A bird's view of info‐gap decision theory

Abstract

PurposeThe purpose of this paper is to clarify a number of important facts about info‐gap decision theory.Design/methodology/approachTheorems are put forward to rebut claims made about info‐gap decision theory in papers published in this journal and elsewhere.FindingsInfo‐gap's robustness model is a simple instance of the most famous model in classical decision theory for the treatment of decision problems subject to severe uncertainty, namely Wald's maximin model. This simple instance is the equivalent of the well‐established model known universally as radius of stability. Info‐gap's robustness model has an inherent local orientation. Therefore, it is in principle unable to address the fundamental difficulties presented by the type of severe uncertainty that is postulated by info‐gap decision theory.Practical implicationsThese findings caution against accepting the assertions made in the info‐gap literature about: info‐gap decision theory's role and place in decision making under severe uncertainty; and its ability to model, analyze, and manage severe uncertainty.Originality/valueThis paper exposes the serious difficulties with claims made in papers published in this journal and elsewhere regarding the place and role of info‐gap decision theory in decision theory and its ability to handle severe uncertainty.

Investment decisions under uncertainty—A methodological review on forest science studies

“…Sniedovich (2007) has launched a campaign against IGDT, not seeing the opportunity of IGDT to form a bridge that connects various disciplines. Sniedovich (2007) criticizes IGDT as being only a simple instance of Wald's maximin model and as local by its nature (Sniedovich, 2010). Naturally, that uncertainty set what is searched for by IGDT, i.e.…”

Fooled by local robustness: an applied ecology perspective

“…Details on the relation between info-gap's robustness model, the radius of stability model, and Wald's maximin model, can be found in Sniedovich (2010Sniedovich ( , 2012a. For the purposes of this discussion it suffices to note the following:…”

“…The effects of applying radius of stability models (hence, info-gap's robustness model) in vast uncertainty spaces (which give expression to severe uncertainty) is referred to in Sniedovich (2010Sniedovich ( , 2012a as the No Man's Land effect. This issue is illustrated in Fig.…”

Supporting Fisheries Management by Means of Complex Models: Can We Point out Isles of Robustness in a Sea of Uncertainty?

“…Many limitations of the info-gap approach have been underlined by Sniedovitch [24], [25] and are reviewed in [40]. One of these is that it is performed around a given reference point and therefore is inherently local and not suitable to situations of severe uncertainty.…”

“…The info-gap method has started to permeate ecological modelling, with recent applications to conservation [21]–[23]. However, these practical applications have so far been restricted to rather simple models with analytical solutions and many limitations of this approach have been evidenced [24], [25].…”