The CRN computes by transforming an input concentration into an output concentration, which reaches the appropriate level upon convergence. However, since absence of molecules cannot be measured, we employ dual-rail methodology and represent every Boolean variable with two species, denoted \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$X_{hi}, X_{lo}$$\end{document}Xhi,Xlo. Just like we cannot represent both 0 and 1 on an electrical wire, we restrict our CRNs such that either \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$E[|X_{hi}|] \ge M$$\end{document}E[|Xhi|]≥M or \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$E[|X_{lo}|] \ge M$$\end{document}E[|Xlo|]≥M, but not both, can be present when a CRN has stabilised and no further reactions occur. We consider a high concentration output as correct if \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$E[|X_{hi}|] > 0.8 max(X_{hi}) - 1SD(X_{hi})$$\end{document}E[|Xhi|]>0.8max(Xhi)-1SD(Xhi), where 0.8 is a threshold normalised between the values [0, 1], max() is a function that returns the maximum molecular concentration of a species within the CRN and 1SD computes 1 standard deviation from the mean concentration of \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$E[X_{hi}]$$\end{document}E[Xhi]. 1SD returns 0 under the deterministic semantics. Similarly, we consider a low concentration as correct if \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$E[|X_{lo}|] < 0.2 * max(X_{lo}) + 1SD(X_{lo})$$\end{document}E[|Xlo|]<0.2∗max(Xlo)+1SD(Xlo).