Figure 23: Distribution of the conservation score S(R).
From: Initial sequencing and comparative analysis of the mouse genome
The empirical distribution of S(R) for all 1.9 million non-overlapping 50-bp windows (blue) containing at least 45 aligned ancestral repeat sites (standard deviation 1.19) and 1.7 million non-overlapping 100-bp windows (green) containing at least 50 aligned ancestral repeat sites (standard deviation 1.23). Both curves are bell-shaped, with a mean of zero, but the standard deviations are higher than would be expected if the sites in each window were independent and conserved with (locally estimated) probability µ, . In that case the distribution of S would be approximately normal with a standard deviation of 1. Thus, these data show that there is some dependency between the substitutions within the window.
