Learn in the textbookEstimating Development Effort
DefinitionAnalogy-based estimation (類推見積法) estimates size and effort from the actual results of past projects that resemble the development about to begin.
ExplanationThe actual size, effort and cost of a similar project serve as the yardstick, and the figures are inferred after adjusting for how this project differs. It gives a rough estimate quickly, even before the details are settled. On the other hand, for a new kind of development with no similar precedent, the basis for the estimate itself becomes weak.
AnalogyIt is like looking at what a similar trip cost you last year to get a rough idea of this year's travel budget.
Memory hookIn the Japanese name, 類 means "similar" and 推 means "infer": the method infers from similar precedents.