Flight Delay

Mia started her new job with one of the best airlines in the country.

Her first project is to build a supervised learning model to predict flight delays. She has access to a large dataset containing information about her airline's arrival and departure flights.

Early on, Mia discovered something interesting: a delayed flight impacts every flight that day. Any future flight on the same day will likely depart late when a delay occurs.

Mia wants to split her dataset into a training and a test set. How would you recommend she does it?