In: Statistics and Probability
Assume that the differences are normally distributed. Complete parts (a) through (d) below.
Observation Xi Yi
1 48.8 51.1
2 47.4 48.7
3 48.2 50.1
4 48.0 52.1
5 48.6 48.5
6 49.8 53.6
7 51.7 52.8
8 54.3 53.5
(a) Determine di = Xi−Yi for each pair of data. (Type integers or decimals.)
di 1__ 2__ 3__ 4__ 5__ 6__ 7__ 8__
(b)Compute d overbard and sd.
d overbard = __ ?
sd = __?
(c)
Test if μd <0 at the α =0.05 level of significance.
(d) find the P value (rounded to three decimal places)
Number | Before | After | Difference | |
48.8 | 51.1 | -2.3 | 0.36 | |
47.4 | 48.7 | -1.3 | 0.16 | |
48.2 | 50.1 | -1.9 | 0.04 | |
48 | 52.1 | -4.1 | 5.76 | |
48.6 | 48.5 | 0.1 | 3.24 | |
49.8 | 53.6 | -3.8 | 4.41 | |
51.7 | 52.8 | -1.1 | 0.36 | |
54.3 | 53.5 | 0.8 | 6.25 | |
Total | 396.8 | 410.4 | -13.6 | 20.58 |
Test Statistic :-
To Test :-
H0 :-
H1 :-
t = -2.8043
Test Criteria :-
Reject null hypothesis if
Result :- Reject null hypothesis
Decision based on P value
P - value = P ( t > 1.7518 ) = 0.013
Reject null hypothesis if P value <
level of significance
P - value = 0.013 < 0.05 ,hence we reject null hypothesis
Conclusion :- Reject null hypothesis