Production and Cost Theory

PRODUCTION AND COST THEORY

Course Information

  • Course Code: MBC3563 Economics 1

  • Institution: Tan Chiang Ching School of Business and Management, University of Technology Sarawak (UTS), 96000 Sibu, Sarawak

Learning Outcomes

By the end of this lesson, students should be able to:

  • Describe the classification of factors of production.

  • Explain the law of diminishing marginal returns.

  • Describe several concepts of costs.

  • Explain the curves of short-run costs.

  • Relate the various measures of short-run costs with the long-run costs and their differences.

  • Evaluate why the long-run average costs curve has a U-shape.

Theory of Production

Definition of Production

  • Production: The process of using factors of production to produce goods and services, transforming inputs into outputs.

    • Outputs: Finished products resulting from the production process.

    • Inputs: Factors of production that a firm uses in the production process.

Factors of Production

  • Definition: Goods and services that assist in the production process, also known as inputs.

  • Economists may interchangeably use the term ‘input’ for ‘factors’ in the context of production.

Classification of Factors of Production

  1. Land: All natural resources or gifts of nature.

  2. Labour: Physical or mental activities performed by human beings.

  3. Capital: Man-made wealth used for further production.

  4. Entrepreneur: An individual who combines various factors of production to initiate the production process and bears the associated risks.

Production Function

Definition

  • Production Function: A statement of the relationship between inputs (factors of production) and outputs (goods and services) that shows the maximum output that can be produced with given inputs.

    • Notation:

    • $Q$ = Quantity of Output

    • $K$ = Capital

    • $L$ = Labour

    • $M$ = Raw Material

    • Functional Representation: $Q = f(K, L, M, ext{etc.})$

Short Run vs. Long Run Production Functions

  • Short Run: A period where at least one input is fixed, while others may vary.

  • Long Run: A period in which all inputs are variable; firms can adjust inputs to increase output.

Factor Inputs

  1. Fixed Input: An input whose quantity does not change with the output level (e.g., machinery, land, buildings).

  2. Variable Input: An input whose quantity changes with the level of output (e.g., raw materials, electricity).

Short Run Production Function

The production function in the short run can be represented as:

  • $Q = f(K, L)$ (where $L$ is the variable input and $K$ is the fixed input)

Concepts in Short-Run Production Function

Total Product (TP)

  • Total Product (TP): Total output produced when a given quantity of a variable input is used along with fixed inputs.

Average Product (AP)

  • Average Product (AP): Average output produced per unit of variable input used. Defined as:

    • $APL = rac{TP}{L}$ (where $L$ is the quantity of labour used)

Marginal Product (MP)

  • Marginal Product (MP): The additional output generated by adding one more unit of input, while keeping other inputs constant. Defined as:

    • $MPL = rac{igtriangleup TP}{igtriangleup L}$ (change in total product due to change in labour)

Tables and Figures

Table 1: Total Product, Marginal Product, and Average Product

Capital

Labour

TP

APL

MPL

1

0

0

1

1

1

1

3

3

3

1

2

8

4

5

1

3

12

4

4

1

4

15

3.75

3

1

5

17

3.4

2

1

6

17

2.83

0

1

7

16

2.29

-1

1

8

13

1.63

-3

Figure 1: Relationship Between TP and MP

  • When MP is increasing, TP increases at an increasing rate.

  • When MP is decreasing, TP increases at a decreasing rate.

  • When MP is zero, TP is at its maximum.

  • When MP is negative, TP declines.

Figure 1: Relationship Between AP and MP

  • When MP is above AP, AP is increasing.

  • When MP is below AP, AP is decreasing.

  • When MP equals AP, AP is at maximum.

Stages of Production

  • Stage I: Increasing Returns

    • Begins with the first use of labour until it reaches maximum AP. Both MP and AP are positive. Rational producers do not operate at this level because AP can always be increased.

  • Stage II: Diminishing Returns

    • Occurs between maximum AP and when MPL is zero. Both MP and AP remain positive, but MP is less than AP, causing AP to decrease. Producers broadly operate in this stage.

  • Stage III: Negative Returns

    • Characterized by negative MPL and decreasing total product, rational producers do not operate in this stage.

The Law of Diminishing Returns

  • Definition: The law states that as more units of a variable input are added to a fixed input, the marginal product and average product of the variable input will eventually decrease.

Figure 2: Total, Average and Marginal Product Curves

  • Graphical representation of Total Product, Average Product, and Marginal Product, illustrating the points of diminishing returns.

Long Run Production Function

  • In the long run, all inputs are variable, enabling firms to optimize production cost through better input combinations, production scale, technology, and location decisions.

  • Inputs-output relationships can be modeled using isoquants.

Cost of Production

Definition of Costs

  • Costs: Economic resources exchanged or sacrificed to obtain something in return.

    • Costs can manifest in money, goods, or time.

The Firm’s Objective

  • Economic goal: Maximize profits.

Economic vs. Accounting Profits

  • Profit: Difference between Total Revenue (TR) and Total Cost (TC).

  • Accounting Profit: Calculated by accountants considering only explicit costs.

  • Economic Profit: Considers both explicit and implicit costs; implicitly includes opportunity costs.

Explicit Costs vs. Implicit Costs

  • Explicit Costs: Direct monetary outlay for inputs purchased.

  • Implicit Costs: Imputed costs for inputs owned by the producer (no direct payment).

Example of Profit Calculation

  • Alvin's Example: Comparison of economic profits vs. accounting profits considering his business decision.

  • Table 1: Breakdown of economic profits vs. accounting profits

    • Total Revenue: RM 120,000

    • Explicit Costs: RM 64,000

    • Accounting Profit: RM 56,000

    • Implicit Costs: RM 20,000

    • Economic Profit: RM 36,000

Total Revenue, Total Cost, and Profit

  • Total Revenue: Amount received from output sales.

  • Total Cost: Economic cost associated with inputs used in production.

  • Profit: Defined as:

    • Profit = Total Revenue - Total Cost

Short-Run Production Costs

Cost Definitions

  • Fixed Costs (FC): Costs that do not change with output level.

  • Variable Costs (VC): Costs that change with output level.

Total Cost Calculation

  • Total Cost (TC): Sum of fixed costs and variable costs.

    • Equation:

    • TC = FC + VC

    • VC = TC - FC

Table 2: Total Cost, Fixed Cost, and Variable Cost

  • Outputs, Fixed Costs, Variable Costs, and Total Costs documented.

Average Costs

  • Average Fixed Cost (AFC): Calculated as AFC = rac{FC}{Q}

  • Average Variable Cost (AVC): Calculated as AVC = rac{VC}{Q}

  • Total Average Cost (AC): Calculated as AC = rac{TC}{Q} or AC = AFC + AVC

Marginal Cost (MC)

  • Defined as the added cost due to the production of one more unit.

  • Formulated as:

    • MC = rac{igtriangleup TC}{igtriangleup Q}

Tables and Figures

Table 3: Total Costs, Average Costs, and Marginal Costs

  • Structured to show outputs, fixed costs, variable costs, total costs, average costs, and marginal costs.

Figure 4: Average Cost and Marginal Cost Curves

  • Demonstrates the relationship between average cost and marginal cost.

Average Cost Behavior

  • Average fixed cost (AFC) declines but does not reach zero.

  • Average variable cost (AVC) faces increase due to diminishing returns.

  • U-shaped curves for average cost due to interplay of AFC and AVC.

Relationship between Marginal Cost and Average Total Cost

  • Marginal Cost (MC) impacts Average Cost (AC) such that:

    • When MC is less than AC, AC falls.

    • When MC is greater than AC, AC rises.

  • MC intersects AC at its minimum point, impacting average costs in production decisions.

Typical Cost Curves

Properties of Cost Curves

  • MC rises eventually with output.

  • Average total cost curve appears U-shaped.

  • MC intersects average total cost curve at its minimum.

Relationship between Production and Short-Run Costs

  • Cost curves are linked to product curves:

    • Minimum MC coincides with maximum MP.

    • Minimum AVC aligns with maximum AP.

Differences Between Long-Run and Short-Run Costs

  • Long-run costs have no fixed costs: TC = VC.

  • Diminishing marginal returns do not apply in the long run.

Implications for Producers

  • Producers cannot build facilities tandem with the long-run average costs curve (LRAC).

  • Planning in the long-run involves decisions on adjustments according to product demand shifts.

Figure 6: Long-Run Average Cost Curves

  • Representation of short-run average cost (SRAC) against long-run average cost (LRAC).

Economies and Diseconomies of Scale

Economies of Scale

  • Reduction of long-run average total cost with increased output.

  • Factors affecting economies of scale include:

    • Labour specialization.

    • Efficient management.

    • Equipment usage efficiency.

    • Technical improvements in production.

Diseconomies of Scale

  • Increases in long-run average total cost with output, caused by:

    • Management complexity in large firms.

    • Labour issues such as disinterest and decreased productivity.

Constant Returns to Scale

  • Occur when production increases proportionately with inputs.

  • Seen in horizontal LRAC.

Conclusion

  • Overview of concepts related to production and costs, elucidating their fundamental importance in economics and business decision-making strategies.

Thank You

To aid in remembering the key concepts of Production and Cost Theory, we can use the acronym P.L.C.E.C.E. Each letter stands for a main idea:

  • P: Production - The process of transforming inputs into outputs.

  • L: Labour - The human effort involved in production.

  • C: Capital - The tools and machinery utilized in the production process.

  • E: Entrepreneur - The individual who organizes and combines resources.

  • C: Costs - Consists of fixed costs that do not change with output and variable costs that fluctuate with production levels.

  • E: Economies of Scale - The reduction in costs as production increases.
    Using this acronym, students can easily recall the foundational elements of production and cost theory for better understanding and retention.