Comprehensive Study Notes on Cost Curves and Economic Decisions

Cost Curves and Their Shapes

  • Marginal Cost (MC)

    • Resembles a Nike swoosh shape.

    • Is labeled in a graph for clear understanding of curves.

  • Average Total Cost (ATC)

    • Is described as resembling a large U shape or bowl.

    • The minimum point on the ATC curve is found where it intersects with the marginal cost curve.

  • Average Variable Cost (AVC)

    • Appears almost parallel to the ATC curve.

    • It is essential to indicate the minimum point of the AVC where it is processed correctly, illustrating the cost relationships clearly.


Changes in Cost Curves

  • Forces Affecting Costs:

    • Factors that lead to an increase in costs include:

    • Taxes: Directly affect the cost structure.

    • Input Costs: Increases in the cost of raw materials or labor can lead to higher expenses.

  • Effects on Cost Curves:

    • If costs rise:

    • Both the marginal cost and average total cost curves will shift upward in a parallel manner.

    • Such shifts signify a decrease in the supply of goods since a higher cost typically leads to fewer products being supplied at previous price levels.

    • Example: Rising minimum wage increases labor costs, shifting supply curves upward and decreasing supply.

  • Factors That Decrease Costs:

    • Advancements like new technology can result in reduced operational costs.

    • Example: Amazon's usage of advanced robotics in packaging warehouses can streamline processes and lower costs.

    • Decreases in input costs can also lower overall production costs.


Long Run Production Costs

  • Definition of Long Run:

    • Refers to a time frame where all costs are variable, meaning no fixed inputs or costs exist.

    • In the long run, firms can adjust the scale of their operations, such as increasing or decreasing factory size.

  • Objective in the Long Run:

    • The goal is efficiency in production. Companies aim to minimize costs by selecting the optimal factory size and production method.

  • Envelope Theorem:

    • Represents the concept in economics used to describe the relationship between short-run cost curves and the long-run average total cost curve.

    • While operating with one fixed factor in the short run, firms are limited to a specific average total cost curve determined by current production capacity.

    • In the long run, firms can choose to operate at the most efficient curve based on the number of factories they decide to utilize.


Decision Making in the Long Run

  • Factory Decisions:

    • Firms can choose to operate on variety of average total cost curves depending on the scale of production they decide upon.

    • If the chosen quantity leads to a cost that overlaps with a more efficient curve, firms will opt for the lower-cost setup.

  • Long Run Average Total Cost Curve (LRATC):

    • The LRATC is typically wider than average short-run curves as it reflects the most cost-effective points from various short-run scenarios.

    • Firms should aim to operate at the lowest cost points on the LRATC curve to ensure long-term sustainability and success.


Economies of Scale and Production Costs

  • Three Sections of Long Run Average Total Cost Curve:

    1. Economies of Scale:

    • Occurs as output increases; average total costs decrease.

    • Results from specialization and operational efficiencies.

    • Example: General Electric's dominance in jet engine production due to cost efficiencies defined by larger production scales.

    1. Constant Returns to Scale:

    • When average total costs remain relatively stable as output increases.

    • Balancing effects of increased costs and production efficiencies.

    1. Diseconomies of Scale:

    • A point where further increases in output lead to rising average total costs.

    • Caused by complexity in management and potential communication issues as businesses grow.


Sunk Costs and Their Impact on Decision Making

  • Definition:

    • Sunk costs are costs that have already been incurred and cannot be recovered.

    • Economic theory posits that decisions should disregard sunk costs.

  • Sunk Cost Fallacy:

    • The tendency to continue an endeavor after failing because of already invested resources (time or money).

    • Example: Choosing to stay in a bad movie or job because money or time was already spent, leading to suboptimal future decisions.

  • Real-World Applications:

    • Many students hesitate to switch majors because of previously completed coursework, erroneously thinking they must follow through with their initial choice.


Economies of Scope

  • Definition: This refers to a situation where companies reduce average total costs through the production of a variety of products using similar inputs.

    • Example: General Motors creating multiple car types in a single factory, or Tesla utilizing the same AI technology across various vehicle models.