A function links an input value to an output value. Functions are written in function notation with the name of the function (usually f or g), a variable written in brackets and an expression ...

This is called function notation and is just another way of expressing the relationship between two variables. Therefore, in general y = f (x).

This paper is concerned with the determination of tight lower and upper bounds on the expectation of a convex function of a random variable. The classic bounds are those of Jensen and ...