In: Statistics and Probability
ANOVA Worksheet
Chapter 13 “Too Groups Too Many”
An analysis of variance (also known as ANOVA) is used to test the difference between and within groups when there are more than two levels (in comparison to the t-test).
F-test Statistic
“Simple ANOVA involves testing the difference between the means of more than two groups on one factor or dimension” (Salkind, 2017).
Equation for simple ANOVA:
F= MSbetween
MSwithin In simple words: the variance between groups divided by the variance within groups.
Group 1 Scores |
Group 2 Scores |
Group 3 Scores |
58 |
67 |
89 |
67 |
73 |
90 |
54 |
82 |
87 |
69 |
78 |
92 |
72 |
81 |
89 |
59 |
76 |
79 |
67 |
79 |
82 |
ANOVA |
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Scale |
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Sum of Squares |
df |
Mean Square |
F |
Sig. |
|
Between Groups |
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Within Groups |
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Total |
Solution-
ANOVA Table-
Sum of square | DF | Mean Square | F value | P-value | |
---|---|---|---|---|---|
Between Groups | 1882.286 | 2 | 941.143 | 30.251 | 0.0000 yes, significant |
Within Groups | 560 | 18 | 31.111 | ||
Total | 2442.286 | 20 |
by the test results p < 0.05
So, we have enough evidence to claim that groups of scores are significantly different.
◆ ANOVA calculation and results-