STAT 401 Midterm: STAT401 PILACHOWSKI-T SPRING2015 0101 MID SOL

• School: University of Maryland
• Department: Statistics and Probability
• Course: STAT 401
• Professor: All

Document Summary

March 12, 2015 stat 401 exam 1. Note: while we"d like to guarantee that this answer key is 100% correct, there may be typos we missed in the proofreading. If you think an answer is wrong, check with your instructor or ta: (5 points) a random sample of 50 observations produced a mean value of 55 and standard deviation of 6. 25. Answer key a 95% confidence interval and give a verbal interpretation of its meaning. We can be approximately 95% confident that the true population mean is between 53. 27 and 56. 73. 2. a. (4 points) a sample of 14 joint specimens of a particular type gave a sample mean proportional limit stress of 8. 50. Set up the calculation for a 95% lower confidence bound for the true average proportional limit stress of all such joints. (that is, all the numbers must be in place, but do not compute to a numeric answer. )