Analysis of cost behaviour : Tillie Makris, works in the cost-estimating department of Byndham Hotels and Resorts, a large chain of international hotels. Her job is to develop cost functions for the various products and services provided by Byndham. She does this by meeting with supervisors and managers who operate the processes that provide the products and services. This is because these individuals know the most about the processes and the behaviours of those costs.

Explain which cost estimation method is used by Byndham Hotels and Resorts.