William Grasman was awarded a Ph.D. in mathematics from the University of Iowa in 1977. The title of his dissertation is Periodic Solutions of Ordinary Differential Equations in Higher Dimensional Spaces.
The topic of his dissertation is useful for understanding the qualitative behavior of systems in which precise quantitative relationships are unknown. These systems arise frequently in the life sciences. The numbers that affect the behavior of populations of various species can be known only approximately. For that matter, the general functional form of the interactions of species is known only in a general manner as opposed to the much more exact equations of physics.
In recent years, he has been studying probability theory, and is particularly interested in the computation of probability distributions.