In: Statistics and Probability
Develop the analysis of variance computations for the following completely randomized design. At α = 0.05, is there a significant difference between the treatment means?
Treatment | |||
---|---|---|---|
A | B | C | |
136 | 108 | 92 | |
119 | 115 | 81 | |
112 | 124 | 85 | |
107 | 103 | 102 | |
131 | 107 | 88 | |
113 | 108 | 118 | |
129 | 96 | 111 | |
113 | 115 | 120 | |
103 | 97 | ||
81 | 106 | ||
xj |
120 | 106 | 100 |
sj2 |
112.86 | 137.56 | 187.56 |
State the null and alternative hypotheses.
H0: μA =
μB = μC
Ha: μA ≠
μB ≠
μCH0:
μA ≠ μB ≠
μC
Ha: μA =
μB =
μC H0:
μA = μB =
μC
Ha: Not all the population means are
equal.H0: At least two of the population means
are equal.
Ha: At least two of the population means are
different.H0: Not all the population means are
equal.
Ha: μA =
μB = μC
Find the value of the test statistic. (Round your answer to two decimal places.)
Find the p-value. (Round your answer to four decimal places.)
p-value =
State your conclusion.
Do not reject H0. There is sufficient evidence to conclude that the means of the three treatments are not equal.Do not reject H0. There is not sufficient evidence to conclude that the means of the three treatments are not equal. Reject H0. There is not sufficient evidence to conclude that the means of the three treatments are not equal.Reject H0. There is sufficient evidence to conclude that the means of the three treatments are not equal.
(a)
Correct option:
H0:
Ha:
(b)
From the given data, the following Table is constructed.
Treatment A | Treatment B | Treatment C | Total | |
N | 8 | 10 | 10 | 28 |
960 | 1060 | 1000 | 3020 | |
Mean | 960/8=120 | 1060/10=106 | 1000/10=100 | 3020/28=107.857 |
115990 | 113598 | 101688 | 331276 | |
Std. Dev. | 10.6234 | 11.7284 | 13.6951 | 14.3339 |
From the above Table, ANOVA Table is calculated as follows:
Source of Variation | Sum of Squares | Degrees of Freedom | Mean Sum of Squares | F |
Between treatments | 1831.4286 | 2 | 1831.4286/2=915.7143 | 915.7143/148.64=6.1606 |
Within treatments | 3716 | 25 | 3716/25=148.64 | |
Total | 5547.4286 | 27 |
Test Statistic is given by:
F = 915.7143/148.64= 6.16
(c)
Degrees of freedom for numerator = 2
Degrees of freedom for denominator = 25
By Technology, P - Value = 0.0067
(d)
Correct option:
Reject H0. There is sufficient evidence to conclude that the means of the three treatments are not equal.