Introduction to the Demand for Labour
Welcome! In this chapter, we are looking at the "other side" of the job market. Usually, when we think of demand, we think of ourselves buying clothes or food. But in the labour market, firms (employers) are the ones doing the demanding. They "buy" your time and skills. Understanding why a firm chooses to hire one more worker—or why they might fire someone—is key to understanding wages and employment levels in the real world. Don't worry if it seems a bit backwards at first; just remember: Firms demand labour, and workers supply it.1. Derived Demand
One of the most important things to remember is that labour is a derived demand. This means that a firm doesn't want workers just for the sake of having them; they only want workers because there is a demand for the goods or services those workers produce. Example: A construction company doesn't hire bricklayers because they like having people on a building site. They hire them because people want to buy new houses. If the demand for new houses crashes, the demand for bricklayers will also crash. Quick Review: If demand for the final product goes up, the demand for labour goes up. If demand for the product falls, fewer workers are needed.2. Marginal Revenue Product (MRP) Theory
How does a boss decide exactly how many people to hire? They use MRP Theory. This theory suggests that a firm will hire a worker as long as that worker adds more to the firm's revenue than they cost in wages.The Formula:
To find the Marginal Revenue Product (MRP), we use this calculation: \( MRP = MPP \times MR \) Where: • MPP (Marginal Physical Product): The extra physical output one additional worker produces (e.g., how many extra pizzas they make). • MR (Marginal Revenue): The extra money the firm gets from selling one more unit of that output.The Hiring Rule:
A rational, profit-maximising firm will continue to hire more workers as long as the MRP is greater than the wage rate. They stop hiring when: \( MRP = \text{Wage} \)Why does the Demand Curve slope downwards?
In a diagram, the Demand for Labour curve is the MRP curve. It slopes downwards because of the Law of Diminishing Marginal Returns. As you add more workers to a fixed amount of capital (like a kitchen with only two ovens), each extra worker eventually adds less to total output than the worker before them. Did you know? Even a "superstar" worker might have a low MRP if the firm's equipment is bad. A world-class chef can't produce much if the stove is broken!3. Factors Affecting the Demand for Labour
The demand for labour isn't fixed; the whole curve can shift to the left (decrease) or right (increase). Here is what causes those shifts: • Changes in Productivity: If workers become more efficient (higher MPP) through better training or better technology, their MRP rises, and firms will demand more of them. • Changes in the Price of the Product: If the price of the good the workers make rises (higher MR), each worker is suddenly "worth" more to the firm, even if they aren't working any harder. • The Price of Capital (Substitutes): If robots or software become cheaper, a firm might demand fewer human workers and "shift" to machines. • Non-Wage Labour Costs: If the government increases the taxes a firm has to pay for every employee (like National Insurance), the demand for labour will fall. Key Takeaway: The demand for labour increases if workers produce more, if the product becomes more expensive, or if the costs of hiring (other than wages) go down.4. Productivity and Unit Labour Costs
Firms are very interested in Unit Labour Costs. This is the average cost of labour per unit of output produced.The Relationship:
• If Productivity (output per worker) increases faster than Wages, then Unit Labour Costs will fall. • This makes a firm (and a country) more competitive because they can sell their goods at a lower price while still making a profit.Quick Tip: Don't confuse Total Labour Costs (the whole wage bill) with Unit Labour Costs (the cost of the labour inside a single product).
5. Wage Elasticity of Demand for Labour (WEDL)
Wage Elasticity of Demand measures how much the quantity of labour demanded changes when the wage rate changes. • Elastic Demand: A small increase in wages leads to a large drop in the number of workers hired. • Inelastic Demand: A large increase in wages leads to only a tiny drop in the number of workers hired.What determines Elasticity? (Memory Aid: S.E.L.T)
You can remember these factors using the acronym SELT: 1. S - Substitutability: Can the worker be easily replaced by a machine? If yes, demand is elastic. 2. E - Elasticity of product demand: If the firm's customers are very sensitive to price (elastic product demand), the firm can't pass on higher wage costs to them. Therefore, labour demand will be elastic. 3. L - Labour cost as a % of total costs: If wages are a huge part of total costs (like in a cleaning company), demand for labour is elastic. If they are a tiny part (like a law firm's receptionist), demand is inelastic. 4. T - Time: In the long run, it is easier for firms to find ways to replace workers with machines, so demand becomes more elastic over time.Common Mistakes to Avoid
• Mistaking the "Demander": Students often say "I am demanding a job." In Economics, you are supplying your labour. The firm is the one demanding it. • Forgetting Diminishing Returns: Don't forget that the MRP curve slopes down because of physical limits (MPP), not just because the firm wants to pay less. • Ignoring the "Derived" aspect: When writing an essay, always link labour demand back to the demand for the actual product being made.Summary Checklist
✔ Derived Demand: Labour demand comes from product demand.✔ MRP = MPP x MR: This is how firms calculate a worker's value.
✔ The Hiring Rule: Hire until Wage = MRP.
✔ Shifts: Caused by productivity, product price, or costs of substitutes.
✔ Elasticity: Depends on how easy it is to replace a human with a machine (Substitutability) and how much of the total cost labour represents.