Purpose - Sponsorship identification accuracy is typically assessed as the percentage of consumers answering "yes" when asked if a brand is a sponsor (hits). However, this fails to consider misattribution (a...
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Purpose - Sponsorship identification accuracy is typically assessed as the percentage of consumers answering "yes" when asked if a brand is a sponsor (hits). However, this fails to consider misattribution (answering "yes" for a non-sponsor brand;false alarms). Misattribution reflects consumer confusion and dilutes the benefits of an official sponsorship, offers an advantage to a non-sponsoring rival and reduces a brand's return on sponsorship investment. Informed by signal-detectiontheory (SDT), we show how hits may be disentangled from false alarms using a measure of sensitivity called d-prime (d'). A related measure of response bias (c) is also discussed. Design/methodology/approach - In Study 1, we report the results of an experiment. In Study 2, we rely on field study involving actual sponsors and fans. Findings - The use of d' and c is superior to tallying "yes" responses because they account for accurate sponsor attribution and misattribution to non-sponsor competitors. Originality/value - In the context of sponsorship, we demonstrate how d' and c can be easily calculated using Excel. Our research also includes an experimental study that establishes the hypothesized effects and then replicate results in a field setting.
Adding distracters to a display impairs performance on visual tasks (i.e. the set-size effect). While keeping the display characteristics constant, we investigated this effect in three tasks: 2 target identification, ...
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Adding distracters to a display impairs performance on visual tasks (i.e. the set-size effect). While keeping the display characteristics constant, we investigated this effect in three tasks: 2 target identification, yes-no detection with 2 targets, and 8-alternative localization. A signal detection theory (SDT) model, tailored for each task, accounts for the set-size effects observed in identification and localization tasks, and slightly under-predicts the set-size effect in a detection task. Given that sensitivity varies as a function of spatial frequency (SF), we measured performance in each of these three tasks in neutral and peripheral precue conditions for each of six spatial frequencies (0.5-12 cpd). For all spatial frequencies tested, performance on the three tasks decreased as set size increased in the neutral precue condition, and the peripheral precue reduced the effect. Larger setsize effects were observed at low SFs in the identification and localization tasks. This effect can be described using the SDT model, but was not predicted by it. For each of these tasks we also established the extent to which covert attention modulates performance across a range of set sizes. A peripheral precue substantially diminished the set-size effect and improved performance, even at set size 1. These results provide support for distracter exclusion, and suggest that signal enhancement may also be a mechanism by which covert attention can impose its effect.
Objective: To examine the utility of equal-variance signal detection theory (EVSDT) for evaluating and understanding human detection of phishing and spear-phishing e-mail scams. Background: Although the majority of cy...
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Objective: To examine the utility of equal-variance signal detection theory (EVSDT) for evaluating and understanding human detection of phishing and spear-phishing e-mail scams. Background: Although the majority of cybersecurity breaches are due to erroneous responses to deceptive phishing e-mails, it is unclear how best to quantify performance in this context. In particular, it is unclear whether equal variances can safely be assumed in the SDT model, or, relatedly, whether degree of targeting, or threat level, primarily affects mean separation or evidence variability. Method: Through an online inbox simulation, the present research found that differences in susceptibility to phishing and spear-phishing e-mails could be carefully quantified with respect to detection accuracy and response bias through the use of an EVSDT framework. Results: The results indicated that EVSDT-based point metrics are effective for modeling and measuring phishing susceptibility in the inbox task, without the need for parameter estimation or model comparison involving unequal-variance SDT (UVSDT). Threat level modulated mean separation, with no effects on signal variances. Conclusion: These findings support the viability of using EVSDT to initially assess and subsequently monitor training effectiveness for phishing susceptibility, thereby providing measures that are superior to more intuitive metrics, which typically confound an individual's bias and accuracy. Effects of threat level mapped clearly onto distribution means with no effect on variances, suggesting phishing susceptibility primarily reflects temporally stable discriminative characteristics of observers. Notably, results indicated that people are particularly poor at identifying spear-phishing e-mail threats (demonstrating only 40% accuracy).
The juxtaposition of established signal detection theory models of perception and more recent claims about the encoding of uncertainty in perception is a rich source of confusion Are the latter simply a rehash of the ...
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The juxtaposition of established signal detection theory models of perception and more recent claims about the encoding of uncertainty in perception is a rich source of confusion Are the latter simply a rehash of the former? Here we make an attempt to distinguish precisely between optimal and probabilistic computation In optimal computation the observer minimizes the expected cost under a posterior probability distribution In probabilistic computation the observer uses higher moments of the likelihood function of the stimulus on a trial-by trial basis Computation can be optimal without being probabilistic and vice versa Most signal detection theory models describe optimal computation Behavioral data only provide evidence for a neural representation of uncertainty if they are best described by a model of probabilistic computation We argue that single-neuron activity sometimes suffices for optimal computation but never for probabilistic computation A population code is needed instead Not every population code is equally suitable because nuisance parameters have to be marginalized out This problem is solved by Poisson-like but not by Gaussian variability Finally we build a dictionary between signal detection theory quantities and Poisson like population quantities (C) 2010 Elsevier Ltd All rights reserved
Neural implementation of classical High-Threshold theory reveals fundamental flaws in its applicability to realistic neural systems and to the two-alternative forced-choice (2AFC) paradigm. For 2AFC, signaldetection ...
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Neural implementation of classical High-Threshold theory reveals fundamental flaws in its applicability to realistic neural systems and to the two-alternative forced-choice (2AFC) paradigm. For 2AFC, signal detection theory provides a basis for accurate analysis of the observer's attentional strategy and effective degree of probability summation over attended neural channels. The resulting theory provides substantially different predictions from those of previous approximation analyses. Tn additive noise, attentional probability summation depends on the attentional model assumed. (I) For an ideal attentional strategy in additive noise, summation proceeds at a diminishing rate from an initial level of fourth-root summation for the first few channels. The maximum improvement asymptotes to about a factor of 4 by a million channels. (2) For a fixed attention field in additive noise, detection is highly inefficient at first and approximates fourth-root summation through the summation range. (3) In physiologically plausible root-multiplicative noise, on the other hand, attentional probability summation mimics a linear improvement in sensitivity up to about ten channels, approaching a factor of 1000 by a million channels. (4) Some noise sources, such as noise from eye movements, are fully multiplicative and would prevent threshold determination within their range of effectiveness. Such results may require reappraisal of previous interpretations of detection behavior in the 2AFC paradigm. (C) 2000 Elsevier Science Ltd. All rights reserved.
An accurate reflux-symptom relationship analysis method is an unmet need in gastroesophageal reflux disease (GERD) diagnosis. The aim of this study was to adapt signal detection theory (SDT) approach to reflux-symptom...
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An accurate reflux-symptom relationship analysis method is an unmet need in gastroesophageal reflux disease (GERD) diagnosis. The aim of this study was to adapt signal detection theory (SDT) approach to reflux-symptom relationship analysis to develop a new diagnosis method. Patients with predominant symptoms of heartburn and regurgitation were enrolled. Proton pump inhibitor (PPI)-responsive and PPI-unresponsive groups were created via interview and PPI trial. Patients then underwent stationary esophageal manometry and 24-hour multichannel intraluminal impedance-pH monitoring. SDT measurement parameters (discriminability: d and criterion: c) were calculated using empirically selected time windows (0.5, 1, 2, 3, 4 and 5 minutes). The time window that provided the highest d value was selected as the optimal time window. A cut-off d value that optimally separates two groups was found using receiver operating characteristics analysis. Sixty-three patients completed the study (45 PPI responsive). Optimal time window and cut-off d value were found as 1 and 0.767 minute, respectively. Symptom association probability (SAP) index values showed good correlation (r(S) = 0.7182, P < 0.0001) with d values. SDT approach to reflux-symptom relationship analysis showed sensitivity (89% vs. 78%) and negative predictive values (75% vs. 60%) favorable over SAP index analysis. SDT approach using 1-minute time window and 0.767 cut-off d value provides us a new and more accurate measure of reflux-symptom relationship than SAP index analysis.
Prediction accuracy of academic achievement for admission purposes requires adequate sensitivity and specificity of admission tools, yet the available information on the validity and predictive power of admission tool...
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Prediction accuracy of academic achievement for admission purposes requires adequate sensitivity and specificity of admission tools, yet the available information on the validity and predictive power of admission tools is largely based on studies using correlational and regression statistics. The goal of this study was to explore signal detection theory as a tool to extend the available information;signal detection theory allows for comparisons of selection outcomes on both group and individual levels and the development of tailor-made criteria for specific programmes and admission goals. We investigated who would or would not have been admitted applying specific criteria for each of three common admission tools, how many admitted students would fail and how many applicants who would have been successful would be rejected. Both comparisons at an individual level and the receiver operating characteristic curves at a group level revealed that scores obtained in a programme-specific matching programme and non-cognitive factors appear more valuable than regression statistics suggest when it comes to admitting applicants who will become successful students. signal detection theory allows not only for admission-goal-specific and programme-specific fine-tuning of the content of admission tools, it also informs about the effects of criteria and thus allows the setting of criteria.
Block [Block, N. (2005). Two neural correlates of consciousness. Trends in Cognitive Science, 9, 46-52] and Snodgrass (2006) claim that a signal detection theory (SDT) analysis of qualitative difference paradigms, in ...
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Block [Block, N. (2005). Two neural correlates of consciousness. Trends in Cognitive Science, 9, 46-52] and Snodgrass (2006) claim that a signal detection theory (SDT) analysis of qualitative difference paradigms, in particular the exclusion failure paradigm, reveals cases of phenomenal consciousness without access consciousness. This claim is unwarranted on several grounds. First, partial cognitive access rather than a total lack of cognitive access can account for exclusion failure results. Second, Snodgrass's Objective Threshold/Strategic (OT/S) model of perception relies on a problematic 'enable' approach to perception that denies the possibility of intentional control of unconscious perception and any effect of following different task instructions on the presence/absence of phenomenal consciousness. Many of Block's purported examples of phenomenal consciousness without cognitive access also rely on this problematic approach. Third, qualitative difference paradigms may index only a subset of access consciousness. Thus, qualitative difference paradigms like exclusion failure cannot be used to isolate phenomenal consciousness, any attempt to do so still faces serious methodological problems. (C) 2008 Elsevier Inc. All rights reserved.
This paper provides a case study of signal detection theory (SDT) as applied to a continuous monitoring dual-task environment. Specifically, SDT was used to evaluate the independent contributions of sensitivity and bi...
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This paper provides a case study of signal detection theory (SDT) as applied to a continuous monitoring dual-task environment. Specifically, SDT was used to evaluate the independent contributions of sensitivity and bias to different qualitative gauges used in process control. To assess detection performance in monitoring the gauges, we developed a Time Window-based Human-In-The-Loop (TWHITL) simulation bed. Through this test bed, we were able to generate a display similar to those monitored by console operators in oil and gas refinery plants. By using SDT and TWHITL, we evaluated the sensitivity, operator bias, and response time of flow, level, pressure, and temperature gauge-shapes developed by Abnormal Situation Management (R) (ASM (R)) Consortium (***). Our findings suggest that display density influences the effectiveness of participants in detecting abnormal shapes. Furthermore, results suggest that some shapes elicit better detection performance than others. (C) 2013 Elsevier Ltd and The Ergonomics Society. All rights reserved.
Basic results for conditional means and variances, as well as distributional results, are used to clarify the similarities and differences between various extensions of signal detection theory (SDT). It is shown that ...
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Basic results for conditional means and variances, as well as distributional results, are used to clarify the similarities and differences between various extensions of signal detection theory (SDT). It is shown that a previously presented motivation for the unequal variance SDT model (varying strength) actually leads to a related, yet distinct, model. The distinction has implications for other extensions of SDT, such as models with criteria that vary over trials. It is shown that a mixture extension of SOT is also consistent with unequal variances, but provides a different interpretation of the results;mixture SDT also offers a way to unify results found across several types of studies. (C) 2010 Elsevier Inc. All rights reserved.
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