A project manager is about to begin estimating the costs of a project and generates the work breakdown structure. Because of the nature of the work packages, the time and cost estimates are highly uncertain.

The ratio method involves using historical data to derive cost estimates based on established ratios, which assumes a level of certainty and predictability in project costs. However, in this case, the high uncertainty of the work packages makes reliance on fixed ratios inappropriate, as they do not account for variability.

The consensus method relies on input from multiple stakeholders or experts to generate cost estimates. While this can provide valuable insights, it may not adequately address the high uncertainty present in the work packages, as varying opinions may lead to unclear or overly optimistic cost projections.

Apportionment involves distributing the overall project budget based on predefined percentages for each work package. This method assumes a more stable cost structure and does not effectively capture the uncertainties associated with the specific work packages. Thus, it may result in inaccurate estimates when faced with high variability.