Figure 2

Scatter plots comparing the variance estimators. The upper-left plot shows the strong agreement between s²($\widehat{?}$ _triplet ) and our approximation s²($\widehat{?}$ _pairwise ). From the upper-right and the lower-left plots, it can be seen that both have similar correlation with $s_{bootstrap}^2$($\widehat{?}$ _pairwise ). Finally, the lower-right plot confirms that variance estimation under the assumption of independence can yield a large overestimation of the correct variance.