In: Statistics and Probability
Where are the deer? Random samples of square-kilometer plots were taken in different ecological locations of a national park. The deer counts per square kilometer were recorded and are shown in the following table.
Mountain Brush | Sagebrush Grassland | Pinon Juniper |
30 | 15 | 4 |
30 | 57 | 9 |
20 | 21 | 8 |
25 | 23 | 4 |
A) Find SSTOT, SSBET, and SSW and check that SSTOT = SSBET + SSW. (Use 3 decimal places.)
B) Find d.f.BET, d.f.W, MSBET, and MSW. (Use 4 decimal places for MSBET, and MSW.)
C) Find the value of the sample F statistic. (Use 2 decimal places.)
Mountain Brush | Sagebrush Grassland | Pinon Juniper | Total | |
Sum | 105 | 116 | 25 | 246 |
Count | 4 | 4 | 4 | 12 |
Mean, Sum/n | 26.25 | 29 | 6.25 | |
Sum of square, Ʃ(xᵢ-x̅)² | 68.75 | 1080 | 20.75 | |
Standard deviation | 4.787136 | 18.97367 | 2.629956 |
Number of treatment, k = 3
Total sample Size, N = 12
A) SS(between) = (Sum1)²/n1 + (Sum2)²/n2 + (Sum3)²/n3 - (Grand
Sum)²/ N =
1233.500
SS(within) = SS1 + SS2 + SS3 =
1169.500
SS(total) = SS(between) + SS(within) =
2403
B) df(between) = k-1 =
2
df(within) = N-k =
9
df(total) = N-1 = 11
MS(between) = SS(between)/df(between) =
616.75
MS(within) = SS(within)/df(within) =
129.9444
C) F = MS(between)/MS(within) =
4.75