Switching attention within and between categories: Evidence for intracategory inhibition

In a variation of the Posner and Snyder (1975b) paradigm, subjects made speeded “same” or “different” responses to pairs of digits or letters on the basis of name identity (Experiment 1) or physical identity (Experiment 2). Each target pair was preceded by an informative (letter or digit) or noninformative (plus-sign) warning signal. The letter or digit represented by an informative warning signal had a high probability of appearing in the subsequent target pair (expected condition). On trials in which the expected stimulus did not appear in the target pair, the target pair belonged with equal probability to either the same category (either letters or digits) as the expected stimulus or to the opposite category (unexpected-similar and unexpected-opposite conditions, respectively). The pattern of “benefits” and “costs” of attentional expectancy found by Posner and Snyder for “same” responses was replicated: Subjects were faster and more accurate in the expected condition than in the neutral (uninformative warning signal) condition, but slower and less accurate in the unexpected conditions. Present theoretical interest concerns “same” response times and accuracy for the two unexpected conditions. Under instructions emphasizing accuracy as well as speed (Experiments 1 and 2), performance was worse in the unexpected-similar condition than in the unexpected-opposite condition. Only when instructions deemphasized accuracy (Experiment 2) was performance better in the unexpected-similar condition than in the unexpected-opposite condition. The fact that subjects may have more difficulty switching attention within a category than between categories (at least when instructions emphasize accuracy as well as speed) contrasts sharply with current theoretical emphasis on intracategorical facilitation effects in the priming paradigm. The results are interpreted within the framework of a model of attention (Keele & Neill, 1978) in which the activation of associates to the focus of attention is actively and optionally suppressed so as to reduce present or potential interference with the focal information processing.     

Is an equal interval scale an equal discriminability scale?

Stevens and Galanter’s (1957) iterative procedure for minimizing bias in category scaling was used for the scaling of loudness of white noise. The spacing obtained deviated systematically from a spacing constructed in accordance with an equal discriminability scale from a previous experiment (Eisler & Montgomery, 1972). For the stimulus spacing yielding a “pure” category scale, a magnitude scale was constructed too. Since the category scale could be predicted accurately by Fechnerian integration of this magnitude scale, it was concluded that the “pure” category scale is a pure discrimination scale. The discrepancy between the equal discriminability scale and the “pure” category scale was interpreted as a bias in the former scale due to greater recognizability of stimuli located at the extremes of the stimulus range.     

A Categorical Approach to Probability Theory

First, we discuss basic probability notions from the viewpoint of category theory. Our approach is based on the following four “sine quibus non” conditions: 1. (elementary) category theory is efficient (and suffices); 2. random variables, observables, probability measures, and states are morphisms; 3. classical probability theory and fuzzy probability theory in the sense of S. Gudder and S. Bugajski are special cases of a more general model; 4. a good model allows natural modifications. Second, we show that the category ID of D-posets of fuzzy sets and sequentially continuous D-homomorphisms allows to characterize the passage from classical to fuzzy events as the minimal generalization having nontrivial quantum character: a degenerated state can be transported to a nondegenerated one. Third, we describe a general model of probability theory based on the category ID so that the classical and fuzzy probability theories become special cases and the model allows natural modifications. Finally, we present a modification in which the closed unit interval [0,1] as the domain of traditional states is replaced by a suitable simplex.     

The Effect of Evidential Impact on Perceptual Probabilistic Judgments

In a series of three behavioral experiments, we found a systematic distortion of probability judgments concerning elementary visual stimuli. Participants were briefly shown a set of figures that had two features (e.g., a geometric shape and a color) with two possible values each (e.g., triangle or circle and black or white). A figure was then drawn, and participants were informed about the value of one of its features (e.g., that the figure was a “circle”) and had to predict the value of the other feature (e.g., whether the figure was “black” or “white”). We repeated this procedure for various sets of figures and, by varying the statistical association between features in the sets, we manipulated the probability of a feature given the evidence of another (e.g., the posterior probability of hypothesis “black” given the evidence “circle”) as well as the support provided by a feature to another (e.g., the impact, or confirmation, of evidence “circle” on the hypothesis “black”). Results indicated that participants’ judgments were deeply affected by impact, although they only should have depended on the probability distributions over the features, and that the dissociation between evidential impact and posterior probability increased the number of errors. The implications of these findings for lower and higher level cognitive models are discussed.     

An experimental analysis of psychometric functions in a threshold discrimination task with four response categories1

An experiment on a threshold discrimination task with four response categories was conducted to check the implicit assumptions of a threshold discrimination task with three response categories. Consideration of a task with three response categories, for example, “stronger,”“don't know,” and “weaker,” leads us to anticipate a relation between position parameters and that between the sizes of scale parameters of a model for a task with four response categories, such as, “stronger,”“probably stronger,”“probably weaker,” and “weaker.” That is, position parameters will be equidistant between adjacent categories and the middle scale parameter will be the largest. The results of the experiment on a four‐category task did not support these anticipated relation, and a possibility of biases in the estimation of point of subjective equality (PSE), using a three‐category task is pointed out. As an alternative to a three‐category task, a four‐category task is suggested when more than two categories are required.     

Effects of generic language on category content and structure

We hypothesized that generic noun phrases (“Bears climb trees”) would provide important input to children’s developing concepts. In three experiments, four-year-olds and adults learned a series of facts about a novel animal category, in one of three wording conditions: generic (e.g., “Zarpies hate ice cream”), specific–label (e.g., “This zarpie hates ice cream”), or no-label (e.g., “This hates ice cream”). Participants completed a battery of tasks assessing the extent to which they linked the category to the properties expressed, and the extent to which they treated the category as constituting an essentialized kind. As predicted, for adults, generics training resulted in tighter category–property links and more category essentialism than both the specific-label and no-label training. Children also showed effects of generic wording, though the effects were weaker and required more extensive input. We discuss the implications for language-thought relations, and for the acquisition of essentialized categories.     

Ouch! – a logotherapeutic discourse of butch and tattooed in China

• This is a study of a small group of self‐identified butch lesbians in their consumption of tattoos. The emotion‐laden experience of negotiating social symbolism and self‐identity (Elliott, 1997 ) in the context of hyperrealism (Baudrillard, 1983 ) has given rise to what Frankl ( 1984 ) has described as “existential vacuums.” Frankl suggested that these “existential vacuums” can be filled with a higher level of meaning. An artifact of consumption, the tattoo, is used by the informants in this study as a component of bricolage in the DIY process of constructing a new self (Elliott, 1997 ), with the entire process of being tattooed – particularly the hyper‐stimulation and pain of the procedure – further “existentializing” a new existence of “imagined masculinity.” This new existence that transcends suffering and assigns new meaning to life is the principle idea of Frankl's logotherapy (Frankl, 1984 ; Barnes, 2000 ; Blair, 2004 ).

Copyright © 2010 John Wiley & Sons, Ltd.     

The Challenge of Being a Challenger: Social Dominance Orientation Shapes the Impact of “Challenger vs. Leader” Comparisons

The current research investigates when and how comparative advertising effectiveness is shaped by social dominance orientation (SDO), that is, the degree to which one desires to maintain the status quo in social hierarchies. We examine these issues with regard to “challenger vs. leader” comparisons that seek to change the relative standing of competitors in a product category by documenting the superiority of challenger brands over market leaders. Findings demonstrate that the resistance to change characterizing high (vs. low) SDO individuals makes them respond (1) less favorably to “challenger vs. leader” comparisons that seek to alter the existing category hierarchy and (2) more favorably to “leader vs. challenger” comparisons that preserve this status quo in the category hierarchy. The theoretical implications of these findings are discussed, as are avenues for future research.     

What Are the “True” Statistics of the Environment?

A widespread assumption in the contemporary discussion of probabilistic models of cognition, often attributed to the Bayesian program, is that inference is optimal when the observer's priors match the true priors in the world—the actual “statistics of the environment.” But in fact the idea of a “true” prior plays no role in traditional Bayesian philosophy, which regards probability as a quantification of belief, not an objective characteristic of the world. In this paper I discuss the significance of the traditional Bayesian epistemic view of probability and its mismatch with the more objectivist assumptions about probability that are widely held in contemporary cognitive science. I then introduce a novel mathematical framework, the observer lattice, that aims to clarify this issue while avoiding philosophically tendentious assumptions. The mathematical argument shows that even if we assume that “ground truth” probabilities actually do exist, there is no objective way to tell what they are. Different observers, conditioning on different information, will inevitably have different probability estimates, and there is no general procedure to determine which one is right. The argument sheds light on the use of probabilistic models in cognitive science, and in particular on what exactly it means for the mind to be “tuned” to its environment.     

Evidence against “absolute” scaling

Zwislocki and Goodman (1980) argue that there exists an “absolute coupling” of numbers to sensation magnitudes and conclude that, when subjects are left unconstrained by a designated stimulus-number pair, they may use this “absolute” scale. The purpose of the studies reported here was to test whether Zwislocki and Goodman’s (1980) absolute scaling procedure reduces contextual effects due to variations in the stimulus spacing. It was found that magnitude estimations vary as a function of the stimulus spacing, regardless of whether subjects are instructed to use a standard and modulus, and, furthermore, that category ratings yield effects of the stimulus spacing comparable to those obtained with magnitude estimations. It is argued that removing the so-called constraints of a standard and modulus does not yield an “absolute” scale of sensation. The absolute scaling procedure increases response variability and thereby lowers the power of a test for contextual effects.     

ASSESSING STIMULUS CONTROL IN NATURAL SETTINGS: AN ANALYSIS OF STIMULI THAT ACQUIRE CONTROL DURING TRAINING

When a learner is taught a new response, the stimuli that influence its display are often unknown. The presence or absence of these stimuli alters the probability of occurrence of the response. By identifying the stimuli influencing the probability of newly acquired responses, interventionists may program for their generalization more effectively and efficiently. This investigation describes the application of an operant methodology to assess functional relationships between responses and specific stimulus variables. Four young adults with moderate mental retardation were taught to include “please” as part of requests they made in school. Four environmental stimuli, present during training, were assessed for the controlling properties they acquired. Each of the four was assessed prior to and after training by presenting it in isolation (i.e., the other three were varied). If the presence of a single stimulus associated with training did not occasion “please,” then pairs of stimuli were probed. The results revealed that single-stimulus probing occasioned responding by only 1 learner; paired-stimulus probing set the occasion for including “please” by 2 others. Control of the 4th learner's responding was lost before training was introduced, because he began including “please” in his requests during baseline. The implications of these results are discussed in terms of analyzing stimulus control and promoting stimulus generalization.     

Categorical target templates: Typical category members are found and identified quickly during word-cued search

What information do people use to guide search when they lack precise details about the appearance of their target? In this study, we employed categorical (word-cued) search and eye tracking, to examine how category typicality influences search performance. We found that typical category members were fixated and identified more quickly than atypical categories. This finding held when the participant was cued at the superordinate level (finding “clothing” among non-clothing items) or the basic level (finding a “shirt” among other clothing items). This suggests that categorical target templates may be constructed by piecing together features from the most typical category member(s).     

样例多样性和流畅性信念对类别学习判断的影响

目的:通过三个实验考查样例特征、流畅性和信念对类别学习及其元认知判断的影响。方法:实验1采用2(样例特征)×2(测试类型)的组内设计以检验样例特征的作用; 实验2采用2(样例特征)×2(测试类型)×2(流畅性)的组内设计以检验流畅性的作用; 实验3采用2(样例特征)×2(测试类型)×2(流畅性信念)的混合设计以检验信念对类别学习判断的作用。结果表明:样例特征影响学习成绩、类别学习判断和流畅感; 流畅性不会影响类别学习判断; 原理解释能够有效建立“关于流畅性的信念”,且“关于流畅性的信念”对类别学习判断起作用。即样例多样性和流畅性信念对类别学习判断起作用,支持信念假说。     

The paradox of the universal triangle: Concepts,language, and prototypes

For over 300 years, the humble triangle has served as the paradigmatic example of the problem of abstraction. How can we have the idea of a general triangle even though every experience with triangles is with specific ones? Classical cognitive science seemed to provide an answer in symbolic representation. With its easily enumerated necessary and sufficient conditions, the triangle would appear to be an ideal candidate for being represented in a symbolic form. I show that it is not. Across a variety of tasks—drawing, speeded recognition, unspeeded visual judgments, and inference—representations of triangles appear to be graded and context dependent. I show that using the category name “triangle” activates a more prototypical representation than using an arguably coextensive cue, “three-sided polygon”. For example, when asked to draw “triangles” people draw more typical triangles than when asked to draw “three-sided polygons”. Altogether, the results support the view that (even formal) concepts have a graded and flexible structure, which takes on a more prototypical and stable form when activated by category labels.     

Metacognition in psychophysical judgment: An unfolding view of comparative judgments of mental workload

An experiment is reported in which it was found that when subjects were required to indicate which of two visual extents was more difficult to categorize as “long” or “short,” they executed these categorizations and then measured the distance of the representation of each stimulus from the long-short category boundary; the stimulus nearer the boundary was judged to be the more difficult. When they were requested to indicate which was easier to categorize, they selected the alternative that was farther. Coombs’s theory of data (1952, 1964) and his unfolding theory of preferential choice (1950, 1964) provided the conceptualization of metacognition in this psychophysical task context. Strong support for the probabilisitic version of unfolding theory was obtained from the observed selective effects of laterality on the levels of stochastic transitivity attained for various classes of triples and the reliably longer times for comparisons with bilateral pairs than with unilateral pairs. The semantic congruity effects obtained, together with the changes in the form of the relationship between probability and response time as a function of practice, can be best accounted for by an evidence accrual theory in which the distances from the active reference point are measured and compared with a criterion on each evidence accrual. No support is provided for the view that propositionally based semantic “ease”- “difficulty” codes serve as the basis for these metacognitive comparative judgments of ease and difficulty.     

More about linda or conjunctions in context

Abstract

Tversky and Kahneman (1982; 1983) reported that subjects rated the con junction of two events as more likely than one of the component events. This “conjunction effect” is an error in terms of formal probability, where the probability of more happening is always smaller than the probability of less. They explained this effect in terms of a “representativeness” heuristic. This paper focuses on the context of the problem and the suggestions implied by the questions in the task. The three studies reported here provide evidence that context effects and implicit suggestions alter subjects' judgements. Tvenky and Kahneman's models take no account of such factors. Two studies show that when implicit suggestions are reduced, subjects are much less prone to the conjunction “effect”. Subjects take being asked the question “Is person X a Y?”, as providing evidence that X may be Y.