1.3 - Objectives of Economic Agents
The concept of the margin in economics
The margin refers to the extra effect resulting from a small increase in one factor, such as producing or consuming one more unit.
Marginal changes
A marginal change measures the impact on one variable when another variable increases by a single unit. For example, marginal cost represents the extra expense involved in manufacturing one additional item. Marginal concepts help explain various economic ideas, including how prices are set, why wages differ between jobs, the effects of externalities, the output level that maximises profit in competitive markets, and how efficient different market structures are.
Key marginal concepts
- Marginal product (MP) - The additional output produced by using one more unit of input, such as labour.
- Marginal revenue (MR) - The extra income gained from selling one more unit of a product.
- Marginal tax rate - The rate of tax applied to an additional unit of income.
Formula for marginal cost
Where:
- Total cost at new output level = Overall cost of producing the higher quantity (£)
- Total cost at previous output level = Overall cost of producing one unit less (£)
Worked example - Calculating marginal cost
A bakery's total cost for producing 200 loaves is £300, and the total cost for 201 loaves is £304. Calculate the marginal cost of the 201st loaf.
Step 1: Identify the values
- Total cost at 201 loaves = £304
- Total cost at 200 loaves = £300
Step 2: Apply the marginal cost formula
Step 3: Interpretation
The marginal cost of £4 shows the extra expense for producing one more loaf, which helps the bakery decide on output levels.
Marginal utility and consumer rationality
Consumers make choices based on the additional benefits they gain from goods, aiming to get the most satisfaction from their spending. This behaviour follows traditional economic ideas about rational decision-making.
Understanding utility in consumption
Marginal utility is the extra satisfaction obtained from using one more unit of a product or service. Total utility is the complete satisfaction derived from all units of a product consumed.
The law of diminishing marginal utility:
- As more units are consumed, the additional satisfaction from each extra unit decreases.
- Rational consumers continue buying until the marginal utility equals the price of the item, balancing benefit with cost.
- This diminishing effect explains why demand curves slope downwards: as price falls, consumers are willing to buy more because the marginal utility still matches or exceeds the lower price.
Example of diminishing marginal utility
Consider a consumer buying drinks on a hot day:
- The first drink provides high marginal utility, worth paying £2.
- The second offers less utility, worth only £1.50.
- By the third, utility drops further, so the consumer might pay just £1.
This pattern shows why people buy less at higher prices and more at lower ones.
Objectives of producers and firms
Firms, as key economic agents, focus on goals that ensure their long-term success. Traditional economics assumes they act rationally to achieve the highest possible benefits.
Primary objective: Profit maximisation
Profit is calculated as total revenue minus total costs. Firms aim to maximise profit for several reasons:
- It supports ongoing operations and survival in competitive markets.
- It provides returns to owners and shareholders, as well as incentives like bonuses to employees.
- It allows reinvestment in areas such as new equipment or expansion to drive future growth.
Alternative objectives for firms
While profit is central, firms may pursue other goals depending on their size, market position, or values:
- Sales or market share maximisation - Increasing sales volume or capturing a larger portion of the market can build dominance and potentially lead to monopoly power.
- Prestige and stability - Growing into a large organisation enhances reputation and reduces vulnerability to economic shocks.
- Ethical goals - Some firms prioritise social responsibility, such as supporting environmental causes or fair trade practices, even if it means lower short-term profits.
Objectives of consumers and governments
Different economic agents have unique goals, but all aim to maximise their overall benefits rationally within their constraints. Consumers and governments balance personal or public needs against available resources.
Consumer objectives
Consumers seek to maximise their utility, or satisfaction, from goods and services while managing limited budgets. Utility differs between people; for some, it means security, while for others, it involves leisure or experiences.
How consumers maximise utility:
- They make rational choices to increase utility, such as selecting products that offer the best value.
- As workers, consumers aim to maximise earnings while preserving time for personal activities, striking a balance between income and leisure.
Government objectives
Governments work to allocate scarce resources to meet the needs and desires of the population, focusing on the broader public interest.
Key government objectives:
- Economic growth - Increasing the economy's output, often measured by gross domestic product (GDP), to improve living standards.
- Full employment - Ensuring as many people as possible have jobs to reduce unemployment and support economic stability.
- Balance of payments equilibrium - Maintaining a balance between exports and imports to avoid deficits or surpluses that could harm the economy.
- Low inflation - Keeping price rises under control to preserve purchasing power and economic confidence.
These goals can conflict; for example, pursuing rapid growth might lead to higher inflation.
Role of marginal concepts in economic decision-making
Economic theory views people and organisations as utility maximisers who base choices on small, incremental changes rather than overall totals. This approach assumes rational behaviour focused solely on achieving the greatest possible benefit.
How marginal thinking influences decisions
Decisions are made by comparing the extra benefits (like marginal utility or revenue) against the extra costs (such as marginal cost). For consumers, this means buying until marginal utility matches price, ensuring efficient use of money. For producers, it involves producing until marginal revenue equals marginal cost, which maximises profit. Overall, marginal analysis helps agents respond to changes, such as adjusting output or consumption in response to price shifts, leading to more effective resource allocation.