Figure 8.

The natural logarithm of the ratio of male to female contributions in African-Americans, as inferred from the data of Cheng et al. (2009). (A) The range (excluding infinity, produced when a parameter value is zero), median, and 25th and 75th percentiles of the natural logarithm of the ratio of male to female contributions from $S_1$ (Africans) and $S_2$ (Europeans) separately for the sex-specific contributions that produced $D\le 0.01$ (Equation 25). Values from Africans, $S_1,$ are largely negative, or female biased, whereas contributions from Europeans, $S_2,$ are mostly positive and male biased. Approximately 26.15% of the contributions from Africans are male biased and 9.25% from Europeans are female biased. This pattern is typically observed when a still larger sex bias occurs in the other population. (B) The logarithm of the ratio of male and female contributions from $S_2$ on the y-axis and the corresponding ratio for $S_1$ on the x-axis, plotted by the density of points in 0.05 square bins. For the cases with male bias in Africa $\left(\text{ln}\left(s_1^{\mathrm{m}}/s_1^{\mathrm{f}}\right)>0\right),$ the level of male bias in Europe is also positive; for the cases with female bias in Europe $\left(\text{ln}\left(s_2^{\mathrm{m}}/s_2^{\mathrm{f}}\right)<0\right),$ the level of female bias from Africa is also negative. Parameter sets in which at least one parameter is 0, and therefore we have values of +∞ or −∞ for $\text{ln}\left(s_1^{\mathrm{m}}/s_1^{\mathrm{f}}\right)$ or $\text{ln}\left(s_2^{\mathrm{m}}/s_2^{\mathrm{f}}\right),$ appear in bins on the edge of the plot for convenience. These bins contain a substantial number of parameter sets.