Epistemic trust: modeling children's reasoning about others' knowledge and intent

A core assumption of many theories of development is that children can learn indirectly from other people. However, indirect experience (or testimony) is not constrained to provide veridical information. As a result, if children are to capitalize on this source of knowledge, they must be able to infer who is trustworthy and who is not. How might a learner make such inferences while at the same time learning about the world? What biases, if any, might children bring to this problem? We address these questions with a computational model of epistemic trust in which learners reason about the helpfulness and knowledgeability of an informant. We show that the model captures the competencies shown by young children in four areas: (1) using informants’ accuracy to infer how much to trust them; (2) using informants’ recent accuracy to overcome effects of familiarity; (3) inferring trust based on consensus among informants; and (4) using information about mal‐intent to decide not to trust. The model also explains developmental changes in performance between 3 and 4 years of age as a result of changing default assumptions about the helpfulness of other people.     

Domestic dogs’ (Canis familiaris) choices in reference to agreement among human informants on location of food

When interacting with others, informants may offer conflicting information or information of varying accuracy. Recent research suggests that young children do not trust all informants equally and are selective in both whom they solicit for information and whose claims they support. We explored whether domestic dogs (Canis familiaris) are similarly sensitive to agreement among informants. To this end, we utilized a common human gesture, pointing, to which recent research suggests dogs are sensitive. We conducted two experiments in which an experimenter secretly hid food in one of two clear containers while the dog was distracted. Next, a small group moved to indicate the food's location using stationary points positioned above the containers. In Experiment 1, two experimenters moved to stand behind the non-baited container, while a third experimenter moved to stand behind the baited container. Then, all directed one static point at the container in front of them. Experiment 2 exactly resembled Experiment 1 with the exception that the single experimenter standing behind the baited container directed two static points at the container (one with each hand). Dogs chose the container indicated by the majority in Experiment 1 significantly more often than chance, but chose the container indicated by the minority in Experiment 2 significantly more often than chance. This suggests that the number of points, not the number of people, more strongly influenced dogs' choices.     

Biased attentional processing of positive stimuli in social anxiety disorder: an eye movement study

Despite the established relationship between social anxiety and attentional bias towards threat, a growing base of evidence suggests that social anxiety is additionally maintained by a deficit in the attentional processing of positive information. However, it remains unclear which component of attention is implicated in this deficit. Using eye movement-based measures and a novel attentional cuing methodology, the present study sought to investigate the presence of anxiety-linked bias in attentional engagement with, attentional disengagement from, and total fixation time to, socially relevant emotional stimuli in individuals diagnosed with social anxiety disorder, relative to non-socially anxious controls. Socially anxious individuals were found to exhibit faster attentional disengagement from positive stimuli, and reduced total fixation time to all emotional stimuli, relative to controls. Additionally for socially anxious individuals, lower total fixation times to positive stimuli were associated with higher levels of state anxiety. No differential pattern of engagement was evident between groups. We conclude that social anxiety is maintained in part by the aberrant processing of positive social stimuli.     

Effects of parafoveal word length and orthographic features on initial fixation landing positions in reading

Previous research has demonstrated that readers use word length and word boundary information in targeting saccades into upcoming words while reading. Previous studies have also revealed that the initial landing positions for fixations on words are affected by parafoveal processing. In the present study, we examined the effects of word length and orthographic legality on targeting saccades into parafoveal words. Long (8?C9 letters) and short (4?C5 letters) target words, which were matched on lexical frequency and initial letter trigram, were paired and embedded into identical sentence frames. The gaze-contingent boundary paradigm (Rayner, 1975) was used to manipulate the parafoveal information available to the reader before direct fixation on the target word. The parafoveal preview was either identical to the target word or was a visually similar nonword. The nonword previews contained orthographically legal or orthographically illegal initial letters. The results showed that orthographic preprocessing of the word to the right of fixation affected eye movement targeting, regardless of word length. Additionally, the lexical status of an upcoming saccade target in the parafovea generally did not influence preprocessing.     

Putting their best foot forward: emotional disclosure on facebook

Abstract Facebook has become a widely used online self-representation and communication platform. In this research, we focus on emotional disclosure on Facebook. We conducted two studies, and results from both self-report and observer rating show that individuals are more likely to express positive relative to negative emotions and present better emotional well-being on Facebook than in real life. Our study is the first to demonstrate impression management on Facebook through emotional disclosure. We discuss important theoretical and practical implications of our study.     

Teachers' Understandings of Probability

Probability is an important idea with a remarkably wide range of applications. However, psychological and instructional studies conducted in the last two decades have consistently documented poor understanding of probability among different populations across different settings. The purpose of this study is to develop a theoretical framework for describing teachers' understandings of probability. To this end, we conducted an 8-day seminar with eight high school statistics teachers in the summer of 2001. The data we collected include videotaped sessions and interviews, teachers' written work, and researchers' field notes. Our analysis of the data revealed that there was a complex mix of conceptions and understandings of probability, both within and across the teachers, which were situationally triggered, often incoherent when the teachers tried to reflect on them, and which did not support their attempts to develop coherent pedagogical strategies regarding probability and statistical inference.     

Convergent,Discriminant, and Incremental Validity of the Pictorial Attitude Implicit Association Test and the Picture Story Exercise as Measures of the Implicit Power Motive

The Pictorial Attitude Implicit Association Test (PA‐IAT) has recently been proposed as new measure of implicit motives. We report a study that provides the first evidence for the convergent validity of the PA‐IAT by showing that the PA‐IAT correlates significantly with a standard measure of implicit motives [i.e. the Picture Story Exercise (PSE)]. Discriminant validity of the PA‐IAT was verified in the sense that the PA‐IAT shared virtually no common variance with explicit motive measures. Our analyses revealed that the PA‐IAT and PSE can best be conceived as related but distinct measures. We further showed that the PA‐IAT had incremental validity in predicting performance on a memory recall task over and above the PSE. In general, our results confirm that the PA‐IAT is a valid measure of implicit motives and can serve as valid alternative to the PSE. Copyright © 2012 John Wiley & Sons, Ltd.     

Characteristics and Correlates of Cigarette Use Among Recent U.S. Veterans

Little is known about the smoking habits and cessation efforts of veterans returning from Iraq and Afghanistan, many of whom will seek health care services in the public sector. This project documents rates of smoking and quit attempts among veterans receiving Veteran's Health Administration (VHA) health care and describes the relationship between current smoking use/cessation and demographic characteristics, quality of life, and potential alcohol misuse.

A large representative sample of Iraq/Afghanistan era veterans was surveyed using the VA Survey of Healthcare Experiences of Patients (Wright, Craig, Campbell, Schafer, &; Humble, 2006 Wright, S. M., Craig, T., Campbell, S., Schaefer, J. and Humble, C. 2006. Patient satisfaction of female and male users of Veterans Health Administration services. Journal of General Internal Medicine, 21(Suppl. 3): S26–S32. [Crossref], [PubMed] , [Google Scholar]). One third of respondents reported smoking during the past year and 24% reported currently smoking. Current smoking status was more prevalent among those who reported less education and lower household income. Current smoking status was also related to lower mental and physical health quality of life and higher potential alcohol misuse scores. Quit attempts were significantly less common among reserve component veterans and quitters reported higher incomes and were slightly older. The frequency of cigarette smoking among recent veterans underscores the importance of addressing smoking cessation efforts within this population. Individual characteristics associated with current smoking, cessation efforts, and relapse may help tailor cessation treatment for this growing cohort of new veterans.