Epsilon squared function decomposed on the contributions of every parameter analyzed for two of our models. Left: model with Z = 0.014. Right: model with Z = 0.028. The models computed with the same initial parameters except for β have similar behavior. The shaded area represents the acceptance zone, where the function takes values lower than 0.0485 and the black horizontal line at ϵ² = 0 represents where the modeled parameter equals the observed estimation for it.