function [ss] = coupled_func_Bayesian(theta,data)

ydata_E_tot = data.ydata_E_tot; 
xdata = data.xdata;

[Sigma] = coupled_model_Bayesian(theta,xdata); % MJ/m^3

ss1 = sum((Sigma - ydata_E_tot').^2);

% Sigma(7)
% ss1

ss = ss1;% + ss2 + ss3;