Part I

Part II

Part III

Summarizing

F2 Data

F2 Progeny Part I

F2 Progeny Part II

Standard Error Of 'p', The Recombination Fraction

Summary

The Amount Of Information And Its Uses

Homework
Questions Assignment #5

Homework
Answers
Assignment #5

Part III

Back to our Maximum Likelihood estimate of r. The general formula is:

L = C + a1 log m1 + a2 log m2 +...+ ai log mi

We take the first derivative of L with respect to r and set this equal to zero to maximize r.

  Numbers
Classes Observed Expected
PpTt a1 m1 = (1- r)/2
pptt a4 m4 = (1- r)/2
Pptt a2 m2 = r/2
pptt a3 m3 = r/2

We have shown that m = 1/2(1-r) where we multiply 1/2(1-r) for a single event by n to get the total number expected for n progeny.

Because we substituted m = (1 - r)/2, etc.

n/2 is a constant so when q = a log (1-r)

dq = -  a   because   d log (1-r) = -    1 
dr      1-r  because   d lodr(1-r) = -   1-r

Copyright 2000©, Ted Helms

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