1. p. 863 column 2, lines 17-20: Replace the sentence "An allele is defined as being in the nonancestral state if, during the time since the ancestor, at least one crossover has occurred between the site of the allele and the center locus." by the sentence "An allele is defined as being in the nonancestral state if one of the following two conditions holds: (i) the allele lies on a haplotype whose center locus is nonancestral (meaning that the center locus is not descended from the ancestral haplotype and the center locus is not a mutated descendant of the ancestral haplotype) or (ii) the allele lies on a haplotype whose center locus is ancestral or is a mutated descendant of the ancestral haplotype, and, during the time since the ancestor, at least one crossover has occurred between the site of the allele and the center locus." 2. p. 863 column 2, equation (5): m'(l,tau) should be replaced by m'(l+1,tau) everywhere it occurs in this matrix. 3. p. 863 column 2, bottom of the page: m'(l,tau) should be replaced by m'(l+1,tau) everywhere it occurs in this matrix. 4. p. 864 column 1, line 10: Replace f(i|j) by f(j|i). 5. p. 874 column 2, line 14: Replace sum from i=1 to infinity by sum from i=0 to infinity. (The authors would like to thank Jian Zhang.)