In: Statistics and Probability
A sports researcher gave a standard written test of eating habits to 12 randomly selected professionals, four each from baseball, football, and basketball. The results were as follows:
Eating Habit Scores
Baseball Players: 34, 18, 21, 65
Football Players: 27, 28, 67, 42
Basketball Players: 35,44,47,41
Is there a difference in eating habits among professionals in the three sports (using the 0.05 significance level)?
Please use the 5 steps to solve this equation.
Please include the S^2 between / S^within, graphs, and all information neceissary to compute this problem
count, ni = | 4 | 4 | 4 | ||
mean , x̅ i = | 34.500 | 41.00 | 41.75 | ||
std. dev., si = | 21.486 | 18.637 | 5.123 | ||
sample variances, si^2 = | 461.667 | 347.333 | 26.250 | ||
total sum | 138 | 164 | 167 | 469 | |
grand mean , x̅̅ = | Σni*x̅i/Σni = | 39.08 |
square of deviation of sample mean from grand mean,( x̅ - x̅̅)² | 21.007 | 3.674 | 7.111 | ||
TOTAL | |||||
SS(between)= SSB = Σn( x̅ - x̅̅)² = | 84.028 | 14.694 | 28.444 | 127.1667 | |
SS(within ) = SSW = Σ(n-1)s² = | 1385.000 | 1042.000 | 78.750 | 2505.7500 |
no. of treatment , k = 3
df between = k-1 = 2
N = Σn = 12
df within = N-k = 9
mean square between groups , MSB = SSB/k-1 =
63.5833
mean square within groups , MSW = SSW/N-k =
278.4167
F-stat = MSB/MSW = 0.2284
P value = 0.8003
------------------------
Ho: µ1=µ2=µ3
H1: not all means are equal
SS | df | MS | F | p-value | F-critical | |
Between: | 127.17 | 2 | 63.58 | 0.23 | 0.8003 | 4.26 |
Within: | 2505.75 | 9 | 278.42 | |||
Total: | 2632.92 | 11 | ||||
α = | 0.05 | |||||
conclusion : | p-value>α , do not reject null hypothesis |
There is insufficient evidence that means are different.