Single sensitivity indices.

As an index approached 1, the functional became dependent only on that parameter. Most values shown are close to 0, which indicated that nonlinear interactions between parameters dominated the cone flash response. While the theoretical value of the Sobol index must fall in the interval [0, 1], small negative values sometimes occurred above as an artifact of the Monte Carlo approximation. These should be regarded as approximately 0. Confidence intervals are given in S1 Appendix.