Question 59 has two parts. 59. Suppose that in the population of twins, males (M

Question

Question 59 has two parts.

59. Suppose that in the population of twins, males (M) and females(F) are equally likely to occur and that the probability that twinsare identical is . If twins are not identical, their genesare independent.

a. Show that P(MM) = P (FF) = (1+)/4 and P(MF) =(1-)/2

b. Suppose that n twins are sampled. It is found that n1 areMM, n2 are FF, and n3 are MF, but it is not known which twins areidentical. Find the mle of and its variance.

I am embarrassed to admit that I am not sure where to start. Thisquestion is unlike the other questions in this chapter. I will needthe distribution for part (b), and I'm pretty sure the results in(a) come from a summation given the structure. I feel that I may beusing the binomial distribution and the independence axiom.

Can you please help?

Thanks,
Frog

Explanation / Answer

Thanks RAM, I appreciate your help. What you said makes sense. But for part (b), I don't have a jointdistribution. I am supposed to multiply each n (n1, n2, n3) by itsrespective probability (for example, n1 * P(MM) + n2*P(FF)+n3*P(MF))? This would produce a function (with alpha and n's) but after takingthe derivative with respect to alpha, I am left with an equationthat doesn't have an alpha. I must still be missing something. Thanks for any help. Brandon

Related Questions

Navigate

• Browse (All)
• Browse Q
• Subjects

---

---

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