Utility

Chapter 3: Consumer's Equilibrium - Utility Analysis

1. Who is a Consumer?

  • Definition: A consumer is an economic agent using goods and services for satisfaction of wants.

  • Entities: Consumers can be individuals, institutions, or groups/households.

  • Consumer behavior: Refers to the spending patterns of consumers.

  • Utility derived: Consumers maximize utility based on income and prices of goods/services.

2. Concept of Utility

  • Definition: Utility is the satisfaction derived from consuming a commodity or its want-satisfying power.

  • Example: Drinking a cup of tea provides satisfaction termed as 'utility'.

3. Measurement of Utility: Cardinal and Ordinal Measurement

  • Cardinal Measurement (Alfred Marshall): Utility can be quantified in units called 'utils'. Example: A cup of tea may provide 2 or 3 utils of satisfaction.

  • Ordinal Measurement (J.R. Hicks): Satisfaction can only be ranked (higher or lower) without exact units.

  • Focus: This chapter focuses on cardinal measurement for consumer's equilibrium analysis.

4. Concepts of Total Utility and Marginal Utility

  • Total Utility (TU): The total satisfaction received from consumption of all units of a commodity.

    • Example: Two units consumed leading to 10 and 9 utils results in total utility of 19 utils.

  • Marginal Utility (MU): The additional satisfaction from consuming an extra unit of a commodity.

    • Formula: MU = TU(n) - TU(n-1)

    • Example: If 11 units yield 105 utils and 10 units yield 100 utils, marginal utility of 11th unit is 5 utils.

5. Law of Diminishing Marginal Utility

  • Description: As more units of a commodity are consumed, the additional satisfaction gained (marginal utility) tends to decrease.

  • Implication: Total utility increases at a diminishing rate; e.g., 100, 90, 80, 70 utils from consecutive units.

  • Fundamental Law: Every additional unit yields less satisfaction, known as the 'Fundamental Law of Satisfaction'.

6. Concept of Consumer's Equilibrium

  • Definition: A state where a consumer maximizes satisfaction with their income without a tendency to change expenditure.

  • Assumptions:

    • Rational consumer aiming for maximum satisfaction.

    • Measurement of utility in cardinal numbers.

    • Utility from one good is independent of other goods.

    • Constant marginal utility of money.

7. Marginal Utility Analysis and Consumer's Equilibrium

  • Question Addressed: How does a consumer maximize satisfaction?

  • Key Factors:

    • Price of the commodity.

    • Marginal (and total) utility of the commodity.

    • Marginal utility of money.

  • Marginal Utility of Money: Worth of a rupee in terms of utility expected from a basket of goods.

  • Example of Equilibrium: If marginal utility of x is greater than its price, consumer continues purchasing until values equalize.

8. The Basic Limitation of Utility Analysis

  • Limitation: Utility expressed in cardinal numbers is often unrealistic; satisfaction often cannot be accurately measured in units.

  • Critique: Hicks challenged the practicality of this analysis; proposed Indifference Curves as an alternative method for equilibrium.

9. Conclusions on Consumer's Equilibrium

  • Importance of utility analysis in understanding consumer behavior and satisfaction maximization.

  • The application of cardinality and recognition of limitations provide a foundation for further economic theories.