Base-rate effects in category learning: a comparison of parallel network and memory storage-retrieval models

Exemplar-memory and adaptive network models were compared in application to category learning data, with special attention to base rate effects on learning and transfer performance. Subjects classified symptom charts of hypothetical patients into disease categories, with informative feedback on learning trials and with the feedback either given or withheld on test trials that followed each fourth of the learning series. The network model proved notably accurate and uniformly superior to the exemplar model in accounting for the detailed course of learning; both the parallel, interactive aspect of the network model and its particular learning algorithm contribute to this superiority. During learning, subjects' performance reflected both category base rates and feature (symptom) probabilities in a nearly optimal manner, a result predicted by both models, though more accurately by the network model. However, under some test conditions, the data showed substantial base-rate neglect, in agreement with Gluck and Bower (1988b).     

Memory storage and retrieval processes in category learning

The detailed course of learning is studied for categorization tasks defined by independent or contingent probability distributions over the features of category exemplars. College-age subjects viewed sequences of bar charts that simulated symptom patterns and responded to each chart with a recognition and a categorization judgment. Fuzzy, probabilistically defined categories were learned relatively rapidly when individual features were correlated with category assignment, more slowly when only patterns carried category information. Limits of performance were suboptimal, evidently because of capacity limitations on judgmental processes as well as limitations on memory. Categorization proved systematically related to feature and exemplar probabilities, under different circumstances, and to similarity among exemplars of categories. Unique retrieval cues for exemplar patterns facilitated recognition but entered into categorization only at retention intervals within the range of short-term memory. The findings are interpreted within the framework of a general array model that yields both exemplar-similarity and feature-frequency models as special cases and provides quantitative accounts of the course of learning in each of the categorization tasks studied.     

Death by 1000 ‘true fans’: Do marketing laws apply to music listening?

The advice to musicians and marketers is to focus on what they love: a truism for practitioners is to find 1000 ‘true fans’ and make $100 from each of them (Kelly, 2008. 1000 True fans. The Technium). If this advice is correct, we should see musicians with loyal user bases engaging more with their favourite artists and less with other music, suggesting a narrow targeting strategy would suffice. On the other hand, the established marketing laws indicate that the listeners of very different genres should overlap more than conventional wisdom would suggest, supporting the need for a much broader approach to targeting potential audiences. Given these conflicting views, musicians need to know if they should market to their existing listeners, the listeners of music similar to theirs (i.e., the same genre), or if they should try to reach a much wider audience. We turn to established choice patterns from the marketing literature to address these questions in the music context. This study examines 84,000,000 observations of music listening from 27,000 unique global users between 2013 and 2014 and survey data from 2019 containing music listening from over 1000 representative respondents in the United States. The results show that listening follows the Duplication of Purchase law for genres, artists, albums, and songs, at an annual, 6-months, 3-months, 1-month, and 1-week period, with no indication of partitioned music listening. The implication is that musicians should try to reach all potential listeners, regardless of what they already listen to. These findings contribute to the theoretical knowledge about duplication analyses of various durations, extend the contexts of choice behaviour that exhibit this pattern, and managerially, to knowledge about the extent of potential audiences and ‘share of ear’ competition.     

SIGNIFICANCE TESTING IN PSYCHOLOGICAL RESEARCH:

Abstract— Empirical surveys show that reports of significance tests appear in the vast majority of articles in psychological research journals and are relied on by both investigators and journal reviewers when making decisions about replication of experiments and submission and acceptance of research reports Evaluation of claims by critics that significance testing is, nonetheless, counterproductive yields suggestions for improvements of prevailing practices, but also the recommendation that decisions about significance testing versus alternative procedures should remain the province of the individual investigator, unconstrained by mandates or prohibitions by publishers or officials of scientific associations. The prime focus for efforts toward improvement of research design and data analysis in psychology and other behavioral sciences should be upgrading the mathematical and general scientific preparation of students preparing for research careers in these fields     

Serial position functions for letter identification at brief and extended exposure durations

The properties of serial position functions for tachistoscopic report were investigated over a wide range of viewing times. Four-letter strings of random consonants were presented in varying display locations relative to the fixation point with the observers’ eye movements monitored to limit them to a single fixation for each display. Salient properties of the serial position curves include an overall central-peripheral gradient, higher performance at the ends than the interior of letter strings regardless of absolute location, and left-right asymmetry in the visual field, all of these being largely independent of viewing time. Errors reflecting loss of positional information are prominent even at extended viewing times, are more nearly symmetrical in the left and right visual fields than other types of errors, and, in contrast to item errors, occur less frequently in letter sequences that have high frequencies in English. Further, transposition errors exhibit a pronounced peripheral-to-central drift, possibly reflecting gradients of positional uncertainty. Such gradients may be implicated in the peripheral-central asymmetry of the lateral interference effects exerted by other letters on a target letter in a nonfoveal location.     

Optimizing Engagement in Behavioral Parent Training: Progress Toward a Technology-Enhanced Treatment Model

Low-income families are more likely to have a child with an early-onset Behavior Disorder (BD); yet, socioeconomic strain challenges engagement in Behavioral Parent Training (BPT). This study follows a promising pilot to further examine the potential to cost-effectively improve low-income families’ engagement in and the efficiency of BPT. Low-income families were randomized to (a) Helping the Noncompliant Child (HNC; McMahon & Forehand, 2003), a weekly, mastery-based BPT program that includes both the parent and child or (b) Technology-Enhanced HNC (TE-HNC), which includes all of the standard HNC components plus a parent mobile application and therapist web portal that provide between-session monitoring, modeling, and coaching of parent skill use with the goal of improved engagement in the context of financial strain. Relative to HNC, TE-HNC families had greater homework compliance and mid-week call participation. TE-HNC completers also required fewer weeks to achieve skill mastery and, in turn, to complete treatment than those in HNC without compromising parent satisfaction with treatment; yet, session attendance and completion were not different between groups. Future directions and clinical implications are discussed.     

I can see myself helping: The effect of self-awareness on prosocial behaviour

Many studies indicate that increasing self-awareness leads to individuals reflecting on their values and ideals (Silvia & Duval, 2001). This self-reflection appears to increase prosocial behaviour (Berkowitz, 1987). However, previously studies typically manipulated self-awareness in situations in which the individual may have felt pressure from the researcher to help. Thus, experimenter pressure to behave prosocially confounds the self-awareness explanation provided in past research. We used a novel experimental paradigm to manipulate self-awareness and remove the researcher's presence to decrease the likelihood that the participant would conform to experimenter demand. Participants were 36 college students (M_age = 19.52; 25 women). The results indicated a strong probability that the experimental condition participants were more prosocial than control condition participants. These findings provide additional support for the hypothesis that self-reflection increases prosocial behaviour, even without experimenter demands. These findings and the importance of studying objective self-awareness in light of the coronavirus are discussed.