Quantitative measurements of a simulated cluster dataset.

<p>(A) Representative cluster diameter measurement for a reference image with no repeat localizations. Each cluster is identified by eye, and then fit to a two-dimensional, symmetrical Gaussian distribution (blue mesh). The cluster diameter is measured as the FWHM, calculated as 2.35*σ, where σ is the fitted Gaussian standard deviation. The average FWHM of these four clusters is 74±1 nm. (B) Cluster diameter values (average of four clusters) calculated from images generated by applying different threshold pairs to the same simulated dataset. The measured diameters decrease with increasing threshold values, similarly to the Z-ring width measurement. (C) The fraction of molecules located in clusters (<i>f_cluster</i>) is most similar to that measured in the reference image (0.47) for low values of both <i>d_Thresh</i> and <i>t_Thresh</i>. (D) As with the Z-ring simulation, fractional difference between each reconstructed image and the number of molecules in the reference image (<i>N_ref</i> = 1212) is lowest along two intersecting valleys. (E) The Jaccard index peak position for the cluster simulation is similar to that in the Z-ring simulation where identical kinetic parameters were used (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0051725#pone-0051725-g005" target="_blank">Figure 5B</a>). This simulated dataset was generated using the following parameters: N_total = 2000 (50% in clusters), = 200, FWHM_cluster = 50 nm, σ = 15 nm, blink> = 2, <τ_off> = 1 frame, <τ_on> = 1 frame, <τ⁰_act> = 5 frames (1 frame = 50 ms).