More recently,Naylor, Pritchard, and Ilgen (1980) as well as Ilgen and Klein
(1989) stated that motivation is the psychological state or
predisposition of the individual with respect to choices of
behavior, whereas effort is defined as the amount of energy
spent on an act per unit of time. In line with this literature,
motivation and effort are considered as conceptually distinct
here. Effort is a measurable behavior that is impacted
by motivation (Bandura & Cervone, 1986; Deci & Ryan,
1985; Locke, Shaw, Saari, & Latham, 1981).