A two-state model of simple reaction time

and density function d(t).
equation;
- 9 -
From these assumptions, Yellott(1971) derived the following
00
pc·Mc - Pe' Me _ .fot.s(tHl- D(t))·dt
Pc - Pe -.fooos ( t )0 (1 - D(t ) ) , dt
(1-8)
The right side of eq.(1-8) is not in general invariant under
arbitrary transformations of D(x). But, a special version of the
deadline model yields the identical prediction of the fast guess
mode I with a = 1 • That is, the deadI ine modeI can explain the
constancy of the left side of eq.(1-7), too.
As to the speed-accuracy tradeoff, the fast guess model
asserts that the error rate should be constant in order that
the experimenter can controll the subject's strategy. In the fast
guess model, the speed-accuracy tradeoff is controlled by the
probability of guessing. Equality of the error rates between the
experimental conditions means equality of the guessing probabilities
between them. However, according to Ollman(1977)'s adjustable
timing model, invariance of the error rate does not assure
invariance of the strategy.