A stochastic model of consideration set sizes

This paper proposes a new model of consideration set sizes, which relies on a stochastic modelling approach to better understand data patterns. The paper combines the Poisson distribution with the lognormal distribution proposed by Hauser and Wernerfelt (1990) to create the Poisson lognormal (PLN) model of consideration set sizes. An advantage of PLN is that it allows variance within a given individual consumer. This is a crucial factor for brand managers who wish to choose a particular market to promote their brand, as a higher within‐individual variance suggests that there is more chance for a consumer to change their consideration set size, whereas a lower within‐individual variance indicates that a consumer tends to stick to his/her consideration set size. The paper then uses 10 datasets including service, durable and fast‐moving consumer goods across four countries to validate the new model and compare it with the lognormal model. The results show that PLN gives a good fit to these data. It outperforms the lognormal model. The average mean absolute percentage error of the PLN model is 12 per cent, whereas that of the lognormal model is 26 per cent. For managerial implications, the paper proposes a better tool to help brand managers analyse the nature and intensity of competition that is facing their brands. Also, relying on its stochastic element, the proposed model can help brand managers predict future brand consideration by their consumers, as well as evaluate any change in brand consideration, caused by marketing activity such as sales promotion and advertising. Copyright © 2014 John Wiley & Sons, Ltd.     

The coupling between spatial attention and other components of task-set: A task-switching investigation

Is spatial attention reconfigured independently of, or in tandem with, other task-set components when the task changes? We tracked the eyes of participants cued to perform one of three digit-classification tasks, each consistently associated with a distinct location. Previously we observed, on task switch trials, a substantial delay in orientation to the task-relevant location and tendency to fixate the location of the previously relevant task—“attentional inertia”. In the present experiments the cues specified (and instructions emphasized) the relevant location rather than the current task. In Experiment 1, with explicit spatial cues (arrows or spatial adverbs), the previously documented attentional handicaps all but disappeared, whilst the performance “switch cost” increased. Hence, attention can become decoupled from other aspects of task-set, but at a cost to the efficacy of task-set preparation. Experiment 2 used arbitrary single-letter cues with instructions and a training regime that encouraged participants to interpret the cue as indicating the relevant location rather than task. As in our previous experiments, and unlike in Experiment 1, we now observed clear switch-induced attentional delay and inertia, suggesting that the natural tendency is for spatial attention and task-set to be coupled and that only quasi-exogenous location cues decouple their reconfiguration.     

Carry-over of attentional settings between distinct tasks: A transient effect independent of top-down contextual biases

Top-down attentional settings can persist between two unrelated tasks, influencing visual attention and performance. This study investigated whether top-down contextual information in a second task could moderate this “attentional inertia” effect. Forty participants searched through letter strings arranged horizontally, vertically, or randomly and then made a judgement about road, nature, or fractal images. Eye movements were recorded to the picture search and findings showed greater horizontal search in the pictures following horizontal letter strings and narrower horizontal search following vertical letter strings, but only in the first 1000 ms. This shows a brief persistence of attentional settings, consistent with past findings. Crucially, attentional inertia did not vary according to image type. This indicates that top-down contextual biases within a scene have limited impact on the persistence of previously relevant, but now irrelevant, attentional settings.     

A Fuzzy Topsis Method for Prioritized Aggregation in Multi‐Criteria Decision Making Problems

Aggregation in a decision making environment requires the fusion of opinions of a group of decision makers. The group of decision makers are required to analyse a set of interrelated criteria that are usually measured on a linguistic scale. This process requires, in many instances, to capture experts experience, intuition and thinking that are traditionally expressed in a linguistic fashion rather than a numerical fashion. Furthermore, the necessity of considering the relationship between the criteria to the overall decision must be considered by the group of decision makers. This paper extends the application of fuzzy numbers, fuzzy relative importance scores (FRIS), fuzzy relative weights (FRW) and the fuzzy technique of order preference by similarity to ideal solution (TOPSIS) in prioritized aggregation. This extension provides a mean to systematically aggregate a group of decision makers' views for a set of interrelated criteria that are measured on a linguistic scale. First, an overview of the application of fuzzy numbers and the characteristics of aggregating fuzzy numbers in multi‐criteria decision making problems are presented. Then, the application of TOPSIS in fuzzy environments is presented. Next, past research is highlighted to present prioritized aggregation and the different aggregation operators' classes. Subsequently, a new prioritized aggregation method is presented. This method utilizes fuzzy TOPSIS with prioritized aggregation in fuzzy environments. Finally, the fuzzy prioritized aggregation method presented in this paper is applied on an actual case study. According to the results, the method presented in this paper provides a systematic approach to capture the uncertainty and imprecision associated with quantifying linguistic measurements in multi‐criteria decision making problems. Furthermore, it considers the relationship between the set of linguistically measured criteria undergoing prioritized aggregation in a fuzzy environment. Lastly, findings, conclusions and future work are presented. Copyright © 2016 John Wiley & Sons, Ltd.     

数字生态系统中创业机会的形成与发展：基于社会资本理论的探究

数字创业浪潮方兴未艾, 机会属性变化引起的数字创业机会形成与变化规律尚未被揭示。本研究以数字生态系统作为研究情境, 分析创业者利用数字生态系统可供性积累的社会资本, 如何影响创业机会形成与发展。从机会的合意性维度和内容维度两方面解释创业机会的变化规律, 考察创业者认知监控与新创企业数字化程度对这一路径的调节作用。本研究拓展社会资本理论在数字创业背景下的应用, 深化数字生态系统中的创业机会研究, 有助于指导创业者利用数字平台开展“破坏性创造”, 提升机会识别质量和效率, 促进创业生态系统建设。     

The influence of distracter and target features on distracter induced blindness

The inhibitory effect of the processing of target-like distracters has already been shown to affect the conscious detection of simple motion and simple orientation stimuli in a random dot kinematogram. In two experiments we examined the effects of single-feature motion distracters, single-feature orientation distracters, and combined-feature distracters containing both motion and orientation information. The target was specified as a coherent motion episode (Experiment 1) or as a combined-feature episode where the coherent motion was accompanied by an abrupt change in line orientation (Experiment 2). Results showed that (a) the respective feature-specific inhibitory processes operate separately even when the distracter features are presented simultaneously and (b) both inhibitory processes contribute to the blindness effect when the conjunction of two features is defined as the target. Again, this inhibitory-process is feature-specific: Only features that are defined in the task are represented in the inhibitory task set. In case of combined- feature task-sets, these representations remain separate, so that combined-feature distracters as well as single-feature distracters are able to induce blindness effects.     

Aging Extends the Time Required to Switch Cognitive Set

ABSTRACT

The Attentional Blink (AB) refers to a decrease in the chance of detecting a second target in a rapid sequence of items if it occurs within approximately 500 ms of a first target. In this study the efficiency of establishing and switching cognitive set for older adults (mean age 71.62 years) relative to young adults (mean age 21.33 years) was investigated. Three increasingly complex conditions of the AB paradigm were employed, each of which required participants to identify a coloured square (T1) and a letter (T2) within a stream of distracters. Accuracy of identification of T2 decreased for both young and older adults as complexity increased. In Condition 1, selection criteria for both targets were fully specified, while T1 acted as a direct cue to the selection criteria for T2 in Condition 2. Older participants took longer to establish cognitive set in this condition. Condition 3 contained an added requirement to activate a pre-determined rule for T2 selection. The basic requirement to establish cognitive set ‘online’, however, seemed to disguise any additional potential problems associated with the additional load required for Condition 3 for older adults. Younger adults were cognitively slowed in Condition 3 relative to Condition 2, suggesting that it is the need to use an internally generated cue to switch cognitive set that requires extra time for them. The significantly larger AB demonstrated by the older participants indicated an impaired ability to rapidly establish cognitive set. The findings are discussed in light of the current literature on cognitive aging, the AB and task switching.     

Multiple attentional sets while monitoring rapid serial visual presentations

The present study examined whether observers are able to establish multiple attentional sets to concurrently monitor two different spatial locations. Observers identified a target letter in red or cyan among nontarget letters of other heterogeneous colours during a temporal feature search. A peripheral distractor display consisted of one item of either the same colour as the current target, and the other potential target colour, or an irrelevant colour that could never be the target. They identified an odd-ball colour letter among homogenous colours during a singleton search. The results revealed that observers maintained multiple attentional sets for detecting two singletons or for targets involving two (or three) features. However, they were unable to maintain a mixture of sets. Moreover, exposure to a distractor containing feature that corresponded to a feature of the current target was advantageous for target identification. The presence or absence of this set-specific capture depended on top-down knowledge and did not occur automatically in the singleton-detection stream. These results demonstrate a limitation in the flexibility of attentional sets. Although two singleton detections were possible, multiple attentional templates for a more complex attentional set could not be maintained concurrently when monitoring multiple rapid serial visual presentations.     

Development and validation of an Argentine set of facial expressions of emotion

Pictures of facial expressions of emotion are used in a wide range of experiments. The last decade has seen an increase in the number of studies presenting local sets of emotion stimuli. However, only a few existing sets contain pictures of Latin Americans, despite the growing attention emotion research is receiving in this region. Here we present the development and validation of the Universidad Nacional de Cordoba, Expresiones de Emociones Faciales (UNCEEF), a Facial Action Coding System (FACS)-verified set of pictures of Argentineans expressing the six basic emotions, plus neutral expressions. FACS scores, recognition rates, Hu scores, and discrimination indices are reported. Evidence of convergent validity was obtained using the Pictures of Facial Affect in an Argentine sample. However, recognition accuracy was greater for UNCEEF. The importance of local sets of emotion pictures is discussed.