In: Math
Are steers and heifers equally distributed between angus and herefords
Case | Breed | Sex | |||
1 | hereford | Heifer | |||
2 | hereford | Heifer | |||
3 | hereford | Steer | |||
4 | Angus | Steer | |||
5 | Angus | Steer | |||
6 | hereford | Heifer | |||
7 | hereford | Heifer | |||
8 | hereford | Heifer | |||
9 | hereford | Steer | |||
10 | hereford | Steer | |||
11 | hereford | Heifer | |||
12 | hereford | Heifer | |||
13 | Angus | Steer | |||
14 | hereford | Heifer | |||
15 | Angus | Steer | |||
16 | hereford | Heifer | |||
17 | Angus | Steer | |||
18 | hereford | Heifer | |||
19 | Angus | Steer | |||
20 | Angus | Steer | |||
21 | Angus | Steer | |||
22 | Angus | steer | |||
23 | Angus | Steer | |||
24 | hereford | Steer | |||
25 | hereford | Steer | |||
26 | hereford | Steer | |||
27 | Angus | Steer | |||
28 | Angus | Heifer | |||
29 | hereford | Steer | |||
30 | Angus | Steer | |||
31 | hereford | Heifer | |||
32 | hereford | Heifer | |||
33 | Angus | Steer | |||
34 | hereford | Steer | |||
35 | hereford | Heifer | |||
36 | hereford | Heifer | |||
37 | Angus | Steer | |||
38 | Angus | Steer | |||
39 | Angus | Heifer | |||
40 | hereford | Steer | |||
41 | hereford | Heifer | |||
42 | Angus | Steer | |||
43 | Angus | Steer | |||
44 | hereford | Steer | |||
45 | hereford | Heifer | |||
46 | hereford | Heifer | |||
47 | hereford | Heifer | |||
48 | hereford | Heifer | |||
49 | hereford | Heifer | |||
50 | hereford | Heifer | |||
51 | Angus | Heifer | |||
52 | hereford | Steer | |||
53 | Angus | Steer | |||
54 | Angus | Steer | |||
55 | Angus | steer | |||
56 | Angus | Heifer | |||
57 | hereford | Heifer | |||
58 | Angus | steer | |||
59 | hereford | Steer | |||
60 | hereford | Heifer | |||
61 | hereford | Heifer | |||
62 | Angus | Heifer | |||
63 | hereford | Steer | |||
64 | Angus | Steer | |||
65 | hereford | Heifer | |||
66 | hereford | Heifer | |||
67 | hereford | Heifer | |||
68 | hereford | Heifer | |||
69 | hereford | Heifer | |||
70 | Angus | Steer | |||
71 | Angus | Steer | |||
72 | Angus | Steer | |||
73 | Angus | Steer | |||
74 | hereford | Heifer | |||
75 | hereford | Heifer | |||
76 | Angus | Steer | |||
77 | hereford | Heifer | |||
78 | hereford | Steer | |||
79 | Angus | Steer | |||
80 | hereford | Heifer | |||
81 | Angus | Steer | |||
82 | hereford | Steer | |||
83 | Angus | Heifer | |||
84 | hereford | Steer | |||
85 | hereford | Steer | |||
86 | hereford | Heifer | |||
87 | hereford | Steer | |||
88 | hereford | Heifer | |||
89 | hereford | Heifer | |||
90 | Angus | Steer | |||
91 | hereford | Heifer | |||
92 | Angus | Steer | |||
93 | hereford | Heifer | |||
94 | Angus | Heifer | |||
95 | Angus | Heifer | |||
96 | hereford | Heifer | |||
97 | hereford | Steer | |||
98 | hereford | Steer | |||
99 | Angus | Heifer | |||
100 | Angus | Steer | |||
The problem can be modeled using chi square test of independence, where the null hypothesis states that -
steers and heifers are equally distributed between angus and herefords
And, alternate hypothesis states that -
steers and heifers are significantly differently distributed between angus and herefords
Simplifying the table -
Steer | Heifer | ||
Angus | 32 | 9 | 41 |
Hereford | 20 | 39 | 59 |
52 | 48 | 100 |
Steer (observed) | Steer (expected) | chi sq | Heifer (observed) | Heifer (expected) | chi sq | Total | |
Angus | 32 | 21.32 | 5.35 | 9 | 19.68 | 5.8 | 41 |
Hereford | 20 | 30.68 | 3.72 | 39 | 28.32 | 4.03 | 59 |
52 | 48 | 100 |
Where, expected value = row total * column total / total
and, chi square value = (observed - expected)^2 / expected
combined chi square value = 18.9
Looking at the chi square table for 1 degree of freedom and value of 18.9, the p value is .000014.
(degree of freedom = (row -1) * (column -1)
The result is significant even at 0.0001 significance level.
Hence, we reject our null hypothesis.
steers and heifers are significantly differently distributed between angus and herefords