A Statistics professor has observed that for several years students score an average of 117 points out of 150 on the semester exam. A salesman suggests that he try a statistics software package that gets students more involved with computers, predicting that it will increase students' scores. The software is expensive, and the salesman offers to let the professor use it for a semester to see if the scores on the final exam increase significantly. The professor will hav pay for the software only if he chooses to continue using it. In the trial course that used this software, 238 students scored an average of 120 points on the final with a standard deviation of 8.9 points. Complete parts a) and b) below. Ho: H = 117 HA: > 117 What is the test statistic? (Round to two decimal places as needed.) What is the P-value? P.value = (Round to four decimal places as needed.) What is the appropriate conclusion? O A. Reject Ho. The change is statistically significant. The software does appear to improve exam scores. O B. Reject Ho. The change is not statistically significant. The software does not appear to improve exam scores.

A Statistics professor has observed that for several years students score an average of 117 points out of 150 on the semester exam. A salesman suggests that he try a statistics software package that gets students more involved with computers, predicting that it will increase students' scores. The software is expensive, and the salesman offers to let the professor use it for a semester to see if the scores on the final exam increase significantly. The professor will hav pay for the software only if he chooses to continue using it. In the trial course that used this software, 238 students scored an average of 120 points on the final with a standard deviation of 8.9 points. Complete parts a) and b) below. Ho: H = 117 HA: > 117 What is the test statistic? (Round to two decimal places as needed.) What is the P-value? P.value = (Round to four decimal places as needed.) What is the appropriate conclusion? O A. Reject Ho. The change is statistically significant. The software does appear to improve exam scores. O B. Reject Ho. The change is not statistically significant. The software does not appear to improve exam scores.

Linear Algebra: A Modern Introduction

4th Edition

ISBN:9781285463247

Author:David Poole

Publisher:David Poole

Chapter7: Distance And Approximation

Section7.3: Least Squares Approximation

Problem 31EQ

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A Statistics professor has observed that for several years students score an average of 112 points out of 150 on the semester exam. A salesman suggests that he try a statistics software package that gets students more involved with computers, predicting that it will increase students' scores. The software is expensive, and the salesman offers to let the professor use it for a semester to see if the scores on the final exam increase significantly. The professor will have to pay for the software only if he chooses to continue using it. In the trial course that used this software, 249 students scored an average of 114 points on the final with a standard deviation of 8.4 points. Complete parts a) and b) below. A. Fail to reject Ho. The change is not statistically significant. The software does not appear to improve exam scores. B. Fail to reject Ho. The change is statistically significant. The software does appear to improve exam scores. C. Reject Ho. The change is not statistically…
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