Answer:
Since the calculated F= 2.8657 does not lie in the critical region F (2,2)≥ 19 we conclude that there no difference between the means.
Since the calculated F= 205.0819 lies in the critical region F(1,2) ≥ 18.51 we conclude that there is a difference between the standard deviations of the three groups.
The F- statistic for the observed data is 0.101 as calculated by F- test in excel.
Step-by-step explanation:
To conduct an ANOVA randomization test we perform anova without replication in excel.
The data for the test is
Mean Standard Deviation Sample Size
Never
Played Football 7602.5 1074 25
FB with no History 6459.2 779.9 25
<u>FB with Concussion 5734.6 593.4 25 </u>
<u>Total 6598.8 1133.5 75 </u>
<u />
Anova: Two-Factor Without Replication
SUMMARY Count Sum Average Variance
Row 1 2 8676.5 4338.25 21310656.13
Row 2 2 7239.1 3619.55 16127224.25
Row 3 2 6328 3164 13215968.72
Column 1 3 19796.3 6598.766667 886871.7433
Column 2 3 2447.3 815.7666667 58708.90333
<u>ANOVA Table </u>
Source Sum of Degrees Mean
of Variation Square of freedom Squares
<u> SS df MS F P-value </u>
B/w Rows 1401945.703 2 700972.8517 2.8657 0.259
B/w Col 50164633.5 1 50164633.5 205.0819 0.00484
<u>Error 489215.59 2 244607.795 </u>
Total 52055794.79 5
Set up the null and alternate hypotheses :
H0 ; there's no difference between the means and
there's no difference between the standard deviations
against the claim
Ha: there's a difference between the means and
there's a difference between the standard deviations
The significance level is chosen at 0.05
The test statistics to use are
F1= estimated variance from Between Means/ estimated variance from Error SS
F1= s1²/s3²
F1= estimated variance from Between Standard Deviations / estimated variance from Error SS
F2- s2²/s3²
with υ1= (2,2) and υ2(1,2) degrees of freedom.
The critical regions for F (2,2)≥ 19 for 0.05 significance level
and F(1,2) ≥ 18.51 for 0.05 significance level
Since the calculated F= 2.8657 does not lie in the critical region F (2,2)≥ 19 we conclude that there no difference between the means.
Since the calculated F= 205.0819 lies in the critical region F(1,2) ≥ 18.51 we conclude that there is a difference between the standard deviations of the three groups.
The F- statistic for the observed data is 0.101 as calculated by F- test in excel.
