Question

In the labor market, what causes a movement along the demand curve? What causes a shift in the demand curve?

Short answer

Change in wages or salaries leads to movement along the labor demand curve. Change in factors other than wages or salaries leads to shift of the labor demand curve.

Step-by-step solution

Labor Market Basic Concept 

Labor Market demand is done by firms. This demand is called Derived Demand, based on demand of the good produced by respective labor.

Primary factor effecting quantity of labor demanded is its price ie wages & salaries, and it former is inversely related to latter.

Detailed Explanation - Movement & Shift 

Labour demand curve is a downward sloping curve showing quantity of labor demanded at various wages or salaries level.

Change in wages or salaries causes increase (expansion) or decrease (contraction) in 'quantity demanded' of labor, which leads to movement along the labor demand curve.

Change in any factor other than wages or salaries (for eg - change in demand of good produced by that labor or change in technology of production) causes increase or decrease in 'demand' of labor, which lead to shift of the labor demand curve.