Spatial and conjoint models based on pairwise comparisons of dissimilarities and combined effects: Complete and incomplete designs

In pairwise multidimensional scaling, a spatial representation for a set of objects is determined from comparisons of the dissimilarity of any two objects drawn from the set to the dissimilarity of other pairs of objects drawn from that set. In pairwise conjoint scaling, comparisons among the joint effects produced by pairs of objects, where the objects in a pair are drawn from separate sets, are used to determine numerical representations for the objects in each set. Monte Carlo simulations of both pairwise dissimilarities and pairwise conjoint effects show that Johnson's algorithm can provide good metric recovery in the presence of high levels of error even when only a small percentage of the complete set of pairwise comparisons are tested.     

Cultivating expertise in informal reasoning.

People generally develop some degree of competence in general informal reasoning and argument skills, but how do they go beyond this to attain higher expertise? Ericsson has proposed that high-level expertise in a variety of domains is cultivated through a specific type of practice, referred to as "deliberate practice." Applying this framework yields the empirical hypothesis that high-level expertise in informal reasoning is the outcome of extensive, deliberate practice. This paper reports results from two studies evaluating the hypothesis. University student participants completed 12 weeks of deliberate practice in informal reasoning. Quantity of practice was recorded by computer, and additionally assessed via self-report. The hypothesis was supported: Students in both studies showed a large improvement, and practice, as measured by computer, was related to amount of improvement in informal reasoning. These findings support adopting a deliberate practice approach when attempting to teach or learn expertise in informal reasoning.     

Aims and Exclusivity

If belief has an aim by being a (quasi) intentional activity, then it ought to be the case that the aim of belief can be weighed against other aims one might have. However, this is not so with the putative truth aim of belief: from the first‐person perspective, one can only be motivated by truth considerations in deliberation over what to believe (exclusivity). From this perspective then, the aim cannot be weighed. This problem is captured by David Owens's Exclusivity Objection to belief having an aim (2003). Conor McHugh (2012; 2013) has responded to this problem by denying the phenomenon of exclusivity and replacing it with something weaker: demandingness. If deliberation over what to believe is characterised by demandingness and not exclusivity, this allows for the requisite weighing of the truth aim. I argue against such a move by suggesting that where non‐evidential considerations play a role in affecting what we believe, these considerations merely change the standards required for believing in a particular context, they do not provide non‐evidential reasons for forming or withholding belief, which are considered as such from the deliberative perspective. Exclusivity thus remains, and so too does Owens's objection.     

The dimensions of tonal experience: A nonmetric multidimensional scaling approach

Subjects were required in each trial to directly compare two pairs of tones and indicate which pair of tones had the greater subjective difference or dissimilarity. Eleven tones differing in both intensity and frequency were employed. Subjects made binary comparisons among the 55 tone pairs which can be formed from the set of 11 tones. These paired comparisons of tonal intervals were used to determine a two-dimensional Euclidean representation for tonal experience. Loudness and pitch appeared as orthogonal dimensions in this representation. However, a 45-deg rotation of loudness and pitch axes produced axes which could be identified as volume and density. This relationship suggested that volume and density were simple functions of pitch and loudness. Volume and density predictions based on this two-dimensional representation were shown to provide a good account of the data from three experiments on volume and density.     

"Ratio" and "difference" judgments for length, area, and volume: are there two classes of sensory continua?

Subjects were required to judge ratios and differences of (a) line length for pairs of lines, (b) area for pairs of squares, and (c) volume for pairs of cubes. Nonmetric analyses of these judgments indicated that all subjects were able to make consistent ratio judgments for all three continua. Many of the subjects, when asked to judge subjective differences, however, performed as if they were judging subjective ratios rather than differences. The data for the few subjects who appeared to be judging subjective differences were not consistent across subjects and conditions. Previous studies of ratio and difference judgments of loudness and heaviness, on the other hand, showed the opposite pattern, in that subjects most often behaved as if they were judging sensory differences when asked to judge sensory ratios. We propose that ratio judgments are more natural to perceptual continua along which stimuli are easily "decomposed" into a number of smaller perceptual units.     

Derived Stimulus Relations Produce Mediated and Episodic Priming

The Psychological Record - If derived stimulus relations can serve as a beginning behavioral model of semantic meaning, many of the cognitive findings shown with semantic relations should apply to...     

Balancing cognitive demands: control adjustments in the stop-signal paradigm

Cognitive control enables flexible interaction with a dynamic environment. In 2 experiments, the authors investigated control adjustments in the stop-signal paradigm, a procedure that requires balancing speed (going) and caution (stopping) in a dual-task environment. Focusing on the slowing of go reaction times after stop signals, the authors tested 5 competing hypotheses for post-stop-signal adjustments: goal priority, error detection, conflict monitoring, surprise, and memory. Reaction times increased after both successful and failed inhibition, consistent with the goal priority hypothesis and inconsistent with the error detection and conflict hypotheses. Post-stop-signal slowing was greater if the go task stimulus repeated on consecutive trials, suggesting a contribution of memory. We also found evidence for slowing based on more than the immediately preceding stop signal. Post-stop-signal slowing was greater when stop signals occurred more frequently (Experiment 1), inconsistent with the surprise hypothesis, and when inhibition failed more frequently (Experiment 2). This suggests that more global manipulations encompassing many trials affect post-stop-signal adjustments.     

Post-stop-signal slowing: strategies dominate reflexes and implicit learning

Control adjustments are necessary to balance competing cognitive demands. One task that is well-suited to explore control adjustments is the stop-signal paradigm, in which subjects must balance initiation and inhibition. One common adjustment in the stop-signal paradigm is post-stop-signal slowing. Existing models of sequential adjustments in the stop-signal paradigm suggest that post-stop-signal slowing may be based solely on the events of the previous trial, suggesting that post-stop-signal slowing is a reflexive byproduct of a stop signal. Alternatively, post-stop-signal slowing could be the result of implicit learning or strategic adjustment. The authors report three experiments that manipulated the probability of stop trial repetition and found that these contingencies eliminate, reverse, or greatly increase post-stop-signal slowing. When the contingency was not instructed or cued, modest adjustments of post-stop-signal slowing occurred, suggesting implicit learning. When the contingency was cued, performance adjustments occurred on the next trial, suggesting that strategies dominated post-stop-signal slowing. These results show that post-stop-signal slowing is not a reflexive byproduct of the stop signal. The large changes in strategy accompany large changes in task factors, suggesting that the modest post-stop-signal slowing usually observed may be a result of the relatively static task environment that does not encourage large strategic changes.     

Post-stop-signal adjustments: inhibition improves subsequent inhibition

Performance in the stop-signal paradigm involves a balance between going and stopping, and one way that this balance is struck is through shifting priority away from the go task, slowing responses after a stop signal, and improving the probability of inhibition. In 6 experiments, the authors tested whether there is a corresponding shift in priority toward the stop task, speeding reaction time to the stop signal. Consistent with this hypothesis, stop-signal reaction time (SSRT) decreased on the trial immediately following a stop signal in each experiment. Experiments 2-4 used 2 very different stop signals within a modality, and stopping improved when the stop stimulus repeated and alternated. Experiments 5 and 6 presented stop signals in different modalities and showed that SSRT improved only when the stop stimulus repeated within a modality. These results demonstrate within-modality post-stop-signal speeding of response inhibition.