In: Statistics and Probability
three different traffic routes are tested for mean driving time. the entries in the table below are the driving times in minutes on the three different routes. use an ANOVA to test the hypothesis. Route 1: 30, 32, 27, 35 Route 2: 27, 29, 28, 36 Route 3: 16, 41, 22, 31 1) find the numerator degrees of freedom 2) find the denominator degrees of freedom 3) find SS factor 4) find ss total 5) find the F statistic
(1)
N = The total number of subjects = 3 X 4 = 12
k = number of groups = 3
The numerator degrees of freedom = k - 1 = 3 - 1 = 3
(2)
The denominator degrees of freedom = N - k = 12 - 3 = 9
(3)
Route | N | Mean | Std. Dev. |
Route 1 | n1 = 4 | 1=31 | s1 = 3.3665 |
Route 2 | n2 = 4 | 2=30 | s2 = 4.0825 |
Route 3 | n3 = 4 | 3=27.5 | s3 = 10.9087 |
Total | n = 12 | =29.5 | s = 6.5157 |
SS Factor = SSB is given by:
= 26
(4)
SSTotal is given by:
Thus,
(5)
MSB =26/2 = 13
MSW = 440.9996/9 =49
F statistic= 13/49 = 0.2653
So,
Answer is:
0.2653