Please, I need help with this question not with software. The old fashion way is very helpful/
6. Ryan wants to know if weather affects mood. To that end, he asks the same 15 people to rate their moods at three different times – when it is raining, when it is sunny and when it is snowing. The data follows. Does weather significantly affect mood? SSsubjects = 100
|
Raining |
Sunny |
Snowing |
|
M=5, s=1.5, n=15 |
M=8, s=1.1, n=15 |
M=8.4, s=3.1, n=15 |
Ho: weather does not significantly affect mood
H1: weather does significantly affect mood
| raining | sunny | Snowing | ||||
| count, ni = | 15 | 15 | 15 | |||
| mean , x̅ i = | 5.000 | 8.00 | 8.40 | |||
| std. dev., si = | 1.500 | 1.100 | 3.100 | |||
| sample variances, si^2 = | 2.250 | 1.210 | 9.610 | |||
| total sum | 75 | 120 | 126 | 321 | (grand sum) | |
| grand mean , x̅̅ = | Σni*x̅i/Σni = | 7.13 | ||||
| square of deviation of sample mean from grand mean,( x̅ - x̅̅)² | 4.551 | 0.751 | 1.604 | |||
| TOTAL | ||||||
| SS(between)= SSB = Σn( x̅ - x̅̅)² = | 68.267 | 11.267 | 24.067 | 103.6 | ||
| SS(within ) = SSW = Σ(n-1)s² = | 31.500 | 16.940 | 134.540 | 182.980 | ||
no. of treatment , k = 3
df between = k-1 = 2
N = Σn = 45
df within = N-k = 42
mean square between groups , MSB = SSB/k-1 =
51.8000
mean square within groups , MSW = SSW/N-k =
4.3567
F-stat = MSB/MSW = 11.8898
P value = 0.0001
| anova table | |||||
| SS | df | MS | F | p-value | |
| Between: | 103.600 | 2 | 51.800 | 11.890 | 0.0001 |
| Within: | 182.980 | 42 | 4.357 | ||
| Total: | 286.580 | 44 |
p value <α=0.05, reject Ho
there is enough evidence that weather does significantly affect mood at α=0.05
Please, I need help with this question not with software. The old fashion way is very...