A vitamin K shot is given to infants soon after birth. Nurses at a hospital were involved in a study to see if how they handle the infants could reduce the pain the infants feel. One of the measurements taken was how long, in seconds, the infant cried after being given the shot. A random sample was taken from the group that was given the shot using conventional methods, and a random sample was taken from the group that was given the shot where the mother held the infant prior to and during the shot. Is there enough evidence to show that infants cried less on average when they are held by their mothers than if held using conventional methods? Test at the 1% level.

Crying Time of Infants Given Shots Using Conventional Methods

61

2

5

44

35

33

29

25

10

10

51

18

30

17

53

37

22

72

61

0

72

37

53

49

38

36

31

55

57

18

Crying Time of Infants Given Shots Using New Methods

31

17

20

17

17

60

1

56

67

66

72

51

45

11

13

57

20

44

17

7

39

75

18

46

9

46

72

26

24

17

State the null and alternative hypotheses.

Ho: H₁? H2

Ha: H1 H2

Calculate the test statistics. Round to two decimal places.

P₁=

P2=

Calculate the standardized test statistic. Round three decimal places.

t=

Find the p-value. Round to four decimal places.

p-value =

State your decision.

Since the p-value is less than 01, fail to reject Ho.

Since the p-value is greater than.01, fail to reject Ho.