Figure 2.
Graphical illustration of the main parameters in the Ratcliff diffusion model. (δ) Drift rate, indicating the average amount of information that can be extracted from a stimulus and memory and accumulated across time; (β) starting point, indicating an initial bias toward one of the two response alternatives (a starting point at 0.5 indicates no response bias); (α) boundary separation, indicating the amount of evidence that one needs to accumulate before a response can be made; (τ) nondecision time, which encompasses all nondecision processes during encoding and response execution.
