Randannahmen

Randannahmen is a term used in German-language methodological discourse to describe assumptions about the margins or extremes of a model, dataset, or argument. The exact usage varies, but it generally refers to stipulations about boundary conditions, tail behavior, or rare events that lie outside the central, well-sampled region of analysis. The word combines Rand (edge, margin) with Annahmen (assumptions), signaling a focus on what happens at the periphery of the considered scope.

Definition and scope. Randannahmen are not a single, fixed concept but a family of assumptions that specify how a system behaves under extreme or uncommon conditions. They can concern statistical tails, boundary values in equations, or scenario parameters chosen to test robustness. In practice, Randannahmen aim to reveal whether conclusions hold when standard data or typical cases are insufficient to determine outcomes.

Applications. In statistics and risk assessment, Randannahmen may involve exploring tail risks, stress-testing, or extrapolating beyond observed data. In engineering and design, they relate to boundary conditions and safety margins that ensure functionality under unlikely but possible scenarios. In policy analysis, Randannahmen can shape evaluations by considering extreme but plausible developments, helping to assess resilience or vulnerability.

Relation to other concepts. Randannahmen are related to sensitivity analyses, scenario planning, and robustness checks, but they emphasize the edge cases rather than typical conditions. They can be controversial if used to selectively justify conclusions by focusing on favorable margins.

Criticism and considerations. Critics warn that Randannahmen may introduce bias if margins are chosen strategically, reduce falsifiability, or overstate uncertainty. Transparency about the rationale for edge-case assumptions and accompanying uncertainty analyses are typically recommended.

See also: boundary conditions, tail risk, scenario analysis, sensitivity analysis, robustness checks.