A model incorporating prerequisite mathematics performance and other variables deemed to be associated with learning elementary statistics (ES) is developed. The relationship between ES performance and the explanatory variables is well represented by the logistics form. Aptitude, effort and motivation are the only significant explanatory variables of ES performance. Since prerequisite mathematics is not significant, statistical thinking at the tertiary level may be mostly intuitive and non-mathematical. Students with low aptitude experience increasing returns to effort over the first half of the feasible effort interval, while high-aptitude students experience diminishing returns at all levels of effort. The levels of effort required to achieve a minimum pass are interpreted.