Power-law relationships between means and variances of cell density.

<p>Experimentally observed relationships between the means and variances had a slope of (A). When the means and variances were calculated on the basis of lognormal distribution, the slope was (B). Simulation results of the relationships between the means and variances with several assumptions of models were compared with experimentally determined results (C–F). (C) Model parameters were constant, and initial conditions had a lognormal distribution (model-1, ). (D) Model parameters obey truncated normal distribution, and initial conditions were constant (model-2, ). (E) Model parameters displayed truncated normal distributions, and the initial conditions displayed lognormal distributions (model-3, ). (F) Both model parameters and the initial conditions were constant (model-4, ). The time courses of changes in the densities of cells () are used for experimental data. Details are shown in the main text.