Speculation and reasonableness: a non-Bayesian theory of rationality

Whither Keynesian probability? Impolite techniques for decision-making

“…As a matter of fact, Keynes came to reject the idea that probability functions are always well-defined, a viewpoint revived by some recent criticism of the Bayesian mainstream (Gilboa et al 2008, Binmore 2009). This section aims to show in which sense Keynes's critique 8 That reasonableness can be viewed as Keynes's notion of rationality applied to an environment in which numerical probabilities are not available, but there is evidence on which to act, has been argued by Carabelli (2002). 9 The Post Keynesian contention, that uncertainty is irreducible to calculus, often rests on an understanding of uncertainty that concentrates on the ontology of the economic domain, where novelty is not foreseeable ex-ante even in principle (Lawson 1985).…”

“…As noted byCarabelli (2002), on this ground there is a significant continuity between Keynes's 1910 lectures on speculation and his analysis of financial markets in Chapter 12 of the GT.…”

“…The viewpoint presented here partly overlaps with Keynesian interpreters like Gerrard (1994Gerrard ( , 2003 and Runde (1994aRunde ( , 2001, who discuss the relevance of Keynes's work for a critique of Bayesian decision-making. Elements of this view can also be found in Carabelli (2002) and Carabelli and Cedrini (2013), where the significance of "reasonable", as opposed to "rational" judgement is examined. However, the crucial interpretative point put forward in the present paper consists of an inspection of decision criteria for Keynesian decision-making under uncertainty that is not made in the literature just quoted.…”

On the relationship between Keynes’s conception of evidential weight and the Ellsberg paradox

“…Since Ellsberg, the objective of most of this still growing literature, usually labelled 'Knightian uncertainty', was thus to modelling decision-making which allows for such a distinction. 4 Although Ellsberg did not mention Keynes in his article, various scholars, both economists in the Keynesian tradition as well as decision theorists, have suggested a possible theoretical link with Keynes's ideas (Camerer & Weber, 1992;Carabelli, 2002;Curley & Yates, 1989;Dequech, 2000;Dolan & Jones, 2004;Einhorn & Hogarth, 1985;Fontana & Gerrard, 2004;Fox & Tversky, 1995;Runde, 1994a). The recent publication of Ellsberg's PhD dissertation (2001), submitted to the University of Harvard in 1962, actually reveals that Ellsberg was aware of Keynes's work.…”

Exploring Procedural Decision Support Systems for Wicked Problem Resolution

“…The concept, in its broadest form, has its roots in ancient Greek and Chinese epistemological and ontological inquiry (L. Buchanan & O' Connell, 2006;Peterson, 2009), where philosophers such as Aristotle and Herodotus grappled with the notions of human preferences and rationality respectively (Carabelli, 2002;Hansson, 2002;Peterson, 2009). Later, during the Renaissance and Enlightenment eras, the study of probability, utility, and risk were added to the repertoire of study by mathematicians such as Bernoulli, de Fermat, and Pascal (Bernstein, 1996;Peterson, 2009).…”