Parametric procedures can be powerful tools for making informed estimates. However, they require careful data collection, model development, and validation to ensure their reliability. It's also important to complement parametric procedures with expert judgment and risk assessment for more comprehensive project estimation.
Ratio methods or parametric estimation techniques are valuable tools for IT project managers to make informed estimates based on historical data and quantitative relationships. However, they should be used with caution, considering the similarity between the current project and the historical data used, and supplemented with expert judgment when necessary to enhance accuracy and reliability.