month, holiday indicator Invoice Date -> Day of the week, month, holiday indicator, number of unpaid invoices to date Order Date, Invoice Date -> number of days between Order and Invoice Supplier ID -> average order amount, average number of order per year, size of the supplier, revenue of the supplier Budget Code -> average number of order per year, % of budget Buyer Id -> average number of order per year
train / test split : bulk supplier payments makes the model performance over optimistic Supplier ID Invoice Date Payment Date S921 20/02/2013 31/03/2013 S921 20/02/2013 31/03/2013 S921 20/02/2013 31/03/2013 Supplier ID Invoice Date Payment Date S921 20/02/2013 31/03/2013 S921 20/02/2013 31/03/2013 Supplier ID Invoice Date Payment Date S921 20/02/2013 31/03/2013 Train Test Test set contains observations already seen in train set. This is cheating ...