In: Statistics and Probability
The accompanying data represent the pulse rates (beats per minute) of nine students. Treat the nine students as a population. Compute the z-scores for all the students. Compute the mean and standard deviation of these z-scores.
STUDENT PULSE
student 1 77
student 2 61
student 3 60
student 4 80
student 5 73
student 6 80
student 7 80
student 8 68
student 9 73
Compute the z-scores for all the students. complete the table. (round to the nearest hundredth as needed)
STUDENT Z-SCORE
student 1 ___
student 2 ___
student 3 ___
student 4 ____
student 5. ____
student 6. ____
student 7. ____
student 8. _____
student 9. _____
Now, compute the mean of these z-scores. (round to the nearest tenth as needed.)
The mean of the z-scores is ___.
Now, compute the standard deviation of these z-scores. (round to the nearest tenth as needed.)
The standard deviation of the z-scores is ____.
Given : Population:
Let X : the pulse data
STUDENT | X: PULSE |
Student1 | 77 |
Student2 | 61 |
Student3 | 60 |
Student4 | 80 |
Student5 | 73 |
Student6 | 80 |
Student7 | 80 |
Student8 | 68 |
Student9 | 73 |
Population Mean :
N: Population Size = Number of students in the population = 9
Population Standard deviation :
STUDENT | X: PULSE | X- | (X-)2 |
Student1 | 77 | 4.5556 | 20.75349 |
Student2 | 61 | -11.4444 | 130.9743 |
Student3 | 60 | -12.4444 | 154.8631 |
Student4 | 80 | 7.5556 | 57.08709 |
Student5 | 73 | 0.5556 | 0.308691 |
Student6 | 80 | 7.5556 | 57.08709 |
Student7 | 80 | 7.5556 | 57.08709 |
Student8 | 68 | -4.4444 | 19.75269 |
Student9 | 73 | 0.5556 | 0.308691 |
Total | 652 | 498.2222 | |
Mean: | 652/9=72.4444 |
STUDENT | X: PULSE | (X-72.444) | Z-score=(X-72.444)/7.4403 |
Student1 | 77 | 4.5556 | 0.612 |
Student2 | 61 | -11.4444 | -1.538 |
Student3 | 60 | -12.4444 | -1.673 |
Student4 | 80 | 7.5556 | 1.015 |
Student5 | 73 | 0.5556 | 0.075 |
Student6 | 80 | 7.5556 | 1.015 |
Student7 | 80 | 7.5556 | 1.015 |
Student8 | 68 | -4.4444 | -0.597 |
Student9 | 73 | 0.5556 | 0.075 |
Z-Score Table For all the students
STUDENT | Z-score |
Student1 | 0.612 |
Student2 | -1.538 |
Student3 | -1.673 |
Student4 | 1.015 |
Student5 | 0.075 |
Student6 | 1.015 |
Student7 | 1.015 |
Student8 | -0.597 |
Student9 | 0.075 |
STUDENT | Z-score | Z-score- | (Z-score - )2 |
Student1 | 0.612 | 0.612 | 0.375 |
Student2 | -1.538 | -1.538 | 2.366 |
Student3 | -1.673 | -1.673 | 2.797 |
Student4 | 1.015 | 1.015 | 1.031 |
Student5 | 0.075 | 0.075 | 0.006 |
Student6 | 1.015 | 1.015 | 1.031 |
Student7 | 1.015 | 1.015 | 1.031 |
Student8 | -0.597 | -0.597 | 0.357 |
Student9 | 0.075 | 0.075 | 0.006 |
Total | 0.000 | 9.00 | |
Mean: | =0.000/9=0 |
The mean of the z-scores is 0
The standard deviation of the z-scores is 1