. Author manuscript; available in PMC: 2010 Jul 22.

Published in final edited form as: Q J Exp Psychol (Hove). 2010 May;63(5):863–891. doi: 10.1080/17470210903091643

Table 1.

Symbols used in the optimal threshold theory.

Symbol	Description
A	Drift rate
ã	Signal-to-noise ratio (squared)
c	Magnitude of noise
D	Delay between response and next stimulus
D_p	Additional penalty delay on error trials
DT	Decision Time
D_total	D + D_p + T₀
ER	Error Rate
q	Relative weight of accuracy
RA	Weighted difference between RR and ER
RR	Reward Rate
RR_m	Modified RR
RT	Reaction Time
s_A	Variability of A
s_t	Variability of T₀
s_x	Variability of x(0)
T₀	Part of RT connected with non-decision processes
x(t)	Integrated difference between evidence supporting two alternatives
z	Decision threshold
z̃	Normalized threshold
z̃_o	Optimal normalized threshold