Noise can moderately increase the number of phenotypes accessible by binary networks for intermediate <i>k</i>.

<p>Number of unique phenotypes <i>U</i> accessed for different numbers of gene expression states <i>k</i> and varying degrees of noise <i>σ</i>, for (A) random networks and (B) networks pre-selected for stability. Networks are binary, <i>W</i>_<i>b</i>, network size <i>N</i> = 4, <i>s</i>_off = 0, maximum of <i>T</i> = 100 iterations, and sample size <i>λ</i> = 2.4 × 10⁶. Horizontal dashed lines represent the size of phenotype space: _<i>max</i> = <i>k</i>⁴.