Perceptual Categorization: Connectionist Modelling and Decision Rules

Although it is currently popular to model human associative learning using connectionist networks, the mechanism by which their output activations are converted to probabilities of response has received relatively little attention. Several possible models of this decision process are considered here, including a simple ratio rule, a simple difference rule, their exponential versions, and a winner-take-all network. Two categorization experiments that attempt to dissociate these models are reported. Analogues of the experiments were presented to a single-layer, feed-forward, delta-rule network. Only the exponential ratio rule and the winner-take-all architecture, acting on the networks' output activations that corresponded to responses available on test, were capable of fully predicting the mean response results. In addition, unlike the exponential ratio rule, the winner-take-all model has the potential to predict latencies. Further studies will be required to determine whether latencies produced under more stringent conditions conform to the model's predictions.     

How a maximizing orientation affects trade-offs between desirability and feasibility: The role of outcome- versus process-focused decision making

This research examines how maximizers make decisions when they must trade-off between desirability and feasibility attributes. Across four studies, we demonstrate that maximizers tend to prefer choices offering more desirability to those offering more feasibility and respond more favorably to a product's advertising when it highlights desirability more than feasibility attributes. Furthermore, we show that maximizers' focus on outcomes rather than processes drives their preference for desirability, such that changing from an outcome to a process focus can redirect their interest from desirability to feasibility. By contrast, satisficers do not prefer products higher in desirability to those higher in feasibility and are not more receptive to ads highlighting desirability attributes. Furthermore, because satisficers may focus on both the outcome and the process, priming either one is redundant and does not alter their preference for desirability or feasibility.     

Local Opposition to the Construction of a Nuclear Power Station: Differential Salience of Impacts1

This study examined attitudes among 290 residents of three villages in South-West England toward proposals to build a nuclear power station nearby. Respondents were split into four groups according to whether they were neutral or in favor of a new power station either locally or elsewhere in the UK (Group PN), against one locally but neutral or pro elsewhere (LO), or moderately (MO) or extremely (XO) against a new power station both locally and elsewhere. The perceived impact of a nuclear power station on local life was assessed by 30 items. The PN group expected most benefit or least damage on all 30 items. On a majority of items the mean ratings of the LO group resembled those of the XO's more than did those of the MO's. A stepwise discriminant analysis yielded two interpretable functions. The first reflected a trend over the groups in the order PN-LO-MO-XO and was marked particularly by concern with impact on personal peace of mind. The second fuction discriminated the LO's from the other groups, suggesting that they were relatively less concerned with specifically nuclear risks, but more concerned with environmental conservation.     

Disarmament Decisions as Social Dilemmas1

The individual deciding on a nuclear weapons production policy is faced with a dilemma in which a choice must be made to support one of several conflicting defense policies. In order to investigate the social-psychological variables that are related to armament policy decision making, a telephone survey was conducted in the City of St. Louis, Missouri. Adult subjects (N= 110) responded to questions concerned with cognitive, attitudinal, and emotional responses to nuclear arms. Participants were also asked to choose a weapons production policy for the United States under conditions of continued and decreased Soviet nuclear arms production. Results indicated that respondents decisions about nuclear weapons production were related to their support for deterrence, the availability of their nuclear-related images, their emotional response to nuclear war, their attributions of responsibility for the prevention of nuclear war, and their political party affiliation. Distinctions between antinuclear decision-makers and pronuclear decision-makers are discussed.     

Children's perception of certain musical properties: scale and contour

Children's perception of scale and contour in melodies was investigated in five studies. Experimental tasks included judging transposed renditions of melodies (Studies 1 and 3), discriminating between transposed renditions of a melody (Study 2), judging contour-preserving transformations of melodies (Study 4), and judging similarity to a familiar target melody of transformations preserving rhythm or rhythm and contour (Study 5). The first and second studies showed that young children detect key transposition changes even in familiar melodies and they perceive similarity over key transpositions even in unfamiliar melodies. Young children also are sensitive to melodic contour over transformations that preserve it (Study 5), yet they distinguish spontaneously between melodies with the same contour and different intervals (Study 4). The key distance effect reported in the literature did not occur in the tasks of this investigation (Studies 1 and 3), and it may be apparent only for melodies shorter or more impoverished than those used here.