N a test population of 1000 people, 210 display hemophilia. you hypothesize that this trait follows mendelian genetics with a 3:1 ratio of non- hemophilia to hemophilia. use the χ2 test to determine whether the data support the hypothesis or not. show your steps and explain your reasoning.
Accepted Solution
A:
According to the 3:1 ratio, you expect, out of a population of 1000 people, 750 non-hemophilia and 250 hemophilia.
The chi-square value can be calculated by the formula: [tex] \chi^{2} = \frac{(O - E)^{2}}{E}[/tex]
where: O = observed value = 210 E = expected value = 250
Therefore: χ² = (210 - 250)² / 250 = 6.4
Now, look at a χ² distribution table, in order to find the p-value. In this case, you have only 1 degree of freedom and the closest χ² is 6.6 which corresponds to a p-value of 0.01.
Since p < 0.05, which is the minimum value generally accepted, we can say that the data do not support the hypothesis.