Scientifi c tools—measurement and calculation instruments, techniques of inference—straddle the line between the context of discovery and the context of justifi cation. In discovery, new scientifi c tools suggest new theoretical metaphors and concepts; and in justifi cation, these tool-derived theoretical metaphors and concepts are more likely to be accepted by the scientifi c community if the tools are already entrenched in scientifi c practice. Techniques of statistical inference and hypothesis testing entered American psychology fi rst as tools in the 1940s and 1950s and then as cognitive theories in the 1960s and 1970s. Not only did psychologists resist statistical metaphors of mind prior to the institutionalization of inference techniques in their own practice; the cognitive theories they ultimately developed about “the mind as intuitive statistician ” still bear the telltale marks of the practical laboratory context in which the tool was used.

In this paper we examine the role of social and organizational knowledge in managerial decision-making. In a series of experiments, we examined the following questions. (1) How are some implicit organizational variables such as the size of a group and the composition of a group related to risk perception and risky decisions? From a Darwinian perspective, humans have lived in small, nomadic, hunter-gatherers' groups throughout almost the entire evolutionary time. In making decisions at risk, the size of the group thus may serve as a cue signalling the structure and functions of a social group (e.g., kinship, reciprocity, interdependence among group members). To investigate the effects of these organizational variables, Wang (1996a, 1996b, 2001) used a well-known example of irrational decisions, framing effects (Tversky & Kahneman, 1981), as an empirical probe. Framing effects, characterized by an irrational reversal in risk preference due to different ways of presenting / framing the same choice outcomes, appeared only in large group contexts but disappeared in small group and kinship group contexts. Evolutionarily recurrent small group contexts (less than 1000 people) eliminated irrational reversal in risk preference. (2) Would risky choices between a sure option and a gamble of equal expected value vary as a function of the types of information provided in a decision problem? In contrast to verbal framing (e.g., presenting the same choice outcomes as if they are gains or as if they are losses), situational information about the real status of an organization should have independent reflection effects on risky choice. This so called reflection effect has been repeatedly shown in the literature, where people tend to be risk averse in gain situations but risk seeking in l...

www.mpib-berlin.mpg.de/abc Abstract: How can anyone be rational in a world where knowledge is limited, time is pressing, and deep thought is often an unattainable luxury? Traditional models of unbounded rationality and optimization in cognitive science, economics, and animal behavior have tended to view decision-makers as possessing supernatural powers of reason, limitless knowledge, and endless time. But understanding decisions in the real world requires a more psychologically plausible notion of bounded rationality. In Simple heuristics that make us smart (Gigerenzer et al. 1999), we explore fast and frugal heuristics – simple rules in the mind’s adaptive toolbox for making decisions with realistic mental resources. These heuristics can enable both living organisms and artificial systems to make smart choices quickly and with a minimum of information by exploiting the way that information is structured in particular environments. In this précis, we show how simple building blocks that control information search, stop search, and make decisions can be put together to form classes of heuristics, including: ignorance-based and one-reason decision making for choice, elimination models for categorization, and satisficing heuristics for sequential search. These simple heuristics perform comparably to more complex algorithms, particularly when generalizing to new data – that is, simplicity leads to robustness. We present evidence regarding when people use simple heuristics and describe the challenges to be addressed by this research program.

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In the 1st section empirical findings concerning shape constancy are reviewed under 10 headings: the occurrence of compromise, conditions of observation, degree of orientation, observation attitude, familiarity and representativeness, differences between forms, individual differences, background effects, effects of movement, exposure time and intensity. The 2nd section deals with several theoretical accounts of shape constancy. The shape-slant invariance hypothesis is evaluated in the light of the experimental evidence and is judged to be equivocal. A line of investigation is proposed which might reconcile the experimental data with the requirements of this hypothesis. The final section of the paper considers the methodological precautions which need to be observed in experimentation on apparent shape and apparent slant. When a form is projected by light on the retina, the differing orientations of the form with regard to the retina result in a set of different projective shapes. Under most conditions phenomenal shape is less affected by the orientation of the stimulus object with respect to the observer (0) than would be expected on the basis of the projective transformations which accompany variations in orientation. The term "shape constancy" has been introduced to designate this fact. Shape constancy is defined usually as the relative constancy of the perceived shape of an object despite variations in its orientation. This definition reflects the prevalent interest in the stability of the perceptual world. However, it is also possible to locate shape constancy within a wider range of events all characterized by a relative independence of perceived shape from retinal, projective shape. With this in mind, the phenomena relevant to