Before revision:  There is weak to positive evidence that Hull model is the best nonlinear regression to averaged data only for a minority of the subjects, while its dynamical extension (i) can explain the  totality of data . The noise encountered in all individual responses is white , thus confirming the simplest version of model (iii) but standing in contrast with the colored-noise findings in human performance .
After revision:  There is weak to positive evidence that Hull model is the best nonlinear regression to averaged data only for a minority of the subjects, while its dynamical extension (i) can explain the totality of data with strong to very strong evidence. Finally, an analysis of short-scale fluctuations of individual responses showed that they are described by random white noise, in contrast with the colored-noise findings in human performance .