Independent random samples of the scores of 10 daily quizzes from ...

[lbcchick]

Independent random samples of the scores of 10 daily quizzes from day students and 15 quizzes from evening students were gathered. It was decided to use the Mann-Whitney-Wilcoxon test to determine if there is a significant difference between the populations of scores for the two groups of students.
 a. Provide the hypotheses for this test.
  b. Compute the mean W.
  c. Compute the standard deviation W.
  d. The sum of the ranks for the day students was determined to be 184.5 . Compute the test statistic z.
  e. Use  = .05 and test to determine if there is a significant difference in the populations of the scores of the two groups.

Question 2

_____ can be used to determine the percentage of data values that must be within one, two, and three standard deviations of the mean for data having a bell-shaped distribution.
 a. Chebyshev's theorem
  b. The empirical rule
  c. A five-number summary
  d. A box plot

[ynlevi]

Answer to Question 1

a. H0: The two populations are identical
Ha: The two populations are not identical
b. 130
c. 18.0278
d. 3.00
e. p-value = .0026 <  = .05; the null hypothesis is rejected; populations are not identical, there is significant difference between the populations of scores for the two groups of students.

Answer to Question 2

b

[lbcchick]

Excellent

[Viet Thy]

Gracias!