Kruizenga had been employing as his asset price model a discrete random walk analogous to Regnault's, rather than Bachelier's continuous-time random walk, and must have been discomfited to discover "after most of my analysis had been completed" (Kruizenga 1956, p. 180) that someone else had analyzed the same topic, half a century before, in a mathematically more sophisticated way.

Donald MacKenzie, An Engine, Not a Camera, loc. 284