Simulation with 631 COG alignments. Error analysis from a simulation study using 631 COG alignments. Ten reads were simulated from each taxon of each alignment, and then binned according to the likelihood weight ratio of their best placement; ranges for the four bins are indicated in the legend. There is one scatter point in the plot for each bin of each alignment: the x-axis for each plot shows the number of taxa in the tree used for the simulation, and the y axis shows the average error for that bin. For example, a point at (100, 1.2) labeled 0.5 - 0.75 indicates that the set of all placements for an alignment of 100 taxa with confidence score between 0.5 and 0.75 has average error of 1.2. As described in the text, the error metric is the number of internal nodes between the correct edge and the node placement edge.