out of sample definition

Question

Can anyone explain the difference between “in-sample” and “out-of-sample” forecasts?

Answer 1

It is statistics speak which in most cases means "using past data to make forecasts of the future". "In sample" refers to the data that you have, and "out of sample" to the data you don't have but want to forecast or estimate.

Answer 2

The data points used to build the model constitute in sample data where as all the new data points not belonging to the training sample constitute out of sample data.