Think of a small town where there is only one big factory 🏭 that hires all the workers. Because the factory is the only employer, it has a lot of power over the wages it offers. This situation is called a monopsony – a market where there is only one buyer of labour.
In a normal competitive market, the wage is set where the value of an extra worker’s output (the marginal revenue product, MRPL) equals the wage. In a monopsony, the employer must pay a higher wage to attract more workers, so the marginal cost of labour (MCL) rises with each additional worker.
Because the MCL is higher than the wage, the monopsonist hires fewer workers at a lower wage than would be the case in competition:
Result: Lower employment and lower wages for workers.
Imagine a graph with Employment (E) on the x‑axis and Wage (W) on the y‑axis.
In a competitive market, the intersection of demand and supply would be higher on the y‑axis (higher wage) and further right on the x‑axis (higher employment).
In the town of Greenfield, the Greenfield Factory is the only employer of 200 workers. Let’s see how a minimum wage changes things.
| Scenario | Wage ($/hour) | Employment (workers) |
|---|---|---|
| Monopsony (no minimum wage) | $12 | 120 |
| With Minimum Wage of $15 | $15 | 180 |
After the minimum wage, the factory hires more workers and pays a higher wage, improving overall welfare in Greenfield.