1. Copyright © 2008 Pearson Addison-Wesley. All rights reserved. Chapter 7 Producers in the Short Run

2. Copyright © 2008 Pearson Addison-Wesley. All rights reserved. 7-2 In this chapter you will learn to 1. Describe the various forms of business organizations and the different ways that firms can be financed. 2. Explain the difference between accounting profits and economic profits. 3. Describe the relationships between total product, average product, and marginal product, and the law of diminishing marginal returns. 4. Explain the difference between fixed and variable costs, and the relationships between total costs, average costs, and marginal costs.

3. Copyright © 2008 Pearson Addison-Wesley. All rights reserved. 7-3 Organization of Firms Firms come in six basic types: 1.Single proprietorships 2.Ordinary partnerships 3.Limited partnerships 4.Corporations 5.State-owned enterprises 6.Non-profit organizations Some firms are multinational enterprises (MNEs), which operate in more than one country. What are Firms?

4. Copyright © 2008 Pearson Addison-Wesley. All rights reserved. 7-4 Firms use financial capital -- equity and debt. A firm acquires funds from its owners in return for stocks, shares, or equity. Profits may be distributed as dividends, or may be retained. A firm’s creditors are lenders -- using debt instruments (loans, bonds and securities in money markets). Financing of Firms APPLYING ECONOMIC CONCEPTS 7.1 Kinds of Debt Instruments

5. Copyright © 2008 Pearson Addison-Wesley. All rights reserved. 7-5 Goals of Firms Economists usually make two key assumptions about firms: 1.firms are assumed to be profit-maximizers 2.each firm is assumed to be a single, consistent, decision-making unit Based on these assumptions, economists can predict the behavior of firms in various situations.

6. Copyright © 2008 Pearson Addison-Wesley. All rights reserved. 7-6 Production, Costs, and Profits Production Firms use four types of inputs for production: 1. Intermediate products 2. Inputs provided directly by nature 3. Inputs provided directly by people, such as labor services 4. Inputs provided by the services of physical capital (machines)

7. Copyright © 2008 Pearson Addison-Wesley. All rights reserved. 7-7 APPLYING ECONOMIC CONCEPTS 7.2 Is It Socially Responsible to Maximize Profits? Profits

8. Copyright © 2008 Pearson Addison-Wesley. All rights reserved. 7-8 The production function relates inputs to outputs. It describes the technological relationship between the inputs that a firm uses and the output that it produces. Remember that production is a flow: it is a number of units per period of time. In simple functional notation we have: Q = f(L,K) Production Function

9. Copyright © 2008 Pearson Addison-Wesley. All rights reserved. 7-9 Costs and Profits Economic profit includes both implicit and explicit costs. Implicit costs include the opportunity cost of the owner’s time and capital. Accounting Profits = Revenues – Explicit Costs Economic profit includes both implicit and explicit costs. Economic Profits = Accounting Profits – Implicit Costs

10. Copyright © 2008 Pearson Addison-Wesley. All rights reserved. 7-10 Economic Profits Economic profit is sometimes called pure profit. If economic profit is positive, then the owner’s capital is earning more than it could in its next best alternative use. Economic Profit is the difference between revenues received from the sale of output and the opportunity cost of the inputs used to make the output. Negative economic profits are called economic losses.

11. Copyright © 2008 Pearson Addison-Wesley. All rights reserved. 7-11 Table 7.1 Accounting versus Economic Profit for Ruthie’s Gourmet Soup Company

12. Copyright © 2008 Pearson Addison-Wesley. All rights reserved. 7-12 Profits and Resource Allocation Economic profits and losses play a crucial signaling role in the workings of a free-market system. If firms are incurring economic losses, the industry’s resources are more highly valued in other uses, and owners of the resources will move them to those other uses. Owners of factors of production move resources into industry that make profits.

13. Copyright © 2008 Pearson Addison-Wesley. All rights reserved. 7-13 Profit-Maximizing Output A firm’s (economic) profit is equal to total revenues minus total (economic) costs:  = TR - TC What happens to profits as output changes depends on what happens to both revenues and costs.

14. Copyright © 2008 Pearson Addison-Wesley. All rights reserved. 7-14 Time Horizons for Decision Making The short run is a period of time in which some of the firm’s factors of production are fixed - typically capital is fixed in the short run Fixed factor – An input whose quantity cannot be changed in the short run. Variable factor – An input whose quantity can be changed over the time period under consideration.

15. Copyright © 2008 Pearson Addison-Wesley. All rights reserved. 7-15 The Long Run The long run is the length of time over which all of the firm’s factors of production can be varied, but its technology is fixed. The very long run is the length of time over which all the firm’s factors of production and its technological possibilities can change.

16. Copyright © 2008 Pearson Addison-Wesley. All rights reserved. 7-16 Production in the short run Total, Average, and Marginal Products Total product (TP) is the total amount of output that is produced during a given period of time. Average product (AP) is the total product divided by the number of units of the variable factor used to produce it (usually thought of as labor): AP = TP / L

17. Copyright © 2008 Pearson Addison-Wesley. All rights reserved. 7-17 Figure 7.1 Total, Average, and Marginal Products in the Short Run

18. Copyright © 2008 Pearson Addison-Wesley. All rights reserved. 7-18 Diminishing Marginal Product The law of diminishing returns: As more workers are added to a production process, each can specialize on one task, and the workers’ marginal product initially rises. But if there is a fixed amount of physical capital, eventually the marginal product is likely to fall. APPLYING ECONOMIC CONCEPTS 7.3 Three Examples of Diminishing Returns

19. Copyright © 2008 Pearson Addison-Wesley. All rights reserved. 7-19 The Average–Marginal Relationship The AP curve slopes upward as long as the MP curve is above it (and AP slopes downward when MP is below it). If an additional worker’s output raises the average product, the MP must exceed AP. Similarly, if the marginal worker’s output reduces the average product, the MP must be less than the AP. It follows that the MP curve must intersect the AP curve at its maximum point.`

20. Copyright © 2008 Pearson Addison-Wesley. All rights reserved. 7-20 Costs in the Short Run Defining Short-Run Costs TC = TFC + TVC ATC = AFC + AVC Total Cost Total Fixed Cost Total Variable Cost Average Total Cost Average Fixed Cost Average Variable Cost

21. Copyright © 2008 Pearson Addison-Wesley. All rights reserved. 7-21 Marginal cost (MC) is the increase in total cost resulting from increasing the output by one unit. Because fixed costs do not vary with output, the only part of TC that changes is the variable cost. MC =  TC QQ Costs in the Short Run

22. Copyright © 2008 Pearson Addison-Wesley. All rights reserved. 7-22 Table 7.2 Short-Run Costs: Fixed Capital and Variable Labor

23. Copyright © 2008 Pearson Addison-Wesley. All rights reserved. 7-23 Figure 7.2 Total, Average, and Marginal Cost Curves ATC = AVC + AFC (a vertical summation) AFC declines steadily as output rises — this is called spreading the overhead.

24. Copyright © 2008 Pearson Addison-Wesley. All rights reserved. 7-24 The shape of the ATC curve? falling AFC tends to push down ATC rising MC (and thus AVC) tends to push up ATC at some point the second effect overcomes the first effect and ATC begins to rise ATC MC AVC AFC Output Cost Short-Run Cost Curves

25. Copyright © 2008 Pearson Addison-Wesley. All rights reserved. 7-25 Why U-Shaped Cost Curves? Eventually diminishing AP of the variable factor implies eventually rising AVC. AVC is at its minimum when AP reaches its maximum. Eventually diminishing MP of the variable factor implies eventually rising MC. MC reaches its minimum when MP reaches its maximum. Key idea: Each additional worker adds the same amount to total cost but a different amount to total output.

26. Copyright © 2008 Pearson Addison-Wesley. All rights reserved. 7-26 Capacity The level of output that corresponds to the minimum short-run ATC is the capacity of the firm. Capacity is the largest output that can be produced without encountering rising average cost per unit. A firm that is producing at an output less than the point of minimum ATC is said to have excess capacity.

27. Copyright © 2008 Pearson Addison-Wesley. All rights reserved. 7-27 Figure 7.3 An Increase in Variable Input Prices