Which one of the following statements about forecasting is false?

Causal methods of forecasting use historical data on independent variables $($promotional campaigns, competitors' actions, etc.$)$ to predict demand.

Three general types of forecasting techniques are used for demand forecasting: time$-$series analysis, causal methods, and judgment methods.

Time series express the relationship between the factor to be forecast and related factors such as promotional campaigns, economic conditions, and competitor actions.

A time series is a list of repeated observations of a phenomenon, such as demand, arranged in the order in which they actually occurred.