Economics

Feasible Set

Published Apr 29, 2024

Definition of Feasible Set

A feasible set, in the context of economics and optimization, refers to the collection of all possible points of allocation or decision that satisfies a set of given constraints. These constraints can be anything from budget limits, resource availability, technical limits, or any other restrictions that impact the choice set. The feasible set is a fundamental concept in operations research, economics, mathematical programming, and decision sciences, highlighting the range of options available under specified conditions.

Example

Consider a simple example of a manufacturer who produces two types of products: A and B. The manufacturer faces several constraints: a limited budget, limited raw materials, and production capacity constraints. Let’s say, for sake of simplicity, the constraints boil down to these two equations:

– 3A + 2B ≤ 100 (raw material constraint)
– A + B ≤ 50 (production capacity constraint)

The feasible set in this scenario would include all combinations of products A and B that do not exceed the raw material and production capacity constraints. This set can be graphically represented in the two-dimensional space where A and B are on the axes, marked by a polygonal area or region. Any point within (or on the boundary of) this region represents a feasible production plan for the manufacturer.

Why Feasible Set Matters

Understanding the feasible set is crucial in both theoretical and applied economics and business because it outlines the limits within which decision-makers must operate. It helps in identifying all possible options that adhere to the constraints of the situation. For companies, knowing the feasible set means understanding the limits of production capabilities, investment options, or strategic choices given existing resource constraints. Economists, mathematicians, and operations researchers analyze the feasible set to determine optimal or efficient decision points that could maximize or minimize an objective function, such as profit maximization or cost minimization.

The concept is not limited to physical goods but also extends to allocation of time, budgeting decisions, policy making, and much more, making it a versatile tool in decision-making processes across various fields.

Frequently Asked Questions (FAQ)

How does the concept of a feasible set apply to personal budgeting?

In personal budgeting, the feasible set represents all the combinations of spending and saving decisions that fit within an individual’s budget constraints. For instance, the amount spent on rent, utilities, groceries, and other expenses must not exceed the available income. This set helps individuals visualize their financial limitations and plan their expenditures in a way that avoids overspending.

Can the feasible set change over time?

Yes, the feasible set can change over time due to variations in constraints. For example, in a business context, expanding factory capacity, increasing budget, or finding new suppliers can alter the feasible set of production options. Similarly, in a personal finance context, changes in income, expenses, or financial goals can modify an individual’s feasible set of budgetary choices.

How is the feasible set used in optimization problems?

In optimization problems, the feasible set defines the domain within which the optimization process searches for the best (optimal) solution. The objective function, which is to be maximized or minimized, is evaluated only for the points within the feasible set. Optimization techniques, both linear and nonlinear, rely on understanding the feasible set to apply the constraints properly and find the solution that best satisfies the objective while adhering to the limits defined by the constraints.

Identifying and analyzing the feasible set is a fundamental step in the problem-solving process across a wide range of disciplines, highlighting its importance in both theoretical frameworks and practical applications.