Statistics Questions & Answers

Statistics Questions & Answers a correlation coefficient close to 1 is evidence of a cause and effect relationship between the two variables - ANSWER: false a medical study was investigating if getting a flu shot actually reduce the risk of developing the flu. From a group of adult volunteers, researchers randomly assigned half to receive an injection that contain the drug believed to reduce the risk of getting the flu and the other half to receive an injection containing no active ingredient. A hypothesis test was performed and a P value of 0.0002 was obtained. Which of the following statements is true? - ANSWER: WRONG: the small P value indicates strong evidence to reject the null hypothesis. Even though an experiment was performed causation cannot be inferred. That is, it cannot be concluded that the reduction in the risk of getting the flu was caused by the flu shot a medical study was investigating whether getting a flu shot actually reduce the risk of developing the flu. A hypothesis test is to be performed. Which of the following statements is correct? - ANSWER: WRONG: a two tailed test will be performed since the alternative hypothesis states that the parameter is not equal to the hypothesized value a one sample test is to be performed. Researchers are wondering if the normality condition is met. The normal probability plot below was constructed Based on data collected on gpa's from a random sample of college students based on the normal probability plot, which of the following statements is correct? - ANSWER: WRONG: gpas of college students in this sample are approximately normally distributed. However because the sample is not representative of the population of all college students it cannot be said that the gpas of all college students follow a normal distribution. a one sample test is to be performed. Researchers are wondering if the normality condition is met. The normal probability plot below was constructed based on the data collected on gpa's from a random sample of college students. Based on the normal probability plot, which of the following statements is correct? - ANSWER: WRONG: gpas of college students in this sample are not approximately normally distributed. However because the sample is not representative of the population of all college students, it could be possible that the gpas of all college students follow a normal distribution.