Numerosity discrimination in preschool children

We used a numerical bisection procedure to examine preschool children's sensitivity to the numerical attributes of stimuli. In Experiment 1 children performed two tasks. In the Cups Task they earned coins for choosing a green cup after two drumbeats and a blue cup after eight drumbeats. In the Gloves Task they earned coins for raising a red glove on their left hand after two drumbeats and a yellow glove on their right hand after eight drumbeats. Then in each task a psychometric function was obtained by presenting intermediate numerosities and recording the percentage of trials in which children chose the "many" option. In Experiment 2 children's performance in a '2 vs. 8' discrimination was compared with their performance in a "4 vs. 16" discrimination. Results showed that the individual psychometric functions were of two types, one in which the percentage of "many" choices increased gradually with stimulus numerosity and another in which it increased abruptly, in a step-like manner. Although the average point of subjective equality was close to the geometric mean of the anchor numerosities and the average functions for "2 vs. 8" and "4 vs. 16" superimposed when plotted on a common scale (the scalar property), the individual data were highly variable both across tasks (Cups and Gloves) and numerosity ranges ('2 vs. 8' and '4 vs. 16'). It is suggested that between- and within-subjects variability in the psychometric function is related to children's verbalizations about the sample stimulus.     

An interactive multiobjective procedure for selecting medium-term countermeasures after nuclear accidents

This paper presents a methodology for supporting medium-term decisions in the context of nuclear accidents. An interactive procedure based on a multiobjective linear model is introduced, allowing the set of feasible strategies to be explored. This procedure enables the users to express preferences on both criterion values and the structure of the strategies. Additional flexibility is provided by the possibility of integrating evolutive constraints during the decision process. © 1998 John Wiley & Sons, Ltd.     

Reducing Perceptions of Time Required to Complete Math Assignments by Adding Problems to Assignments: A Synthesis of the Additive Interspersal Research

Results from nine experiments were analyzed to evaluate the relationship between relative problem completion rates (RPCR) and judgments of time involving mathematics assignments. For each experiment, control assignments contained only target mathematics computation or word problems. Matched experimental assignments contained similar target problems with additional, briefer problems interspersed after every third target problem. After working on each assignment for the same amount of time, students selected the assignment that they judged would require the least or most amount of time to complete. Regression analysis revealed a significant linear relationship between RPCR (i.e., PCR on experimental assignments/PCR on control assignments) and time perceptions (r=.97). As RPCR increased, the percentage of students judging the experimental assignments as being less time consuming increased proportionally. Discussion focuses on application of time perception theories to educational settings.     

Psychophysics of remembering: to bias or not to bias

Delayed matching to sample is typically a two-alternative forced-choice procedure with two sample stimuli. In this task the effects of varying the probability of reinforcers for correct choices and the resulting receiver operating characteristic are symmetrical. A version of the task where a sample is present on some trials and absent on others is analogous to a yes/no recognition task. We describe data from two experiments where an asymmetry in performance in the yes/no task could be attributed to a change in response bias with increasing retention-interval duration from a matching-law perspective, but not from a signal-detection perspective. Both approaches make explicit assumptions about response bias. The apparent inconsistency between the two approaches to the treatment of response bias is resolved in terms of a model proposed by K. G. White and J. T. Wixted (1999) which predicts asymmetrical matching-law functions and receiver operating characteristics without making any assumptions about response bias.     

Maternal sensitivity moderates the impact of prenatal anxiety disorder on infant responses to the still-face procedure

Animal studies have demonstrated the interactive effects of prenatal stress exposure and postnatal rearing style on offspring capacity to manage stress. However, little is known about how parenting quality impacts the association between maternal prenatal anxiety and stress reactivity in human infants. This prospective study examined the impact of prenatal anxiety disorder and maternal caregiving sensitivity on infants’ responses to a standardised interactive stressor (still-face procedure). Eighty-four women completed a clinical interview during pregnancy to assess anxiety symptoms meeting DSM-IV diagnostic criteria. At infant age 7 months, maternal sensitivity to infant distress and infant negative affect were observed and coded during the still-face procedure. Maternal postnatal (concurrent) anxiety and depression were also assessed at this time. Results indicated a negative association between maternal sensitivity to infant distress and infant negative affect responses to the still-face procedure. An unexpected finding was a positive association between parity and infant reactivity. The main effect for sensitivity was qualified by a significant interaction, p < .05, suggesting that the impact of sensitivity was particularly marked among infants of women who experienced an anxiety disorder during pregnancy. This finding is consistent with a cumulative risk model suggesting that maternal prenatal anxiety and quality of maternal care act in concert to shape infant outcomes.     

Reading and related skills in Grades 6, 7, 8 and 9: French normative data from EVALEC

IntroductionTo appropriately assess reading difficulties, tests designed according to an appropriate theoretical framework and based on normative data are required.ObjectiveWe used EVALEC (Sprenger-Charolles, Colé, Béchennec, & Kipffer-Piquard, 2005) to collect data on the word-level reading skills and reading-related skills (phonemic awareness, phonological short-term memory, and rapid naming) of middle school children (Grades 6 to 9, about 80 in each grade).MethodIn the tests focused on word-level reading skills, the effects of regularity (regular vs. irregular words), lexicality, and length (short vs. long irregular words and pseudowords) were examined. Accuracy and processing times were recorded for all tests.ResultsThe effects of both regularity and lexicality were significant, whatever the measure and independently of grade. Both accuracy and speed were lower for longer pseudowords, whereas length did not have a significant effect on irregular word latencies and, surprisingly, long irregular words were read more accurately than short ones. Reading level as assessed by a standardized test (Lefavrais, 2005) was not predicted by phonological short-term memory; rapid naming (color names) and phonemic awareness were both predictors but, in both cases, only response times predicted reading level.ConclusionThese results, and particularly those from the reading tasks, are discussed in relation to models of written-word recognition developed to account for the reading of multisyllabic items (Perry, Ziegler, & Zorzi, 2010) in orthographies shallower than English (Perry, Ziegler, & Zorzi, 2014).     

Self-deception and discrepancies in self-evaluation

Self-deception is an intricate psychological construct, grounded in relatively little empirical evidence as an individual difference variable. The present research offers a direct test of one of the central scales of self-deception—the Self-Deception Enhancement (SDE) scale—by comparing explicit and implicit self-evaluations. Using the Affect Misattribution Procedure (AMP), participants (N = 150) reported about their implicit self-evaluation. These ratings were compared to explicit self-reports about self-evaluation. Results showed that higher self-deception was associated with a larger discrepancy between explicit and implicit self-evaluations. Specifically, higher self-deception was associated with a more positive explicit self-evaluation but with a more negative implicit self-evaluation. These findings offer one of the first direct tests of the SDE, supporting its viability.     

Contrasting behavioral looking procedures: a case study on infant speech segmentation

This paper compared three different procedures common in infant speech perception research: a headturn preference procedure (HPP) and a central-fixation (CF) procedure with either automated eye-tracking (CF-ET) or manual coding (CF-M). In theory, such procedures all measure the same underlying speech perception and learning mechanisms and the choice between them should ideally be irrelevant in unveiling infant preference. However, the ManyBabies study (ManyBabies Consortium, 2019), a cross-laboratory collaboration on infants’ preference for child-directed speech, revealed that choice of procedure can modulate effect sizes. Here we examined whether procedure also modulates preference in paradigms that add a learning phase prior to test: a speech segmentation paradigm. Such paradigms are particularly important for studying the learning mechanisms infants can employ for language acquisition. We carried out the same familiarization-then-test experiment with the three different procedures (32 unique infants per procedure). Procedures were compared on various factors, such as overall effect, average looking time and drop-out rate. The key observations are that the HPP yielded a larger familiarity preference, but also reported larger drop-out rates. This raises questions about the generalizability of results. We argue that more collaborative research into different procedures in infant preference experiments is required in order to interpret the variation in infant preferences more accurately.