Mode-of-disparities error correction of eye-tracking data

In eye-tracking research, there is almost always a disparity between a person’s actual gaze location and the location recorded by the eye tracker. Disparities that are constant over time are systematic error. In this article, we propose an error correction method that can reliably reduce systematic error and restore fixations to their true locations. We show that the method is reliable when the visual objects in the experiment are arranged in an irregular manner—for example, when they are not on a grid in which all fixations can be shifted to adjacent locations using the same directional adjustment. The method first calculates the disparities between fixations and their nearest objects. It then uses the annealed mean shift algorithm to find the mode of the disparities. The mode is demonstrated to correctly capture the magnitude and direction of the systematic error so that it can be removed. This article presents the method, an extended demonstration, and a validation of the method’s efficacy.     

The impact of baseline trend control on visual analysis of single-case data

The impact of baseline trend control on visual analyses of AB intervention graphs was examined with simulated data at various values of baseline trend, autocorrelation, and effect size. Participants included 202 undergraduate students with minimal training in visual analysis and 10 graduate students and faculty with more training and experience in visual analysis. In general, results were similar across both groups of participants. Without statistical adjustments to correct for baseline trend, Type I errors greatly increased as baseline trend increased. With corrections for baseline trend, fewer Type I errors were made. As trend increased, participants made fewer Type II errors on the unadjusted graphs as compared to the graphs with baseline trend control. The greater Type II error rate on adjusted graphs could be an artifact of study design (i.e., participants did not know if baseline trend control had been applied), and the impact of MASAJ on Type II errors needs to be explored in detail prior to more widespread use of the method. Implications for future use of baseline trend control techniques by educational professionals are discussed.     

Evaluating sources of baseline data using dual-criteria and conservative dual-criteria methods: A quantitative analysis

Scheithauer et al. (2020) recently demonstrated that differences in the source of baseline data extracted from a functional analysis (FA) may not affect subsequent clinical decision-making in comparison to a standard baseline. These outcomes warrant additional quantitative examination, as correspondence of visual analysis has sometimes been reported to be unreliable. In the current study, we quantified the occurrence of false positives within a dataset of FA and baseline data using the dual-criteria (DC) and conservative dual-criteria (CDC) methods. Results of this quantitative analysis suggest that false positives were more likely when using FA data (rather than original baseline data) as the initial treatment baseline. However, both sources of baseline data may have acceptably low levels of false positives for practical use. Overall, the findings provide preliminary quantitative support for the conclusion that determinations of effective treatment may be easily obtained using different sources of baseline data.     

Perception naturalised: relocation and the sensible qualities

This paper offers a partial defence of a Sellarsian-inspired form of scientific realism. It defends the relocation strategy that Sellars adopts in his project of reconciling the manifest and scientific images. It concentrates on defending the causal analysis of perception that is essential to his treatment of sensible qualities. One fundamental metaphysical issue in perception theory concerns the nature of the perceptual relation; it is argued that a philosophical exploration of this issue is continuous with the scientific investigation of perceptual processes. Perception, it is argued, can, and should, be naturalised. A challenge for any account of perception arises from the fact that a subject’s experiences are connected with particular objects. We need to supply principled grounds for identifying which external physical object the subject stands in a perceptual relation to when they have an experience. According to the particularity objection presented in the paper, naive realism (or disjunctivism) does not constitute an independently viable theory since, taken on its own, it is unable to answer the objection. In appealing to a ‘direct experiential relation’, it posits a relation that cannot be identified independently of the underlying causal facts. A proper understanding of one central function of perception, as guiding extended patterns of actions, supports a causal analysis of perception. It allows us to draw up a set of necessary and sufficient conditions for perceiving that avoids well-known counterexamples. An analysis of this kind is congruent with the scientific account, according to which experiences are interpreted as inner states: sensible qualities, such as colours, are in the mind (but not as objects of perception). A Sellarsian version of the relocation story is thus vindicated.

     

A sensible formulation of the significance test

The conventional procedure for null hypothesis significance testing has long been the target of appropriate criticism. A more reasonable alternative is proposed, one that not only avoids the unrealistic postulation of a null hypothesis but also, for a given parametric difference and a given error probability, is more likely to report the detection of that difference.     

Convergence properties of an iterative procedure of ipsatizing and standardizing a data matrix,with applications to parafac/candecomp preprocessing

Centering a matrix row-wise and rescaling it column-wise to a unit sum of squares requires an iterative procedure. It is shown that this procedure converges to a stable solution. This solution need not be centered row-wise if the limiting point of the interations is a matrix of rank one. The results of the present paper bear directly on several types of preprocessing methods in Parafac/Candecomp.     

A comparison of sources of baseline data for treatments of problem behavior following a functional analysis

It is common practice in research on the treatment of problem behavior to compare levels of targeted behaviors during treatment to levels when treatment is not in place. Some researchers use data collected as part of a multielement functional analysis as the initial baseline, whereas others collect new baseline data following completion of the functional analysis. We evaluated whether the source of baseline data influences the reliability and efficiency of decision-making. Results suggest that similar decisions are made in regard to treatment efficacy using the different sources of baseline data, but using data from a multielement functional analysis as baseline may save time. Interrater agreement was adequate, but lower for some graphs than has been observed in past studies. Several potential explanations for this discrepancy are discussed.     

Anger-associated panic attacks in Cambodian refugees with PTSD; a multiple baseline examination of clinical data

Despite the increasing recognition of the importance of anger as a key aspect of post-traumatic stress disorder (PTSD), the presence of anger-induced panic attacks has been understudied in traumatized groups. The present investigation determines the prevalence of anger-associated panic attacks among Cambodian refugees suffering from PTSD. Specific characteristics of these episodes that were examined included frequency, symptoms, and cognitions (in particular, fear of death from bodily dysfunction). In a survey of 100 Khmer patients suffering PTSD, 58% reported anger-associated panic attacks in the last month. These attacks occurred at a mean rate of 6.2 attacks a month and were characterized by extreme arousal and in 81% of these cases, fears of death due to bodily dysfunction during the anger-induced panic. Mechanisms for this high rate of fear of death during anger arousal are discussed with a focus on culture-specific catastrophic cognitions.     

Estimation of trade‐off between costs of preprocessing and primary processing

When people engage in a task, they often take preliminary actions (preprocessing) to simplify primary processing. Usually, a trade‐off is made between the costs of preprocessing and primary processing. We conducted three experiments to find out whether people could adaptively estimate the utility of preprocessing depending on the task situation. The result demonstrated that in performing a high‐complexity task, almost all the participants reduced their overall task performance cost by conducting cost‐adaptive preprocessing. However, for a low‐complexity task, participants tended to conduct preprocessing even though this increased overall task performance cost. Based on these results, we discuss human nature from the viewpoint of the influence of cognitive effort.     

Attributional change and the importance of baseline recording

This single case study illustrates how attention to baseline measures prevented premature conclusions regarding the impact of a conditioning procedure upon aggressive, acting-out behavior. Five disruptive behaviors were initially delineated so that frequency distributions could be obtained. During the course of this 15-day observational period, a significant reduction in the number of these aggressive responses was noted. The proposed conditioning procedure was therefore never required. Explanations as well as implications regarding the observed alteration in behavior were discussed.     

Relations between baseline contingencies and equivalence probe performances

Following the emergence of two three-member equivalence classes (A1B1C1 and A2B2C2), 5 college students were exposed to one or more changes in the reinforcement contingencies controlling baseline conditional discriminations. AC relations were either reversed (i.e., C2 was reinforced and C1 punished when A1 was the sample; C1 was reinforced and C2 punished when A2 was the sample) or arranged randomly (i.e., C2 and C1 were reinforced and punished equally often in the presence of A1 and A2). In a third condition, the original AB and AC relations were reversed. Results showed that although baseline conditional discrimination performances were under the control of reinforcement contingencies, and performances on symmetry trials varied with baseline responding for 3 of 4 subjects when contingencies were reversed, performances on transitivity probes remained consistent with the initial equivalence class. These inconsistencies between probe and baseline performances were striking because conditional discriminations are thought to be the determinants of equivalence class performance. Similarly, the contrast between performances on symmetry and transitivity probes was of theoretical interest because equivalence classes are defined by congruent patterns of responding on probe trials.     

The influence of parafoveal preprocessing and linguistic context on the optimal landing position effect

Several experiments have shown the existence of an optimal landing position effect during isolated word recognition as well as during text reading; both the probability of refixating the test word and the gaze duration are smaller if the eye first fixates near the center of the word than if the eye first fixates other positions in the word. However, recent data indicate that the optimal landing position effect is weakened under normal reading conditions, when words are included in texts. The purpose of the present experiment was to test whether parafoveal preprocessing or linguistic context specific to the text reading situation could be responsible for this weakening. With a paradigm that approximates normal reading, albeit in a somewhat slower manner, it was shown that although the possibility of preprocessing words in parafoveal vision and of predicting them from preceding context globally affected refixation probability and gaze duration on the word, this did not strongly affect the optimal landing position effect. Since the global effects of these factors were comparable to those found by other authors in normal reading, it was concluded that the weakening of the optimal landing position effect during text reading results from the influence of other factors peculiar to this situation. Hypotheses are proposed as explanations of the effects of the manipulated factors on oculomotor behavior.     

The relationship between baseline pupil size and intelligence

Pupil dilations of the eye are known to correspond to central cognitive processes. However, the relationship between pupil size and individual differences in cognitive ability is not as well studied. A peculiar finding that has cropped up in this research is that those high on cognitive ability have a larger pupil size, even during a passive baseline condition. Yet these findings were incidental and lacked a clear explanation. Therefore, in the present series of studies we systematically investigated whether pupil size during a passive baseline is associated with individual differences in working memory capacity and fluid intelligence. Across three studies we consistently found that baseline pupil size is, in fact, related to cognitive ability. We showed that this relationship could not be explained by differences in mental effort, and that the effect of working memory capacity and fluid intelligence on pupil size persisted even after 23 sessions and taking into account the effect of novelty or familiarity with the environment. We also accounted for potential confounding variables such as; age, ethnicity, and drug substances. Lastly, we found that it is fluid intelligence, more so than working memory capacity, which is related to baseline pupil size. In order to provide an explanation and suggestions for future research, we also consider our findings in the context of the underlying neural mechanisms involved.     

Targeting those in need: baseline data from the first English National Health Service (NHS) health trainer service

As part of a wider strategy to reduce health inequalities, England's National Health Service has introduced health trainers (HTs) to facilitate healthier behaviour among disadvantaged groups. This study reports baseline data from the first English HT service: assessing whether the HTs reached socially disadvantaged clients engaging in unhealthy behaviours and describing client belief characteristics relevant to the delivery of the service. Data from 864 clients show that the service reached disadvantaged groups and that those groups were engaging in risky health behaviours. Self-efficacy about changing behaviour was not strong and clients were unlikely to have made explicit behaviour-change plans prior to attending the service. Implications for HT services around targeting those most in need and supporting psychological triggers for change are discussed.