In: Statistics and Probability
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 Consider the data in the table collected from three independent populations.  | 
 Sample 1  | 
 Sample 2  | 
 Sample 3  | 
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| 
 4  | 
 3  | 
 4  | 
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 a) Calculate the total sum of squares (SST) and partition the SST into its two components, the sum of squares between (SSB) and the sum of squares within (SSW).  | 
 2  | 
 2  | 
 2  | 
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 9  | 
 1  | 
 1  | 
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 5  | 
b) Use these values to construct a one-way ANOVA table.
c) Using alphaαequals=0.05,
what conclusions can be made concerning the population means?
For the given data using Anova Single Factor in Excel we get output as
| Anova: Single Factor | ||||||
| SUMMARY | ||||||
| Groups | Count | Sum | Average | Variance | ||
| Sample 1 | 3 | 15 | 5 | 13 | ||
| Sample 2 | 3 | 6 | 2 | 1 | ||
| Sample 3 | 4 | 12 | 3 | 3.333333 | ||
| ANOVA | ||||||
| Source of Variation | SS | df | MS | F | P-value | F crit | 
| Between Groups | 14.1 | 2 | 7.05 | 1.298684 | 0.331368 | 4.737414 | 
| Within Groups | 38 | 7 | 5.428571 | |||
| Total | 52.1 | 9 | 
( a ) From the above output
SST = 52.1
SST = SSB + SSW
= 14.1 + 38
= 52.1
( b ) one-way ANOVA table.
| ANOVA | ||||||
| Source of Variation | SS | df | MS | F | P-value | F crit | 
| Between Groups | 14.1 | 2 | 7.05 | 1.298684 | 0.331368 | 4.737414 | 
| Within Groups | 38 | 7 | 5.428571 | |||
| Total | 52.1 | 9 | 
( c ) P value < l.o.s
0.3314 > 0.05
So fail to reject H0
At α = 0.05 l.o..s there is enough evidence that all population means are equal