Mapping Among Number Words,Numerals, and Nonsymbolic Quantities in Preschoolers

In mathematically literate societies, numerical information is represented in 3 distinct codes: a verbal code (i.e., number words); a digital, symbolic code (e.g., Arabic numerals); and an analogical code (i.e., quantities; Dehaene, 1992). To communicate effectively using these numerical codes, our understanding of number must involve an understanding of each representation as well as how they map to other representations. In the current study, we looked at 3- and 4-year-old children’s understanding of Arabic numerals in relation to both quantities and number words. The results suggest that the mapping between quantities and numerals is more difficult than the mapping between numerals and number words and between number words and quantities. Thus, we compared 2 competing models designed to investigate how children represent the meanings of Arabic numbers—whether numerals are mapped directly to the quantities they represent or instead if numerals are mapped to quantities indirectly via a direct mapping to number words. We found support for the latter suggesting that children may first map numerals to number words (another symbolic representation) and only through this mapping are numerals subsequently tied to the quantities they represent. In addition, unlike both mappings involving quantity, the mapping between the 2 symbolic representations of number (numerals and number words) was not set-size-dependent, therefore providing further evidence that children may map symbols to other symbols in the absence of a quantity referent. Together, the results provide new insight into the important processes involved in how children acquire an understanding of symbolic representations of number.     

Genetic and environmental influences on early literacy skills across school grade contexts

Recent research suggests that the etiology of reading achievement can differ across environmental contexts. In the US, schools are commonly assigned grades (e.g. ‘A’, ‘B’) often interpreted to indicate school quality. This study explored differences in the etiology of early literacy skills for students based on these school grades. Participants included twins drawn from the Florida Twin Project on Reading (n = 1313 pairs) aged 4 to 10 years during the 2006–07 school year. Early literacy skills were assessed with DIBELS subtests: Oral Reading Fluency (ORF), Nonsense Word Fluency (NWF), Initial Sound Fluency (ISF), Letter Naming Fluency (LNF), and Phoneme Segmentation Fluency (PSF). School grade data were retrieved from the Florida Department of Education. Multi‐group analyses were conducted separately for subsamples defined by ‘A’ or ‘non‐A’ schools, controlling for school‐level socioeconomic status. Results indicated significant etiological differences on pre‐reading skills (ISF, LNF, and PSF), but not word‐level reading skills (ORF and NWF). There was a consistent trend of greater environmental influences on pre‐reading skills in non‐A schools, arguably representing ‘poorer’ environmental contexts than the A schools. Importantly, this is the case outside of resources linked with school‐level SES, indicating that something about the direct environment on pre‐reading skills in the non‐A school context is more variable than for A schools.     

Changes with Age in Subjective Well-Being Through the Adolescent Years: Differences by Gender

A one-year follow up study was conducted on a sample of 940 Spanish adolescents aged mostly from 10 to 15 in order to explore the extent to which their subjective well-being (SWB) changes from one year to the next, and whether these changes are the same for both genders regardless of the instrument used to measure SWB. Participants responded to the same four SWB scales twice, with an interval of a year in between. A decrease in the levels of SWB is identified from the years 11–12 onwards, the decrease in girls being more marked. Multiple-item, domain-based scales (Brief Multidimensional Student’s Life Satisfaction Scale and Personal Well-Being Index) are more sensitive than single-item scales (Overall Life Satisfaction and Happiness Taking into Account Overall Life) in detecting this decrease. Implications for the study of SWB are discussed from a developmental perspective.     

The relation between overcommitment and burnout: does it depend on employee job satisfaction?

Using the Conservation of Resources (COR) theory as a framework, we hypothesized a maladaptive role played by overcommitment in the escalation of burnout. We further specified our model by testing an interaction effect of job satisfaction. By using a longitudinal design, we proposed a moderated mediational model in which burnout at Time 1 (T1) increases overcommitment, which in turn leads to more burnout one month later. We further expected to find a moderating role of job satisfaction in the link between overcommitment and burnout at Time 2 (T2). A group of 86 white-collar workers in personnel services in Italy (longitudinal response rate = 77.48%) participated in our study. The findings supported our hypotheses even when controlling for gender and role stressors. In particular, by using bootstrapping procedures to test mediation, we found evidence that employees reporting burnout tend to develop a maladaptive coping style, i.e., overcommitment, which in turn increases burnout over time. This relation was particularly strong for dissatisfied employees. These results highlight the importance of overcommitment for burnout escalation, as well as of job satisfaction, since it may mitigate, at least in the short term, the effect of such dysfunctional strategies.     

Simple Structure Detection Through Bayesian Exploratory Multidimensional IRT Models

In modern validity theory, a major concern is the construct validity of a test, which is commonly assessed through confirmatory or exploratory factor analysis. In the framework of Bayesian exploratory Multidimensional Item Response Theory (MIRT) models, we discuss two methods aimed at investigating the underlying structure of a test, in order to verify if the latent model adheres to a chosen simple factorial structure. This purpose is achieved without imposing hard constraints on the discrimination parameter matrix to address the rotational indeterminacy. The first approach prescribes a 2-step procedure. The parameter estimates are obtained through an unconstrained MCMC sampler. The simple structure is, then, inspected with a post-processing step based on the Consensus Simple Target Rotation technique. In the second approach, both rotational invariance and simple structure retrieval are addressed within the MCMC sampling scheme, by introducing a sparsity-inducing prior on the discrimination parameters. Through simulation as well as real-world studies, we demonstrate that the proposed methods are able to correctly infer the underlying sparse structure and to retrieve interpretable solutions.