Variable(redirected from Undefined variable)
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An element in a model. For example, in the model RS&Pt+1 = a + b Tbill t + et, where RS&Pt+1 is the return on the S&P in month t+1 and Tbill is the Tbill return at month t, both RS&P and Tbill are "variables" because they change through time; i.e., they are not constant.
Anything that does not have a set value. In basic algebra, a variable is often expressed as "x." Variables in economics and finance may be measures such as GDP, prices, or interest rates. Analysts use complicated equations to determine the value of some variables at the present time and even more complicated equations to predict their possible future values. See also: Regression.