In: Biology
In a sample of families with 6 children each, the distribution of boys and girls is as shown in the following table:
Number offamilies | 10 | 60 | 147 | 202 | 148 | 62 | 10 |
Number of girls | 0 | 1 | 2 | 3 | 4 | 5 | 6 |
Number of boys | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
Part A) Calculate the chi-square value to test the hypothesis of a boy-to-girl ratio of 1:1. (Express your answer using three decimal places)
Part B) Are the numbers of boys to girls in these families consistent with the expected 1:1 ratio? Yes or No
Part C) Calculate the chi-square value to test the hypothesis of binominal distribution in six-child families. (Express your answer using three decimal places)
Part D) Is the distribution of the numbers of boys and girls in the families consistent with the expectations of binomial probability? Yes or No
Part A & C
First Set of 10 Families | Female | Male | Total | ||||
Observed No (o) | 0 | 6 | 6 | ||||
Expected No (E) | 3 | 3 | 6 | ||||
O-E | 0-3=-3 | 3 | 0 | ||||
(O-E)2 | 9 | 9 | 0 | ||||
(O-E)2/E | 3 | 3 | x2=6 | ||||
in chi square table at p = 0.05, the value should come 3.851 to be significant | |||||||
But our value is larger than this, so it is insignificant and hence hypothesis of a boy-to-girl ratio of 1:1 is Fail | |||||||
First Set of 60 Families | Female | Male | Total | ||||
Observed No (o) | 1 | 5 | 6 | ||||
Expected No (E) | 3 | 3 | 6 | ||||
O-E | -2 | 2 | 0 | ||||
(O-E)2 | 4 | 4 | 0 | ||||
(O-E)2/E | 1.666 | 1.6663 | x2=3.332 | ||||
Our value lies in the range so, the hypothesis can be accepted. | |||||||
First Set of 147 Families | Female | Male | Total | ||||
Observed No (o) | 3 | 3 | 6 | ||||
Expected No (E) | 3 | 3 | 6 | ||||
O-E | 0 | 0 | 0 | ||||
(O-E)2 | 0 | 0 | 0 | ||||
(O-E)2/E | 0 | 0 | x2=0 | ||||
in chi square table at p = 0.5, the value should come near by 0.456 is acceptable | |||||||
This Data is 50% we can say more significant and nearby to accept the hypothesis | |||||||
First Set of 202 Families | Female | Male | Total | ||||
Observed No (o) | 2 | 4 | 6 | ||||
Expected No (E) | 3 | 3 | 6 | ||||
O-E | -1 | 1 | 0 | ||||
(O-E)2 | 1 | 1 | 0 | ||||
(O-E)2/E | 0.333 | 0.333 | x2=0.666 | ||||
in chi square table at p = 0.995, the value should come nearby 0 to be acceptable. | |||||||
This data is more significant and close to accept the hypothesis i.e., 99.5%. | |||||||
First Set of 148 Families | Female | Male | Total | ||||
Observed No (o) | 4 | 2 | 6 | ||||
Expected No (E) | 3 | 3 | 6 | ||||
O-E | 1 | -1 | 0 | ||||
(O-E)2 | 1 | 1 | 0 | ||||
(O-E)2/E | 0.333 | 0.333 | x2=0.666 | ||||
Same Data Is availanle for the next two calculations also so theirfore values will be the same | |||||||
First Set of 62 Families | Female | Male | Total | ||||
Observed No (o) | 5 | 1 | 6 | ||||
Expected No (E) | 3 | 3 | 6 | ||||
O-E | 2 | -2 | 0 | ||||
(O-E)2 | 4 | 4 | 0 | ||||
(O-E)2/E | 1.666 | 1.666 | x2=3.332 | ||||
First Set of 10 Families | Female | Male | Total | ||||
Observed No (o) | 6 | 0 | 6 | ||||
Expected No (E) | 3 | 3 | 6 | ||||
O-E | 3 | 3 | 0 | ||||
(O-E)2 | 9 | 9 | 0 | ||||
(O-E)2/E | 3 | 3 | x2=6 |
Part B : No the consistence ratio of boys and girls are not 1:1
Part D :No