Leads and lags

Leads and Lags are a way to track changes in one thing's behavior when something else changes. For example, if the price of apples goes up, the demand for oranges could go up or down. This is called a lead-lag relationship. A lead means that when the price of apples changes, the demand for oranges changes a bit later. A lag means that when the price of apples changes, the demand for oranges changes a bit sooner. So by tracking the lead-lag relationship, you can predict what might happen when the price of apples changes.