Editing Logistic function (section)

===Sequential analysis===
Link<ref name="A sequential theory of psychological discrimination">{{cite journal|first1=S. W.|last1= Link|journal= Psychometrika|date = 1975|volume= 40|issue= 1 |pages= 77–105|first2= R. A.|last2= Heath|title = A sequential theory of psychological discrimination|doi = 10.1007/BF02291481}}</ref> created an extension of [[Wald's equation |Wald's theory]] of sequential analysis to a distribution-free accumulation of random variables until either a positive or negative bound is first equaled or exceeded. Link<ref name="The Relative Judgment Theory of the Psychometric Function">{{cite book|first=S. W. |last=Link|title= Attention and Performance VII|date= 1978 |pages = 619–630|chapter = The Relative Judgment Theory of the Psychometric Function |publisher = Taylor & Francis|isbn =9781003310228}}</ref> derives the probability of first equaling or exceeding the positive boundary as <math>1/(1+e^{-\theta A})</math>, the logistic function. This is the first proof that the logistic function may have a stochastic process as its basis. Link<ref name="The wave theory of difference and similarity">S. W. Link, The wave theory of difference and similarity (book), Taylor and Francis, 1992</ref> provides a century of examples of "logistic" experimental results and a newly derived relation between this probability and the time of absorption at the boundaries.