A two-state model of simple reaction time

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the subject enters into Sp is D(x).
As to the exact form of Fp(x) or Fnp(x), the general-gamma
distribution, eqo(4-1), was proposed by McGill and Gibbon(1965)
and the Weibull distribution, eq.(4-2), by Ida(1980)o
i.-=A -Ai.-X
F(x):::: 1- "'[ Ci' e
£-",0
- A.' (t-l-)'17t
F(x) :::: / - e
(4-1)
(4-2)
The general-gamma distribution is obtained when exponential
distributions are summed. The gamma distribution is the special
case of the general-gamma distribution in which the values of
parameters of the exponential distributions are equal to each
other (cf. McGill(1963)). The Weibull distribution is obtained
when the conditional probability at time x that a subject who
has not yet responded will come to respond, rex), obeys the
following equation;
rex) = ):m.(x _ L)m-1
In this article, the aspects of the two-state model which
do not depend on the exact forms of Fp(x) and Fnp(x) are discussed.
Only the relation that the mean of Fp(x) is shorter than the one
of Fnp(x) is assumed.