Meaningful calculations of risk
From one point of view, it's tempting to boil estimates down to a figure. "It'll take three days" is easy to plan with. However, treating estimates as firm commitments is risky. How risky? It depends.
From another point of view, giving estimates is taking a risk, too. For example, a contractor giving a quote to a potential client might be tempted to give an optimistic estimate. How much risk is involved? Again - it depends.
Estigator calculates probabilities. This helps stakeholders visualise, quantify and have meaningful discussions about the risk inherent in estimates.
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Do sums with uncertainties
Estimation usually gets easier if it can break it down as a sum of smaller parts. Adding up a series of estimates and getting a total... that part's easy. Crucially, Estigator tells you about distributions as well.