Some comparisons were performed in terms of amplitude, peak latency, and duration in the estimated HDR among various modeling methods (e.g., FSM, L2D, ESM, a nonlinear model, and inverse logit model; Lindquist et al., 2009). The inverse logit model was deemed the best among the candidates in both simulations and real data, and slightly more powerful than ESM. However, the comparisons were not optimal. First, the dimensional reduction from the HDR shape in ℝm to the three quantities (amplitude, delay, and duration) in ℝ3 might be compromised in power when detecting the shape subtleties—this point can be highly dependent on the experiment. Secondly, the reliability for the estimation of the three characteristics was suboptimal. For example, the lackluster performance of ESM in Lindquist et al. (2009) might be caused by the inaccurate amplitude based on the first local peak because such an approach could be misleading especially when more than one local peak occurs. Lastly, the final group analyses were still focused on the amplitude with the Student's t-test, an effective dimensional reduction from ℝm to ℝ1.