Search

Objective: This secondary analysis of longitudinal data on Latino immigrant parents applied latent change modeling to investigate the association between within‐family change in parent–child conflict and within‐individual change in parent's psychological distress, and how within‐individual change in parenting stress mediates that association over time. Background: Immigrant parents face additional challenges when parenting their children. There is limited research regarding how parent–child conflict may influence parenting stress and parents' overall well‐being, in particular in Latino immigrant families. Method: Secondary analysis was conducted on data from a sample of 344 Latino immigrant parents who participated in a community‐based parenting skills invention. In the original intervention study, they were assigned randomly to intervention or waitlist control groups and assessed at three points: baseline, 4 months (post‐intervention), and a follow‐up 10 months after the baseline assessment. Results: Across 4 months, change in parent–child conflict was significantly associated with changes in parenting stress and psychological distress, whereas across 10 months, change in parent–child conflict was only associated with change in psychological distress. The indirect effects through parenting stress were non‐significant. However, participating in the intervention had a protective indirect effect by reducing parenting stress across 4 months and reducing psychological distress across 10 months via change in parent–child conflict. Conclusion: Changes in parent–child relations were related to changes in parents' individual well‐being, with those associations varying across different time periods. [ABSTRACT FROM AUTHOR]

Semi‐arid to temperate south‐east Australian catchments with agricultural landscapes demonstrate unique hydro‐climatic characteristics. Understanding the behaviour of soil moisture over such catchments and the influence of driving factors are crucial for hydrologic, climatic and agricultural applications. However, this is challenging due the complex, non‐linear relationship between these factors and soil moisture, and the lack of long‐term catchment scale data records. To address this, spatial and temporal patterns of soil moisture over two south‐east Australian river catchments (i.e., Krui and Merriwa) and the influence of soil texture, topography, vegetation and rainfall on soil moisture variability were evaluated using a decadal in‐situ dataset. This unique in‐situ soil moisture monitoring network is established over a semi‐arid to temperate catchment representing typical south‐east Australian agricultural landscape and the data record has captured some major climatic events. Time stability of catchment‐scale soil moisture and the potential of predicting catchment mean soil moisture content using one representative station were also examined using a linear regression model. Soil texture was found as the dominating factor driving the spatial variability of soil moisture in the area. The temporal patterns of soil moisture showed a positive agreement with vegetation dynamics and rainfall at topsoil layers (0–5 cm and 0–30 cm). A higher spatial variability of soil moisture was observed during dry catchment conditions compared to wet catchment conditions. The deeper soil layers (30–60 cm and 60–90 cm) showed highly stable soil moisture values, which might be the driving force of the agriculture in the area. A linear regression based prediction model demonstrated a good potential in estimating spatial mean soil moisture content from one representative station. The results are useful in parameterization of soil moisture variability in land surface, climatic and hydrologic models, agricultural applications and in remote sensing of soil moisture. [ABSTRACT FROM AUTHOR]

Place value concepts were measured longitudinally from kindergarten (2017) to first grade (2018) in a diverse sample (n = 279; Mage = 5.76 years, SD = 0.55; 135 females; 41% Black, 38% White, 8% Asian, 12% Latino). Children completed three syntactic tasks that required an explicit understanding of base‐10 symbols and three approximate tasks that could be completed without this explicit understanding. Approximate performance was significantly better in both age groups. A factor analysis confirmed that syntactic and approximate tasks tapped separate latent variables in kindergarten, but not in first grade. Path analyses indicated that only kindergarten approximate performance predicted overall first‐grade place value understanding. These findings suggest that explicit understanding of base‐10 principles develops from implicit, partial knowledge of multidigit numbers. [ABSTRACT FROM AUTHOR]

One of the most vexing challenges facing developmental researchers today is the statistical modeling of two or more behaviors as they unfold jointly over time. Although quantitative methodologists have studied these issues for more than half a century, no widely agreed‐upon principled strategy exists to empirically analyze codevelopmental processes. Indeed, the plethora of available options makes selecting a specific analytic approach both confusing and overwhelming. In this article, we argue that a key step in adjudicating among alternative modeling strategies is to embrace the concept of within‐ and between‐person components of change over time. First, we define the disaggregation of effects in grouped data, and then we extend these concepts to repeated measures. Then we review several available modeling strategies that capture these effects to varying degrees and raise three issues that can help to guide practice. [ABSTRACT FROM AUTHOR]

Having one's funding cut in the course of conducting a longitudinal study has become an increasingly real challenge faced by developmental researchers. The main purpose of the current work is to propose "post hoc" planned missing (PHPM) data designs as a promising solution in such difficult situations. This study discusses general guidelines that can be followed to search for viable PHPM designs within a given budget restriction. Illustrative examples across different longitudinal research contexts are provided, each showing how PHPM data designs can help salvage longitudinal studies when an unexpected funding cut occurs mid‐study. With the illustrative examples, the article also shows how developmental researchers can conveniently identify viable designs using the R package simPM. [ABSTRACT FROM AUTHOR]

The simple view of reading describes reading as the product of decoding (D) and listening comprehension (LC). However, the simple view of reading has been challenged, and evidence has proved it to be too simple to explain the complexities of reading comprehension in the elementary school years. Hypotheses have been advanced that there are cognitive‐linguistic factors that underlie the common variance between D and LC, which are malleable, although there is no clarity at this point regarding what these are. We propose that one such group of malleable cognitive factors is executive function (EF) skills. Further, we posit that EF skills play equally strong roles in explaining reading comprehension variance in emergent bilinguals and English monolinguals. We used multigroup structural equation modeling to determine the contribution of these constructs (D, LC, and EF) to reading comprehension in 425 emergent bilinguals and 302 English monolinguals in grades 2–4. The shared variance between D and LC was explained by direct and indirect effects in the models tested, with strong indirect effects for the EFs of cognitive flexibility and working memory through D and LC, respectively, for both language groups. The indirect effect of cognitive flexibility through LC on reading comprehension was considerably larger for emergent bilinguals than for English monolinguals. Considerations for a more nuanced view of the simple view of reading and its implications for practice are discussed. [ABSTRACT FROM AUTHOR]

This study has hypothesized that for many rivers the trade‐off between flow accumulation and the decrease in slope along channel length means that stream power increases downstream and, moreover, that given the low slope angles in headwater and low‐order streams, they would have insufficient stream power to erode let alone transport sediment. The study considered the stream power profile, the particle travel distances and the application of the Hjulström curve based on the velocity profile of nine, large UK catchments. The study showed that: Some rivers never showed a maximum in their longitudinal stream power profile, implying that some rivers never develop a deposition zone before they discharge at the tidal limit.Particle travel distances during a bankfull discharge event showed that for some rivers 91% of the upper main channel would not be cleared of sediment. Furthermore, while some rivers could transport a 2 mm particle their entire length in one bankfull event, for another river it would take 89 such events.The Hjulström curve shows that for three of the study rivers the upper 20 km of the river was not capable of eroding a 2 μm particle.The study has shown that for all rivers studied, erosion is focused downstream and deposition upstream. Many UK rivers have a dead zone where, on time scales of the order of centuries, no erosion or transport occurs and erosion only occurs in the lower courses of the channel where discharge rather than slope dominates – we propose these as underpowered rivers. © 2020 The Authors. Earth Surface Processes and Landforms published by John Wiley & Sons Ltd [ABSTRACT FROM AUTHOR]

Fear and positive emotionality were considered in a growth modeling context. Mothers, primarily Caucasian (91.9%) and of middle socioeconomic status, participated in play interactions with infants at 4 months (N = 148). Infant fear and positive affectivity were evaluated at 6, 8, 10, and 12 months of age. A linear trajectory was superior in explaining growth for parent report and observation-based indicators of positive affectivity and parent report of fearfulness; a piecewise model explained the nonlinear growth of observation-based fear. Responsiveness in mother-infant interactions emerged as a significant predictor of the fear trajectory, with higher sensitivity predicting lower levels of observed fear. Reciprocity, tempo, emotional tone, and intensity of mother-infant interactions also made significant contributions to temperament development; however, analyses addressing these were exploratory. [ABSTRACT FROM AUTHOR]

Particulate organic matter (POM) transiting through rivers could be lost to overbank storage, stored in-channel, added to by erosion or autochthonous production, or turned over to release greenhouse gases to the atmosphere (either while in the water column or while stored in the channel). In the UK, a net loss of POM across catchments has been recorded, and the aim here was to investigate the balances of processes acting on the POM. This study considered records of suspended sediment and POM flux in comparison to stream flow, velocity, stream power, and residence time for the River Trent (English Midlands, 8,231 km2). We show that for the lower two thirds (106 km) of the River Trent, 2% is lost to overbank storage; 10% is lost to the atmosphere in the water column; and 31% is turned over while in temporary storage. Permanent in-channel storage is negligible, and for the lower course of the river, material stored in-channel will have a residence time of the order of hundreds of days between the last flood hydrograph of one winter and the first winter storm of the next winter (usually in the same calendar year). When considered at the scale of the UK, 1% POM in transit would be lost to overbank sedimentation; 5% turned over in the water column, and 14% turned over while in temporary storage. In the upper third of the study river channel, there is insufficient stream power to transport sediment and so in-channel storage or in-channel turnover over to the atmosphere dominate. The in-channel processes of the River Trent do not conform to that expected for river channels as the headwaters are not eroding or transporting sediment. Therefore, the source of sediment must be lower down the channel network. [ABSTRACT FROM AUTHOR]

This report investigates the prediction of labor force status using observed variables, such as gender, age, and immigrant status, and more importantly, measured skill variables, including literacy proficiency and a categorical rating of educational attainment based on the 1994 International Adult Literacy Survey ( IALS), the 2003 Adult Literacy and Life Skills Survey ( ALL), and the 2011 Programme for the International Assessment of Adult Competencies ( PIAAC) projects. We explored the regression relations in the past two decades for six trend countries and subnational regions that provide data for all assessments: the United States, Norway, the Netherlands, Italy, Canada's English-speaking region, and Canada's French-speaking region. Probit regression models with latent predictors were used in this cross-sectional study to investigate how those variables are structurally related to labor market outcomes. Results show the importance of literacy proficiency and education in determining individuals' labor force status across countries/regions, but with key differences among these countries/regions. [ABSTRACT FROM AUTHOR]

Although classical statistical techniques have been a valuable tool in second language (L2) research, L2 research questions have started to grow beyond those techniques' capabilities, and indeed are often limited by them. Questions about how complex constructs relate to each other or to constituent subskills, about longitudinal development in those constructs and factors affecting that development, and about differences among populations in average amounts of complex constructs or in their relations require a broader analytical framework. Fortunately, that of structural equation modeling (SEM), a versatile and ever-expanding family of techniques, is able to accommodate such questions and many more. The current article describes some of the questions that can be addressed by SEM, presents some research examples within the existing L2 literature, and then provides examples of the incredible potential of SEM, cautions in its practice, and resources for further information. [ABSTRACT FROM AUTHOR]

An adaptation of the Family Stress Model was examined using structural equation modeling with data from 193 custodial grandmother-grandfather dyads. The model's measurement and structural components were largely invariant by grandparent gender. For grandmothers and grandfathers alike, the effects of their psychological and marital distress on grandchildren's adjustment difficulties were mediated by dysfunctional parenting. The effects of family-related contextual forces on grandchildren's adjustment were also indirect through direct effects on grandparents' psychological and marital distress. [ABSTRACT FROM AUTHOR]

The article presents a paper which evaluates landscape theory as numerical models of drainage basin evolution, as well as the present knowledge gaps and future computing challenges. It stresses that landscape evolution models have a significant role in sharpening people's thinking, which guides them toward the right observable and map out the logical consequences of transport laws. It also provides insights into the mechanisms that control catchment function and form.

Abstract: Background: Analytic models of Alzheimer’s disease (AD) tend to focus on one type of symptom and assume implicitly that no measurement error is present. These tendencies render changes in symptom domains difficult to model mathematically, although latent variable methods can accommodate both multiple symptom domains and error. This study formulated and compared underlying (latent) factor structures representing previously reported dependence and independence of symptoms of cognitive decline, functional impairment, and behavioral disturbance in AD. Methods: In confirmatory factor analyses of data from 2 cohorts of AD patients, 2 levels of latent variables were conceptualized. One general neurologic factor represented disease, and symptom factors represented cognition, function, and behavior. Two “null” models had either a single factor or 3 symptom factors. Two 2-level models treated the general factor as underlying both the observed variables and the symptom factors or treated the symptom factors as explaining variability in the observed variables after taking the general factor into account (“residualized”). Results/Conclusions: The residualized model fit the data in both cohorts significantly better than the other models, and relations in this model between some observed and latent variables were different across cohorts. Neither cohort supported a single factor model; both cohorts independently supported a residualized model that may permit differentiation of symptom- from disease-modifying effects of treatment. [Copyright &y& Elsevier]

A method for examining change in maximal reliability for pre-specified sets of congeneric measures when developing a multi-component instrument is outlined. The approach is applicable for purposes of estimation and testing of gain or loss in the maximal reliability coefficient as a consequence of adding or dropping one or more measures from a homogeneous composite with uncorrelated errors, as well as when one is concerned with optimal component choice for highest increase or correspondingly smallest drop in maximal reliability. The method is compared with a procedure for ascertaining change in unweighted sum score reliability, and implications for instrument construction and revision are discussed. The approach is illustrated with a numerical example. [ABSTRACT FROM AUTHOR]

Asymmetric patterns of frontal brain electrical activity reflect approach and avoidance tendencies, with stability of relative right activation associated with withdrawal emotions/motivation and left hemisphere activation linked with approach and positive affect. However, considerable shifts in approach/avoidance‐related lateralization have been reported for children not targeted because of extreme temperament. In this study, dynamic effects of frontal electroencephalogram (EEG) power within and across hemispheres were examined throughout early childhood. Specifically, EEG indicators at 5, 10, 24, 36, 48, and 72 months‐of‐age (n = 410) were analyzed via a hybrid of difference score and panel design models, with baseline measures and subsequent time‐to‐time differences modeled as potentially influencing all subsequent amounts of time‐to‐time change (i.e., predictively saturated). Infant sex was considered as a moderator of dynamic developmental effects, with temperament attributes measured at 5 months examined as predictors of EEG hemisphere development. Overall, change in left and right frontal EEG power predicted declining subsequent change in the same hemisphere, with effects on the opposing neurobehavioral system enhancing later growth. Infant sex moderated the pattern of within and across‐hemisphere effects, wherein for girls more prominent left hemisphere influences on the right hemisphere EEG changes were noted and right hemisphere effects were more salient for boys. Largely similar patterns of temperament prediction were observed for the left and the right EEG power changes, with limited sex differences in links between temperament and growth parameters. Results were interpreted in the context of comparable analyses using parietal power values, which provided evidence for unique frontal effects. [ABSTRACT FROM AUTHOR]

Abstract: In this ITEMS module, we frame the topic of scale reliability within a confirmatory factor analysis and structural equation modeling (SEM) context and address some of the limitations of Cronbach's α. This modeling approach has two major advantages: (1) it allows researchers to make explicit the relation between their items and the latent variables representing the constructs those items intend to measure, and (2) it facilitates a more principled and formal practice of scale reliability evaluation. Specifically, we begin the module by discussing key conceptual and statistical foundations of the classical test theory model and then framing it within an SEM context; we do so first with a single item and then expand this approach to a multi‐item scale. This allows us to set the stage for presenting different measurement structures that might underlie a scale and, more importantly, for assessing and comparing those structures formally within the SEM context. We then make explicit the connection between measurement model parameters and different measures of reliability, emphasizing the challenges and benefits of key measures while ultimately endorsing the flexible McDonald's ω over Cronbach's α. We then demonstrate how to estimate key measures in both a commercial software program (Mplus) and three packages within an open‐source environment (R). In closing, we make recommendations for practitioners about best practices in reliability estimation based on the ideas presented in the module. [ABSTRACT FROM AUTHOR]