In microeconomics, a consumer's Marshallian demand function specifies what the consumer would buy in each price and wealth situation, assuming it perfectly solves the Utility Maximization Problem. Marshallian demand is sometimes called Walrasian demand instead, because the original Marshallian analysis ignored wealth effects.
According to the Utility Maximization Problem, there are L commodities with prices p. The consumer has wealth w, and hence a set of affordable packages
The consumer has a utility function
The consumer's Marshallian demand correspondence is defined to be
If there is a unique utility maximizing package for each price and wealth situation, then it is called the Marshallian demand function. See the Utility Maximization Problem entry for a discussion of this definition.
If there are 2 commodities, then a consumer that always chooses to spend half of its income on each commodity would have the Marshallian demand function