Although blood type frequencies in the United States are in the ration of 9:8:2:

Question

Although blood type frequencies in the United States are in the ration of 9:8:2:1 for type O, A, B, and AB, respectively, local difference. Two researchers are independently assigned to determine if patients at a particular large city general hospital exhibit blood types supporting the above model. The table below gives the data results from what each researcher claims random samples of 500 patient lab results. (a) Do the data reported by Researcher 1 support the 9:8:2:1 model for blood types of patients at the particular hospital? Justify your answer. (b) The editorial board of a medical publication rejects the findings of Researcher 2, claiming that his data are suspicious in that they are too good to be true. Give a statistical justification for the board's decision.

Explanation / Answer

(A) Null Hypothesis : H0 : Data supported the 9:8:2:1 model for blood type of pateints.

Alternative Hypothesis : Ha : Data doesn't support the 9:8:2:1 model for blood type of pateints.

The observed and expected Table

So value of X2 = 10.544

and for alpha = 0.05 and dF = 3 critical chi- square X2crit = 7.815

p - value = 0.0144

so we can reject the null hypothesis and can say that Data doesn't support the 9:8:2:1 model for blood type of pateints.

(b) Lets see the expected and observed table for the Researcher 2

so here X2 = 0.311

and P - value = 0.958 here so we cannot accept the null hypothesis and we can seee that p - value is approximately near to1, s this type of data are suspicious that they are too good for the true.

Observed Expected (Obs. - Exp.)^2 (Oi- Ei)^2/Ei O 253 225 784 3.484 A 194 200 36 0.18 B 38 50 144 2.88 AB 15 25 100 4 500 500 10.544

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.