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An observational block design has I blocks matched for covariates and J individuals per block, but treatments were not randomly assigned to individuals within blocks, as would have been done in an experiment. Tightening an observational block design means selecting J ′ < J individuals from each block, and possibly I ′ ≤ I blocks, to construct a new observational block design that, in some way, addresses unmeasured biases from nonrandom treatment assignment. Tightening must preserve covariate balance while altering the design to achieve some additional objective. An optimization algorithm is introduced that achieves this while maintaining the block structure by finely balancing covariates across blocks and through optimal subset matching. An example is considered in detail, both to motivate and illustrate the tightening of an observational block design. Two tightened designs are built from a study of light daily alcohol consumption and its possible effects on HDL cholesterol. One tightened design adjusts for an outcome tentatively presuming it was unaffected by the treatment. The second tightened design uses a differential effect to remove bias from an unobserved general disposition that promotes several treatments. An R package tightenBlock implements the method, contains the data, and in that package the help-file for the function tighten reproduces the example. [ABSTRACT FROM AUTHOR]

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Objectives: This study aimed to compare the efficacy of dietary intake of eicosapentaenoic acid (EPA; 20:5 ω-3) and docosahexaenoic acid (DHA; 22:6 ω-3) on very short sleep duration (<5 h/night) in adults. Methods: The bootstrap method was used in the multinomial logistic regression to estimate the ORs and corresponding 95% confidence intervals (CIs) of very short sleep duration. We used rolling window method to analyze the effects of EPA and DHA dietary intakes on very short sleep durations in men and women over age. To illustrate the stability of the results for the selected window width, we built a shiny application. Results: Compared to the first quartile, the mean ORs of EPA intake on very short sleep duration and the corresponding 95% CIs for the second, third and fourth quartiles of EPA intake among men under 32 years old were 1.50 (0.56, 3.44) mg, 1.55 (0.59, 3.48) mg, and 3.99 (1.15, 10.01) mg, respectively. Among women over 44 years old, the ORs for DHA intake were 1.12 (0.81, 1.52) mg, 0.94 (0.68, 1.29) mg, and 0.62 (0.38, 0.98) mg for the second, third and fourth quartiles, respectively. Conclusions: The associations of EPA and DHA with very short sleep duration are sex- and age-dependent. In males under the age of 32, a significant positive correlation exists between dietary EPA intake and very short sleep duration. For women above 44 years of age, an increase in DHA intake can notably ameliorate issues of very short sleep duration. [ABSTRACT FROM AUTHOR]

Copyright of Zeitschrift für Erziehungswissenschaft is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Students' proficiency in the language of instruction is essential for their mathematical learning. Accordingly, language-responsive instruction, which includes adapting teaching material to students' language needs, is thought to promote mathematical learning, particularly for students with lower levels of proficiency in the language of instruction. However, empirical evidence for the effectiveness of this type of instruction in heterogeneous classrooms is scarce, and potential differential effects for learners with different learning prerequisites still need to be studied. The present study examines whether language-responsive instructional materials can promote students' learning of fractions. We conducted a quasi-experimental intervention study with a pre- and posttest in Grade 7 (N = 211). The students were assigned to one of three instructional conditions: fraction instruction with or without additional language support or to a control group. The results showed that both intervention groups had higher learning gains than the control group. However, students with lower proficiency in the language of instruction benefited more from fraction instruction with additional language support than without it. The opposite was true for students with higher proficiency in the language of instruction. Moreover, learning gains depended on students' levels of mathematics anxiety. Our study contributes to a more detailed understanding of the effectiveness of language-responsive instruction in heterogeneous classrooms. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed at exploring the differential effects of different corporate governance (CG) indicators on risk management practices in Islamic financial institutions (IFIs) and conventional financial institutions (CFIs) of Pakistan. It also investigated the moderating role of institutional quality (IQ) in shaping the effects of CG practices on financial institutions of Pakistan. Design/methodology/approach: A sample of 57 financial institutions including commercial banks, insurance companies and Modarba companies over the period 2006–2017 is used to carry out the empirical analysis. The authors applied the robust two-step system-generalized method of moments estimator, which is also called the dynamic panel data estimator. They also built the PCA-based composite index of CG and IQ by using different indicators to investigate the moderating role of IQ. They used three proxies for risk taking, five for CG and one for Shari'ah governance. To test the validity of the instruments, they applied the Arellano and Bond's (1991) AR (1) and AR (2) tests and the J-statistic of Hansen (1982). Findings: The results provided strong evidence that several individual characteristics of CG and the composite index are significantly related to the operational risk, the liquidity risk and the Z-score (a proxy for solvency risk). The results also revealed that IQ significantly and substantially contributes in reducing the level of risks. Finally, the estimation results indicated that the effects of CG on risk management are significantly different at IFIs and CFIs. This differential impact is mainly attributed to the fundamental differences in business models, operational strategies and contractual obligations of both types of institutions. Practical implications: The findings of this study are important for enhancing our understanding of how CG relates to risk taking in Islamic and conventional financial services industries and how good quality institutions are important for formulating the governance effects on the risk-taking behavior of financial institutions. The findings suggest that a suitable size of board should be chosen to manage the risk effectively. As the findings show that the risk-taking behavior of IFIs differs from that of CFIs, the regulators and international standard setting bodies should tailor the regulatory frameworks accordingly. Originality/value: This paper is different from the existing studies in four aspects. First, to the best of the authors' knowledge, this is the first empirical investigation in Pakistan, which does the comparison of IFIs and CFIs while examining the impacts of CG on risk management. Second, the paper constructs the composite index of CG by considering several different indicators of governance and examines the combined effect of governance indicators on risk management process. Third, this paper adds to the growing literature on the role of IQ by investigating whether it acts as a moderator between CG structures and risk management and if yes, then whether this moderating role is different for IFIs and CFIs. Finally, the paper builds upon the existing research work on the CG effects for different types of financial institutions by proposing a single regression based analytical framework for comparing the effects across two different types of institutions, harvesting the benefits of higher degrees of freedom and avoiding/minimizing the measurement error. [ABSTRACT FROM AUTHOR]

We used the generalized propensity score method to estimate the differential effects of five Early Child Care and Education (ECCE) experiences (Prekindergarten, Head Start, Center-based Child Care, Home-based Child Care, and Parental Care) in reducing math and reading achievement gaps between boys versus girls, Latinx versus Whites, and Blacks versus Whites. Findings revealed differential effects of ECCE in reducing gender and racial achievement gaps. However, results indicated that significant gender and racial gaps still exist despite ECCE experiences and that these gaps widen throughout the elementary and middle school years. [ABSTRACT FROM AUTHOR]

Objectives: Meditation encompasses a variety of techniques, but little is known on how and for whom they work. This study explored potential mechanisms of four different meditation techniques in beginners and which technique might be suited for whom. Method: Using an experimental single-case design, we compared the longitudinal effects of concentrative, humming, observing-thoughts, and walking meditation. Forty-four healthy participants without meditation experience were randomly assigned to one of the four techniques and 42 completed the treatment. Following a baseline period of 2 to 4 weeks, participants learned and practiced their technique 20 min daily for 6 to 8 weeks and completed daily online questionnaires throughout the entire study period. At pretest, we assessed participants' motivation and personality. We analyzed the data visually and by conducting single-case meta-analyses, correlation, and multivariate analyses. Results: Body awareness, decentering, and emotion regulation improved reliably and continuously over time, for all four techniques. Thus, these processes could represent common mechanisms for novice meditators. Walking meditation led to the smallest improvements in decentering and mind-wandering, but the highest in body awareness and emotion regulation. Individuals varied in response to the treatment. The two "classic" techniques (concentration, observing-thoughts) led to more consistently positive multivariate response patterns and to better responses in participants high in neuroticism. In contrast, those high in extraversion benefitted more from the two unusual ones (humming, walking). We additionally observed interesting interactions with different motivational reasons. Conclusions: With this study, we hope to contribute to theory building and answering two urgent questions—what the key mechanisms of meditation are and who benefits most from what kind of practice. [ABSTRACT FROM AUTHOR]

Improvements in substance use disorder recovery may be achieved by recognizing that effective interventions do not work equally well for all individuals. Heterogeneity of intervention effects is traditionally examined as a function of a single variable, such as gender or baseline severity. However, responsiveness to an intervention is likely a result of multiple, intersecting factors. Latent class moderation enables the examination of heterogeneity in intervention effects across subgroups characterized by profiles of characteristics. This study analyzed data from adolescents (aged 13 to 18 years old) who needed treatment for cannabis use (n = 14,854) and participated in the Global Appraisal of Individual Needs to evaluate differential effects of substance use services on cannabis use outcomes. We demonstrate an adjusted three-step approach using weights that account for measurement error; sample codes in Mplus and Latent Gold are provided and data are publicly available. Indicators of the latent class moderator comprised six contextual (e.g., recovery environment risk) and individual (e.g., internal mental distress) risk factors. The latent class moderator comprised four subgroups: low risk (21.1%), social risk (21.1%), environmental risk (12.5%), and mixed risk (45.2%). Limited moderation of associations between level of care and any past 90-day cannabis use were observed. In predicting number of cannabis use-days, compared to individuals with low risk, those with environmental risk showed improved outcomes from intensive outpatient care whereas individuals with social risk and mixed risk showed improved outcomes from residential care (all compared to early intervention/outpatient care). Latent class moderation holds potential to elucidate heterogeneity in intervention effectiveness that otherwise may go undetected. [ABSTRACT FROM AUTHOR]

Purpose: The objective of this paper is threefold. First, it aims to empirically study whether firm-specific/idiosyncratic uncertainty, macroeconomic/aggregate uncertainty and political uncertainty have an adverse influence on firms' investment decisions in Pakistan. After establishing this, it scrutinizes whether the uncertainty effects on investment are different for firms of different sizes. Finally, it investigates whether any heterogeneity exists in the uncertainty impacts across different industries. Design/methodology/approach: The empirical analysis is based on an unbalanced panel data of 468 nonfinancial firms listed at the Pakistan Stock Exchange (PSX) during the period 2000–2018. Departing from the literature, the paper builds a time-varying composite volatility/uncertainty index based on the principal component analysis (PCA) by utilizing the constructed volatility series for sales, cash flows and return on assets to gauge firm-specific uncertainty for each firm included in the analysis. Likewise, the paper develops a PCA-based composite index for macroeconomic uncertainty by using the conditional variance series of consumer price index (CPI), industrial production index (IPI), the interest rate and the exchange rate obtained by estimating the (generalized) autoregressive conditional heteroscedastic, (G)ARCH, models. Finally, political uncertainty is measured by political risk components maintained by the Political Risk Services Group. The empirical framework of the paper augments the standard investment equation by incorporating all three types of uncertainty. Firms are grouped into small, medium and large categories based on firms' total assets and the size indicators are generated. Next, the indicators are multiplied by each uncertainty measure to quantify the differential effects of uncertainty across firm size. Firms are also differentiated by sectors to explore the sector-based asymmetries in the uncertainty effects. The "robust two-step system generalized method of moments (2SYS GMM) (dynamic panel data) estimator" is applied to estimate the empirical models. Findings: The results provide robust and strong evidence of the detrimental influence of all three types of uncertainty on investment. Yet, it is observed that the strength of the influence considerably varies across uncertainty types. In particular, compared to firm-specific uncertainty, both macroeconomic and political uncertainties have more unfavorable effects. The analysis also reveals that the effects of all three types of uncertainty are quite different at small, medium and large firms. Specifically, it is observed that although the investment of all firms is influenced adversely by magnified uncertainty, the adverse effects of all three kinds of uncertainty are quite stronger at small firms than medium and large firms. These findings support the phenomenon of size-based asymmetries in the effects of uncertainty on investment. The results also provide evidence that either type of uncertainty quite differently affects the investment policy of firms in different sectors. Practical implications: The findings help different stakeholders to know how different types of uncertainty differently affect corporate firms' investments. Further, they suggest that firm size has a vital role in ascertaining the adverse effects of uncertainty on investment. The paper identifies to which type of uncertainty investors and policymakers should care more about and to which types of firms and industries they should concern more during volatile times. Firms should have more fixed assets and expand their size to mitigate the detrimental effects on investment of internal and external uncertainties. The government should enhance the political stability to induce firms for a higher level of investment, which, in turn, will result in higher growth of the economy. Originality/value: The originality of the paper is credited to four aspects. First, unlike most previous studies that have utilized a single volatility measure, this paper constructs composite uncertainty indices based on the weights determined by the PCA. Second, it examines the effect of political uncertainty over and above the effects of idiosyncratic and aggregate (macroeconomic uncertainty) for an emerging economy. Third, and most important, it provides first-hand empirical evidence on the role of firm size in establishing the asymmetric effects of uncertainty on investment. Finally, it provides evidence on the industry-based heterogeneity in the uncertainty effects. [ABSTRACT FROM AUTHOR]

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Copyright of Lernen und Lernstörungen is the property of Hogrefe AG and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Traditionally, yoga is a multicomponent practice consisting of postures, breathing techniques, meditation, mantras, and ethics. To date, only a few studies have tried to dismantle the effects of each of these components and their combinations. To fill this gap, we examined the incremental effects of ethical education and physical Hatha yoga on mantra meditation using a single-case multiple-baseline design. This study was part of a project evaluating the new mind–body program Meditation-Based Lifestyle Modification. Fifty-seven healthy participants with no regular yoga or meditation practice were randomly assigned to three baselines (7, 14, and 21 days) and four conditions using a random number generator. The conditions were mantra meditation alone (MA), meditation plus physical yoga (MY), meditation plus ethical education (ME), and meditation plus yoga and ethical education (MYE). All the interventions lasted for 8 weeks and were run consecutively according to baseline length. During the baseline and treatment phases, participants received daily questionnaires measuring their well-being (WHO-5 Well-Being Index), stress (Perceived Stress Scale), and subjective experiences. Forty-two participants completed the treatment and were entered in the analyses. We analyzed our data using visual inspection, effect size estimation (Tau- U), and multilevel modeling. Almost all participants showed a longitudinal increase in well-being. Regarding between-group differences, participants who received ethical education exhibited the largest increases in well-being (Tau- U = 0.30/0.23 for ME/MYE), followed by participants in the MY condition (Tau- U = 0.12). Conversely, participants in the MA condition showed no change (Tau- U = 0.07). There was a tendency for the combined treatments to decrease stress. This tendency was strongest in the MY condition (Tau- U = –0.40) and reversed in the MA condition (Tau- U = 0.17). These results emphasize the incremental and differential effects of practicing meditation in combination with other practices from the eight-fold yoga path. This approach is valuable for better understanding the multifaceted practice of yoga. Clinical Trial Registration: www.ClinicalTrials.gov, identifier: NCT04252976. [ABSTRACT FROM AUTHOR]

In regression analysis, the data sample is often composed of diverse sub-populations such as ethnicities and geographical regions. In multiple application areas, it is important to identify the groups where each covariate has a positive, negative or null impact on the response. If the number of sub-populations is small, a full interaction model may be fit with group-specific covariate effects. However, if the number of groups is very large, for example, hospitals or other clustering units, such a model is not identifiable. Therefore, we propose a prior distribution which combines the information across sub-populations with a similar covariate effect. This Bayesian analysis of differential effects (BADE) classifies the group-specific covariate effects as positive, negative or null. Besides allowing the analysis of differential effects for many sub-populations, the proposed approach improves substantially the identification of important interactions in cases with few groups. This is illustrated via simulations. The procedure is motivated on, and applied to, a large study related to patients' satisfaction with hospitals, where we show that classifying group-specific covariate effects based on methods such as mixed-effects models may be strongly misleading. [ABSTRACT FROM AUTHOR]

This observational study examined treatment satisfaction (TS) following routine outpatient cognitive-behavioral therapy (CBT) in a large sample of children (n = 795; aged 6 to 10 years). TS was investigated in parent and therapist rating. Means, standard deviations and inter-rater correlations were calculated to investigate TS. Regression analysis was conducted to examine potential correlates of TS (patient-related variables, mental disorder characteristics, socio-demographic factors and treatment variables). High TS in parent and therapist rating was found, with therapists showing a lower degree of TS than parents (completely or predominantly satisfied: parent rating 94.1%, therapist rating 69.5%). A statistically significant, moderate inter-rater correlation was found. Regression analysis explained 21.8% of the variance in parent rating and 57.2% in therapist rating. Most of the TS variance was explained by mental disorder characteristics (parent-rated symptoms and therapist-rated global impairment at treatment end) and by treatment variables (especially the therapist-rated cooperation of parents and patients), whereas socio-demographic and patient-related variables did not show any relevant associations with TS. Based on these results, to optimize TS, therapists should concentrate on establishing a sustainable cooperation of parents and children during therapy, and work to achieve a low global impairment at treatment end. [ABSTRACT FROM AUTHOR]

While linear models remain the backbone of human resource development (HRD) as well as broader social science research, they are limited by their inability to detect curvilinearity or changes in direction and, therefore, may not accurately represent the nature of relationships between variables. This paper advocates the utility of the Andrews' (1993) threshold effect technique in the HRD, work, organization, and employment study literatures and does so using the gender wage gap as an illustration. The analysis compares traditional linear regression, a curvilinear quadratic model, and the threshold effect technique using publicly available wage data. This article demonstrates how the threshold method permits the data to organically determine the location of a critical break point, should one exist, and how it addresses the problem of overlooked relationships due to traditional linear assumptions. An overview of the technique and related coding is provided for researchers interested in broadening their analytical arsenal to enhance the study of the gender wage gap as well as other human‐resource‐related phenomena. [ABSTRACT FROM AUTHOR]

Colorectal cancer (CRC) does not affect different sociodemographic groups uniformly. CRC screening programmes could seek to reduce this inequality; however, the screening programmes themselves might be subject to differential participation across sociodemographic groups. This study investigates the sociodemographic inequality at all steps in Denmark's nationwide CRC screening programme: screening participation, faecal immunochemical test (FIT) results, colonoscopy compliance, CRC diagnosis, and cancer stage. This cohort study includes all first-time invitees from the beginning of the Danish population-based CRC screening programme from 1 March 2014 to 31 December 2017. Sixty-four percent of the invitees participated in the screening programme, and of those 7% were FIT-positive. After being invited to further diagnostic procedures, 90% responded to the invitation, and among those 5% were CRC-positive. Among those diagnosed with CRC, 9% were stage IV. Through multivariable analyses, we identified sociodemographic inequalities in all steps of the screening programme from returning a stool sample to being diagnosed with CRC. Specifically, we identified inequalities across sex, age, migration status, relationship status, the screening status of one's partner, education, income, and use of health services. Women were more likely to participate compared to men (RR = 1.13; 95% CI: 1.12–1.13), but had a lower risk of a positive FIT result (RR = 0.67; 95% CI: 0.66–0.68) and of a CRC diagnosis (RR = 0.88; 95% CI: 0.82–0.93) compared to men. The likelihood of participating as well as the risk of positive FIT results and CRC diagnosis increased with age. All steps of the screening programme were subject to sociodemographic inequalities. Interventions are needed to target groups identified as having lower uptake as well as high-risk of being FIT- and/or CRC-positive. These groups include males, individuals aged 60+ years and individuals who do not visit their GP regularly. [ABSTRACT FROM AUTHOR]

This paper examines the child development outcomes of two cohorts of children who were exposed to the same intervention at different points in time. One cohort was eligible to access playgroups during the first year of a five-year project cycle, beginning at age four. The other cohort became eligible to access these services during the third year of a five-year project cycle, beginning at age three. The younger cohort was more likely to be exposed to playgroups for longer and at more age-appropriate times relative to the older cohort. The paper finds that enrollment rates and enrollment duration in preprimary education increased for both cohorts, but the enrollment effects were larger for the younger cohort. In terms of child development outcomes, there were short-term effects at age five that did not last until age eight, for both cohorts. Moreover, the younger cohort had substantially higher test scores during the early grades of primary school, relative to the older cohort. We document the extent to which program impacts can vary as a result of differences in project implementation. [ABSTRACT FROM AUTHOR]

Background: The current set of pre‐registered studies tested the effect of savoring a high‐arousal (exciting) or low‐arousal (calm) positive experience on help‐seeking intentions among people with heightened depressive symptomatology. Methods: Across all three studies, participants with heightened depressive symptomatology who had not yet sought help were randomly assigned to complete a 6‐minute writing task where they reflected on an exciting memory, a calm memory, or what they did today and yesterday. Results: Savoring an exciting memory was associated with significantly greater arousal than savoring a calm memory and the control condition (Study 1; N = 218). Both savoring conditions were associated with greater positive emotion than the control condition (Study 2; N = 193). In Study 3 (N = 1,238), savoring an exciting memory, when compared to the control condition, increased help‐seeking intentions, whereas savoring a calm memory did not. Conclusions: The current studies support the use of high‐arousal, rather than low‐arousal, positive emotions to increase help‐seeking intentions among people with depression. [ABSTRACT FROM AUTHOR]

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Allelopathy has been applied to control nuisance algae in aquatic systems, but the effects of allelochemicals on the broad spectrum of algae are not well understood. We investigate algicidal effects of the allelochemical juglone on the bloom-forming, harmful algae Microcystis aeruginosa and Stephanodiscus hantzschii, and on several non-target algal species including cyanobacteria (Anabaena flos–aquae, Oscillatoria curviceps, and Phormidium subfuscum), diatoms (Asterionella formosa, Fragilaria crotonensis, and Synedra acus), and green algae (Chlorella vulgaris, Scenedesmus ecornis, and Scenedesmus quadricauda), in laboratory and field enclosure bioassays. Under three treatment concentrations (0.01, 0.1, and 1 mg L−1) of juglone, Microcystis cell density is significantly reduced by 35–93%. Concentrations of 0.1 and 1 mg L−1 inhibits Stephanodiscus growth almost equally (66% and 75%, respectively). To contrast, juglone produces a stimulatory allelopathic effect on three green algae, and other tested diatoms showed hormesis. Overall, the cyanobacteria are more sensitive to juglone than the green algae and diatoms. These results indicate that the allelopathic effects of juglone on microalgae vary depending on their characteristic cellular morphology and anatomy. [ABSTRACT FROM AUTHOR]

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This study aimed to examine the impact of a universal, school-based intervention, the Good Behavior Game (GBG), on children's behavior, and to explore any subgroup moderator effects among children at varying levels of cumulative risk (CR) exposure. A 2-year cluster-randomized controlled trial was conducted comprising 77 primary schools in England. Teachers in intervention schools delivered the GBG, whereas their counterparts in control schools continued their usual provision. Behavior (specifically disruptive behavior, concentration problems, and pro-social behavior) was assessed via the checklist version of the Teacher Observation of Classroom Adaptation. A CR index was calculated by summing the number of risk factors to which each child was exposed. Multilevel models indicated that no main or subgroup effects were evident. These findings were largely insensitive to the modeling of CR although a small intervention effect on disruptive behavior was found when the curvilinear trend was used. Further sensitivity analyses revealed no apparent influence of the level of program differentiation. In sum, our findings indicate that the GBG does not improve behavior when implemented in this sample of English schools. [ABSTRACT FROM AUTHOR]

The OLS and ordered probit estimation of a causal relationship between income and happiness assume linearity in individual and average income effects and the same average effect holds over the entire range of subjective well-being distribution. The response of well-being to income changes is not the same for poor and rich, dissatisfied or unhappy, and satisfied or happy people. This paper estimates heterogeneity in the income-life satisfaction relationship at specific locations of subjective well-being distribution by panel quantile regression method. The data is derived from six waves of the World Value Survey for 12 major states of India for 24 years over the period 1990-2014. The descriptive analysis of well-being distribution across states shows heterogeneity in the income-well-being relationship between states and individuals within states. The across-states over-time panel quantile regression results reveal that estimation of average effect only provides an incomplete picture of the effect of income at both ends of the conditional distribution of well-being indicators, life satisfaction and happiness levels. The quantile regression estimates vastly differ not only from the mean estimates, but also across quantiles. Life satisfaction falls and happiness rises with an increase in average state income and the income effect is strong at the lower end than at the upper end of subjective well-being distribution. [ABSTRACT FROM AUTHOR]

Most often the social comparison or relative income hypothesis has been used as an explanation for the lack of systematic relationship between income and happiness, using the ordered probit regression method. The identification of relevant reference group and the estimation of the differential effects of comparison income have been controversial. To overcome these twin issues, this paper uses an ordinal comparison income approach based on rich/poor dichotomy and rank income. The rank income of an individual is defined as his relative position in the income distribution within the reference group and the average income of the reference group is used to define the rich/poor classification. The differential effects of ordinal incomes across life satisfaction distribution is estimated by the panel fixed effects ordered profit regression model using the WVS data for India. The estimated results show that ordinal income comparison, rather than cardinal average reference income, is a better predictor of life satisfaction levels. Raising income level is relatively important for less satisfied people while increasing rank status is important for highly satisfied people in India. [ABSTRACT FROM AUTHOR]

Cold atmospheric pressure plasma (CAP) is widely used in research for biomedical applications and is a promising therapy to selectively eradicate cancer cells. However, there is no unity for the species that cause this different effect. The aim of this article was to further determine the key reactive species causing differences in viability between melanoma cells (B16) and fibroblasts (L929). In this article, the cell viability of two cell lines exposed directly to the CAP was tested. The result shows CAP exhibit different cytotoxicity against the viability of two cell lines. The proliferation of B16 cells is significantly inhibited. By using superoxide anions scavengers and catalase, long-lived reactive oxygen species (ROS) generated by CAP, such as hydrogen peroxide (H2O2), were found to have stronger cytotoxicity to B16. Besides, the B16 cells were significantly inhibited after simultaneously scavenging free radicals and hydrogen peroxide, while it has the opposite effect on L929 cells. In order to explore whether there may be other long-lived species, such as protein oxides, which have important effects on cells, CAP-treated bovine serum albumin (BSA) was applied in cultured cells. We observed the inhibition effect of CAP-treated BSA on the growth of B16 but proliferation versus L929 cells. The content of peroxide in CAP-treated BSA was measured by xylenol orange method. The rate of peroxide reduction in B16 cells is faster than that of L929 cells. In addition, after adding certain enzymes to cells, the effects of CAP on intracellular ROS generation were examined by liquid chromatography $/$ mass spectrometry (LC/MS). There is a significant difference in the content of $\mathrm {O}_{{2}}^{ {\cdot -}}$ and H2O2 in the two cells. [ABSTRACT FROM AUTHOR]

In recent decades, several countries have made an effort to increase the enrollment rates and performance of students in science and mathematics by means of mandatory, rigorous course work, which is often referred to as curricular intensification (CI). However, there is a lack of research on intended and unintended effects of CI reforms on achievement and motivation. Using representative data from the National Educational Panel Study, we examined effects of a prototypical CI reform in 1 German state. We compared data from the last student cohort before and the first student cohort after the reform at the end of upper secondary school. There was no statistically significant effect on average achievement. However, we found first evidence for differential effects on English reading and a higher English self-concept of young men after the reform, whereas the reform had a negative effect on young women's math self-concept. [ABSTRACT FROM AUTHOR]

Despite the systematic recognition of large gender gaps in favour of boys in mathematics performance in Chile, the role of schools in explaining this gap has been comparatively underresearched. This paper analyses a longitudinal dataset to explore within- and between-school variation of Chilean primary schools in promoting attainment and progress of girls and boys. In order to reflect the hierarchical nature of the educational data, multilevel modelling is used, with 163,044 students, nested within 3,355 schools, within 310 municipalities to fit raw, contextualised attainment, and value-added models. The weak evidence indicative of gender differential school effect in progress in Chilean primary schools was interpreted as non-substantive. However, differences in effectiveness played a significant role, as girls progressed more than boys in less effective schools, but the opposite was true in more effective schools. Finally, the study concludes that the Chilean gender gap needs to be addressed mainly beyond schools. [ABSTRACT FROM AUTHOR]

Destructive leadership comes in many shapes and forms. From reviewing the literature, we conclude that three major forms of destructive leader behaviors are described: (1) follower-directed destructive behaviors, i.e., genuine abusive forms of destructive leadership, (2) organization-directed behaviors, i.e., behaviors such as stealing from the organization or embezzlement, and (3) self-interested destructive leader behavior, i.e., leader who exploit others to reach their goals. One can easily imagine that these three types of leader behavior have very different effects on followers. Unfortunately, so far, there is no empirical evidence to support this, since comparative research in the field of destructive leadership is scarce. With this paper, we aim to address this gap: In two studies, an experimental and a field study, we examine the differential impact of these three different destructive leader behaviors on two important outcomes: first, their impact on different emotional reactions of followers, the most proximal outcome to a social interaction. Second, we examine a key outcome in leadership research: followers' turnover intention. The results suggest that different types of destructive leader behavior do impact followers differently. Whereas all three behaviors had a positive relationship with negative affect, follower-directed destructive behaviors had the strongest relation out of the three. As expected, all three types of destructive behavior relate to turnover intention, yet, the results of our study suggest that different types of destructive leader behavior relate to different urgencies of turnover intention. We conclude that a tailored approach to destructive leadership, whether in research or practice, seems necessary, as diverse types of destructive leader behaviors affect employees differentially. [ABSTRACT FROM AUTHOR]

Objective: To examine whether different measures of social disconnectedness—subjective loneliness, network quality, network size, living alone—have differential effects on the health of older adults. Methods: We used a longitudinal sample of the German Aging Survey (N = 4,184) and analyzed seven measures of health (life satisfaction, positive affect, negative affect, depression, cognitive performance, physical functioning, and pulmonary function) via regression analyses. Results: We found that subjective loneliness and network quality best predicted mental health; contrarily, network size and living alone best predicted physical and cognitive health. Discussion: Different measures of social disconnectedness have differential effects on health. Therefore, using only global measures or one aspect of social disconnectedness might obfuscate potential health hazards. Researchers and practitioners should be mindful of differences between these measures and should include multiple aspects of social disconnectedness in their research and practice. Future studies should explore the causes why these measures and their effects differ. [ABSTRACT FROM AUTHOR]

The authors examined differential effects of interim assessments on minority and low socioeconomic status students' achievement in Grades K–6. They conducted a large-scale cluster randomized experiment in 2009–2010 to evaluate the impact of Indiana's policy initiative introducing interim assessments statewide. The authors used 2-level models to analyze the single-grade data and determine whether interim assessments interacted with student ethnicity, socioeconomic status, gender, or school composition (i.e., percent of minority or disadvantaged students). The authors also combined estimates across grades using fixed effects meta-analysis. Results indicated little evidence about differential effects. The majority of interaction estimates were insignificant and close to zero. There is some indication that in Grades K–2 Indiana's interim assessment may have closed the Hispanic–White gap in reading. In kindergarten and Grade 3 the treatment may have widened the gap between schools with higher and lower percentages of minority students and may have reduced the gap between schools with higher and lower percentages of economically disadvantaged students in mathematics. [ABSTRACT FROM AUTHOR]

Supply chain security (SCS) breaches (a form of supply chain risk) are distressing supply chains and they have the potential to engender acute pain on the society at large. To counteract such breaches, international bodies, nations, societies, industries, and firms have instituted several countermeasures in the form of standards and respective practices. Given that not all incidences/breaches can be averted, the risk management literature advocates that firms should adopt practices that can thwart incidences/breaches and practices that can provide a swift response once an incident/breach is detected in order to contain damages, ease the pain, and restore operations. Resting on the risk management literature and interactions with professionals, we classify SCS management practices into four categories based on their intent (i.e., detection, prevention, response, and mitigation) and operationalize each via multiple indicators. We then test the relative efficacy of these practices to explain SCS performance using responses from 462 firms operating in the United States and Italy. [ABSTRACT FROM AUTHOR]

Purpose This paper aims to empirically assess the contribution of Islamic banks toward the financial stability of Pakistan. For this, the authors investigate the relative financial strength of Islamic banks and their contribution toward the financial stability. They also examine the relationship between the competitive conduct of banks and banking system stability.Design/methodology/approach The authors use quarterly data of ten conventional banks, four full-fledged Islamic banks and six standalone Islamic branches of conventional banks of Pakistan for the period 2006-2012. The z-score has been computed and used as the measure of stability of banks and the random effects estimator applied to quantify the impact of bank-specific variables and macroeconomic indicators on the financial stability. The empirical framework used in the paper enables the authors us to examine the differential effect of each underlying variable on the financial stability across Islamic and conventional banks. To check the robustness of the results, the authors have estimated several models with different specifications.Findings The regression results indicate that income diversity, profitability ratio, loan to asset ratio, asset size and the market concentration ratio of banks have significant effects on the stability of banks. Comparing Islamic and conventional banks, notable differential effects of the empirical determinants of financial stability for Islamic and conventional banks have been observed. The results suggest that Islamic banks have performed better as compared to conventional banks and contributed more effectively in the stability of financial sector. Overall, the results depict that the contribution of Islamic banks toward the financial stability has been reasonable and prospective.Practical implications The empirical results of the paper are very useful not only for banks’ managements but also for the investors, bank customers and policymakers. Specifically, the findings help in enhancing our understanding as to how the bank-specific variables and macroeconomic indicators are related to the financial stability of the banking system. The results also help understand the role of both Islamic and conventional banks in the financial stability. Further, the results suggest that the financial soundness can be enhanced by creating healthy competition in the banking industry. The results about macroeconomic indicators imply that protective measures are required to intensify (mitigate) the positive (negative) effect of gross domestic product (inflation) on banks’ financial stability.Originality/value This paper provides an overall comparative analysis of financial stability of both Islamic and conventional banks of Pakistan. First, the paper computes the z-score for each bank included in the sample, and then, it performs the regression analysis to study how bank-specific variables and macroeconomic factors are related to the financial stability of banks. Unlike the previous studies, our empirical framework enables the authors to examine the differential effect of each underlying variable on the financial stability across Islamic and conventional banks. [ABSTRACT FROM AUTHOR]

Regression mixture models are a novel approach to modeling the heterogeneous effects of predictors on an outcome. In the model-building process, often residual variances are disregarded and simplifying assumptions are made without thorough examination of the consequences. In this simulation study, we investigated the impact of an equality constraint on the residual variances across latent classes. We examined the consequences of constraining the residual variances on class enumeration (finding the true number of latent classes) and on the parameter estimates, under a number of different simulation conditions meant to reflect the types of heterogeneity likely to exist in applied analyses. The results showed that bias in class enumeration increased as the difference in residual variances between the classes increased. Also, an inappropriate equality constraint on the residual variances greatly impacted on the estimated class sizes and showed the potential to greatly affect the parameter estimates in each class. These results suggest that it is important to make assumptions about residual variances with care and to carefully report what assumptions are made. [ABSTRACT FROM AUTHOR]

Tissue-type plasminogen activator (tPA) a serine protease is constituted of five functional domains through which it interacts with different substrates, binding proteins, and receptors. In the last years, great interest has been given to the clinical relevance of targeting tPA in different diseases of the central nervous system, in particular stroke. Among its reported functions in the central nervous system, tPA displays both neurotrophic and neurotoxic effects. How can the protease mediate such opposite functions remain unclear but several hypotheses have been proposed. These include an influence of the degree of maturity and/or the type of neurons, of the level of tPA, of its origin (endogenous or exogenous) or of its form (single chain tPA versus two chain tPA). In this review, we will provide a synthetic snapshot of our current knowledge regarding the natural history of tPA and discuss how it sustains its pleiotropic functions with focus on excitotoxic/ischemic neuronal death and neuronal survival. [ABSTRACT FROM AUTHOR]

Research increasingly emphasizes understanding differential effects. This article focuses on understanding regression mixture models, which are relatively new statistical methods for assessing differential effects by comparing results to using an interactive term in linear regression. The research questions which each model answers, their formulation, and their assumptions are compared using Monte Carlo simulations and real data analysis. The capabilities of regression mixture models are described and specific issues to be addressed when conducting regression mixtures are proposed. The article aims to clarify the role that regression mixtures can take in the estimation of differential effects and increase awareness of the benefits and potential pitfalls of this approach. Regression mixture models are shown to be a potentially effective exploratory method for finding differential effects when these effects can be defined by a small number of classes of respondents who share a typical relationship between a predictor and an outcome. It is also shown that the comparison between regression mixture models and interactions becomes substantially more complex as the number of classes increases. It is argued that regression interactions are well suited for direct tests of specific hypotheses about differential effects and regression mixtures provide a useful approach for exploring effect heterogeneity given adequate samples and study design. [ABSTRACT FROM AUTHOR]

This study examines the effects of watching TV debates on voters' learning. Analyzing panel survey data conducted in the 2012 South Korean presidential election, we test whether voters learn about candidates through viewing presidential debates. In particular, this study finds that the information effects of watching TV debates are differential across individuals depending on their levels of political knowledge. The findings of this study show that viewing TV debates positively affects learning in general. Individuals are more likely to assimilate information through viewing televised debates if they watch TV debates more often and pay more attention to televised debates. Furthermore, this study reveals that the learning effects are heterogeneous across individuals according to their political knowledge. Citizens who are politically less knowledgeable, for instance, tend to learn more about candidates' campaign proposals through viewing televised debates. [ABSTRACT FROM AUTHOR]

This review integrates findings from studies formally testing moderators of parenting interventions targeting child conduct problems from ages 1 to 10 with a focus on baseline child problem behavior, sociodemographic risks, and family process risks as moderators. The review examines whether differential effectiveness has been found for individuals at higher versus lower risk across the body of moderator studies of parenting interventions. We conclude that greater problematic child behavior at baseline may, in some cases, be associated with greater benefit from parenting interventions. None of these studies reviewed found reduced effects for those with higher baseline child problem behavior. With regard to sociodemographic and family process risks as moderators, findings are less consistent; however, on the whole, the collection of studies suggests equal effectiveness across levels of risk, with reduced effects for those at higher risk rarely demonstrated. Implications of these conclusions for future research and intervention efforts are discussed. [ABSTRACT FROM AUTHOR]

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This study examines the impact of offenders’ psychological and demographic attributes and their offense history on the effectiveness of Reasoning and Rehabilitation, a cognitive–behavioral intervention. Differential effects were examined for a sample of 940 male parolees randomly assigned to either experimental or comparison conditions. The study used survival analysis to test interactions between treatment and age, race, social class, risk, marital status, prearrest employment status, education, prior violence, interpersonal maturity level, personality, reading level, and IQ. For the entire sample, the difference in recidivism rates (returns to prison up to 33 months) was not statistically significant. The analysis of differential effects, however, uncovered five interaction effects. The treated high-risk, aged 28 to 32 years, assessed as dependent (Jesness Inventory [JI]), and White groups evidenced lower recidivism rates than their comparison group. The treated parolee group assessed with high anxiety (JI) evidenced a higher recidivism rate than their comparison group. [ABSTRACT FROM AUTHOR]

The current study examines the impact of alternative education on children's early school engagement in terms of school enjoyment and independent participation. A sample of 2,776 children from traditional (e.g., mainstream) and alternative (Freinet and Waldorf) Flemish schools was followed from their 3rd year of kindergarten until 3rd grade. The present study does not evidence a positive effect of alternative education on school engagement. In contrast, it was found that in alternative education children acted less independent compared to traditional schools. Furthermore, differential effects in terms of children's socioeconomic status and initial language achievement are explored. In alternative schools, children's initial level of language achievement tends to be less determinative for their school engagement compared to traditional schools. [ABSTRACT FROM PUBLISHER]

Linear regression and its variants like analysis of variance are arguably the most widely used statistical techniques in psychology. By using linear regression it is merely assumed rather than empirically tested that the effects of the predictor variables are linear and homogeneous across the distribution of the dependent variable. This is problematic because it biases a scientist's reasoning and hinders possible practical and theoretical insights. Thus an important question to ask is: Are the effects studied by psychologists really linear and homogeneous? Generalized additive models (GAMs) and quantile regression can be used to pursue this question. Benefits of complementing linear regression with these approaches include the ability to tailor actions on the specific individual in practice and the opportunity to gain more advanced scientific knowledge, for example about non-linear effects. The use of GAMs and quantile regression is furthermore empirically demonstrated in an analysis of risk-seeking and criminal peer networks as predictors of violent crime in a representative sample of German youth (N = 44.610). Practical and theoretical consequences of the results are discussed. Psychological science could immensely benefit from studying non-linear and heterogeneous effects. [ABSTRACT FROM AUTHOR]

Mild to moderate skew in errors can substantially impact regression mixture model results; one approach for overcoming this includes transforming the outcome into an ordered categorical variable and using a polytomous regression mixture model. This is effective for retaining differential effects in the population; however, bias in parameter estimates and model fit warrant further examination of this approach at higher levels of skew. The current study used Monte Carlo simulations; 3000 observations were drawn from each of two subpopulations differing in the effect ofXonY. Five hundred simulations were performed in each of the 10 scenarios varying in levels of skew in one or both classes. Model comparison criteria supported the accurate two-class model, preserving the differential effects, while parameter estimates were notably biased. The appropriate number of effects can be captured with this approach but we suggest caution when interpreting the magnitude of the effects. [ABSTRACT FROM AUTHOR]

Background: In contrast with an early implicit "facilitative hypothesis" of humor, a revised specificity hypothesis predicts that the benefits of humor depend on the specific style of humor used. Information on predictors of these humor styles in turn enhances the ability to predict the effect on well-being. Methods: We examined the relationships between interpersonal competence, self-esteem, and different styles of humor, while also examining the contributions of age and gender. Participants (n = 201) aged 18-63 years completed the Rosenberg Self-Esteem Inventory, the Interpersonal Competence Questionnaire, and the Humor Styles Questionnaire, and gave demographic information. Results: High self-esteem was associated with higher use of affiliative, aggressive, and self-enhancing humor styles, but lower use of self-defeating humor. High interpersonal competence predicted greater use of affiliative humor, whereas low interpersonal competence predicted greater use of aggressive humor. Further analyses showed that initiation competence predicted affiliative humor (positively) but both initiation competence (positively) and conflict management competence (negatively) predicted aggressive humor. Conclusion: The findings that both self-esteem and initiation competence contribute to use of aggressive humor add to knowledge of who is likely to use this potentially harmful humor style. We conclude that a readiness to initiate humorous interactions is not on its own a general and positive attribute contributing to "good" humor. [ABSTRACT FROM AUTHOR]

The processes around the identification of special educational needs (SEN) should mean that those pupils who need most help receive it. However, there are concerns that this process is not working and there is an over-identification of pupils with SEN. Previous international research has shown that summer-born children are more likely to be identified as having SEN. However, these studies tend to treat SEN as a homogenous group. In this paper, we explore the extent to which the month-of-birth effect can be seen in subgroups of SEN. A survey of 450 schools in England was undertaken to explore the levels of provision and categories of SEN for 15,640 pupils. This led to differential month-of-birth effects being noted in category of SEN, with moderate learning difficulties being most susceptible. We hypothesise that teachers may be labelling younger children within the year group on the basis of political aspirations of attainments to be reached by the end of the academic year. When more thorough, multiprofessional assessments are undertaken, the month-of-birth effect is no longer evident. This has clear implications for assessment; identification; allocation of scarce educational resources; for educational policy on monitoring school performance and initial teacher training. [ABSTRACT FROM AUTHOR]

Regression mixture models, which have only recently begun to be used in applied research, are a new approach for finding differential effects. This approach comes at the cost of the assumption that error terms are normally distributed within classes. This study uses Monte Carlo simulations to explore the effects of relatively minor violations of this assumption. The use of an ordered polytomous outcome is then examined as an alternative that makes somewhat weaker assumptions, and finally both approaches are demonstrated with an applied example looking at differences in the effects of family management on the highly skewed outcome of drug use. Results show that violating the assumption of normal errors results in systematic bias in both latent class enumeration and parameter estimates. Additional classes that reflect violations of distributional assumptions are found. Under some conditions it is possible to come to conclusions that are consistent with the effects in the population, but when errors are skewed in both classes the results typically no longer reflect even the pattern of effects in the population. The polytomous regression model performs better under all scenarios examined and comes to reasonable results with the highly skewed outcome in the applied example. We recommend that careful evaluation of model sensitivity to distributional assumptions be the norm when conducting regression mixture models. [ABSTRACT FROM PUBLISHER]

The guidelines published by the National Association for the Education of Young Children on the use of developmentally appropriate practices (DAP) have, over the last two decades, had an important influence on young children's educational experiences. The efficacy of these guidelines for changing children's outcomes has been examined by only a handful of studies and with mixed results. This study looks at the effects of classroom and school-level use of classroom elements of DAP in 1st, 2nd, and 3rd grades on parent ratings of children's social skills at the end of the year, controlling for ratings of the same construct at the end of the previous year, gender, and ethnicity with a sample of between 1,145 and 2,111 students each year. Differential effects of DAP for males and females and for children of different ethnic backgrounds also were examined. Despite high power, no consistent effects of DAP were observed and no interactions found, suggesting that DAP does not affect parents' ratings of social skills in 1st through 3rd grades. The importance of these results, in light of other work on the effects of DAP, is discussed. [ABSTRACT FROM PUBLISHER]

Purpose – This study aims to examine grocery shoppers' beliefs about store attributes as antecedents to shopping value by exploring whether dimensions of store attribute beliefs have differential effects (i.e. strength and direction) on hedonic versus utilitarian shopping value. Design/methodology/approach – Shoppers at three grocery outlets in a Norwegian city were approached. After they had agreed to participate in the survey, they received a package containing an information letter, the questionnaire, and the pre-paid return envelope. A total of 572 (60 per cent response rate) questionnaires were returned within two weeks of delivery. Findings – Findings from a survey of grocery shoppers suggest that one unique store attribute (e.g. personal interaction) can relate negatively to utilitarian shopping value and positively relate to hedonic shopping value, while others (e.g. physical aspects) may have the opposite valence, or direction to the different dimensions of shopping value. Research limitations/implications – Future studies should also include not only shopping value antecedents, but also consequences such as repatronage intentions and anticipation, satisfaction, loyalty and positive word of mouth. Practical implications – Developing adaptive selling techniques and combinations of store layouts may be useful strategies to overcome the differential effects of store attributes on shopping values. Originality/value – This study shows the differential effects that store attributes can have on shopping value. This research extends previous research, which has focused largely on the main effects of store attributes (i.e. one-dimensional measures of store attributes), by finding support for significant interactions between the two types of shopping value and dimensions of store attributes. [ABSTRACT FROM AUTHOR]

In children with sleep-onset insomnia and delayed dim-light melatonin onset, melatonin treatment not only improves sleep but also health, behavior and parenting stress. The aim of the present study was to see whether the latter effects are dependent on the direct effects on sleep. Data come from 41 children (24 boys, 17 girls; mean age = 9.43 years). They entered melatonin treatment (1-5 mg per day) for three weeks, then discontinued treatment by first taking a half dose for one week, and then stopped completely for another week. Sleep was measured with sleep diaries filled in by parents and with actometers. We found a positive effect of actual sleep duration on health but this disappeared after discontinuing treatment. We also found that melatonin treatment decreased behavior problems, which effect appeared to be stronger for children with an earlier dim-light melatonin onset. These results show that the melatonin effects on health and behavior problems may partly be dependent on sleep. [ABSTRACT FROM AUTHOR]