Concave Functions, Convex Functions, and Their Periphery

In constrained optimization problems, the target functions are often concave functions, and functions that are slightly enhanced or relaxed versions of concave functions, i.e., strictly concave functions, strictly quasiconcave functions, semistrictly concave functions, quasiconcave functions, strictly pseudoconcave functions, and pseudoconcave functions. Therefore, this chapter describes the properties and interrelationships of these various functions.