightest 20% of the cookies to be packaged and sold separately. What cookie weight will divide the lightest 20% from the heaviest 80%?

It takes an average of 10.2 minutes for blood to begin clotting after an injury. An EMT wants to see if the average will decline if the patient is immediately told the truth about the injury. The EMT randomly selected 60 injured patients to immediately tell the truth about the injury and noticed that they averaged 10.1 minutes for their blood to begin clotting after their injury. Their standard deviation was 1.62 minutes. What can be concluded at the the a = 0.01 level of significance? a. For this study, we should use Select an answer b. The null and altemative hypotheses would be: Họ: Select an answer H1: ? Select an answer c. The test statistic (please show your answer to 3 decimal places.) d. The p-value = e. The p-value is (? va f. Based on this, we should Select an answer v the null hypothesis. g. Thus, the final conclusion is that .. (Please show your answer to 4 decimal places.) O The data suggest the population mean is not significantly less than 10.2 at a = 0.01, so there is…

A study reported that the mean concentration of ammonium in water wells in the state of Iowa was 0.71 milligram per liter, and the standard deviation was 1.09 milligrams per liter. Is it possible to determine whether these concentrations are approximately normally distributed. If so, say whether they are normally distributed, and explain how you know. If not, describe the additional information you would need to determine whether they are normally distributed.

It has been reported that the variance of the speeds of drivers on the Turnpike near Somerset, PA is 64 for all vehicles. A driver who was pulled over near Somerset on the pike feels that value is incorrect and conducts a 4. survey of speeds. He finds that the standard deviation of 50 vehicles is 10.5 mph. At a 0.05, is the driver correct? %3D

In the 1800s, German physician Carl Reinhold, took millions of axillary (i.e. armpit) temperatures from soldiers. This study established that body temperature is normally distributed and the standard normal human body temperature is 98.6°F with a standard deviation of 0.72 °F. In a recent study, American researchers obtained 5,000 axillary temperatures from a Los Angeles hospital. The mean of these temperature readings was 97.9 F. Assuming a Type I error risk of no more than 5%, did the findings support the theory that human, body temperature has decreased since the 1800s? What is the Zcrit?