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351.
When children are in the process of learning their mother tongue, they show frequent use of nonfinite clauses, even though they produce finite clauses at the same time, thereby demonstrating the availability of the functional domain associated with finiteness. In this study the hypothesis was tested that this behavior results from an overuse of the normal elliptical repertoire that has also been observed in agrammatic aphasia. The purpose of this overuse is prevention of computational overload. In support of the hypothesis it was found that children behaved very similar to aphasics and normal adults with respect to the following parameters: (a) distribution of types of ellipsis, (b) elaboration of ellipses, (c) word order, (d) subject omission, (e) frequency of weak subject pronouns, and (f) verb type (eventivity). The results also support the Jackson/Jakobson regression hypothesis, at least at the grammatical level.  相似文献   
352.
    
Objective: The extent to which positive (PA) and negative (NA) affect conjointly impact well-being is not yet well understood. Additionally, research investigating the role of affectivity in maintaining well-being among ethnic and racial minorities is scant. The current research demonstrates how polynomial regression and response surface methodology (PR and RSM) may be used to better understand how PA and NA jointly influence stress and well-being.

Design: In Study 1, 291 African-American undergraduates (Mage = 22.91, SD = 6.91; 67% female) completed measures of affectivity and psychological well-being. In Study 2, a community sample of 117 African-Americans (Mage = 31.87, SD = 13.83; 69% female) completed affectivity measures and a laboratory-based social stressor task to assess links between affectivity and salivary cortisol reactivity.

Main outcome measures: Study 1 included life satisfaction, perceived stress and self-reported depressive symptoms. Study 2 included salivary cortisol reactivity.

Results: Across both studies, PA ascendency (i.e. high PA combined with low NA) was associated with better well-being, while NA ascendancy (i.e. high NA combined with low PA) was associated with poorer outcomes.

Conclusion: PR and RSM may provide new insight into the conjoint influence of PA and NA on health and well-being. We discuss potential implications for affectivity research, including race-related explorations.  相似文献   

353.
    
Red-light running (RLR) among motorcyclists at signalised junctions (SJ) in Malaysia are common. This study investigates factors associated with RLR among motorcyclists at signalised junctions. The observation was conducted in 2016–2017, at 26 signalised junctions nationwide, and was analysed using the mixed-effect logistic regression. Out of the 53,475 observed vehicles, only 3.6% run the red light (by which 99% are motorcycles), and from the 19,232 observed motorcycles, 26.2% among motorcyclists run the red light while 54.1% of them, run the red-light without stopping. Factors associated with a high probability of RLR are male riders who do not wear a helmet, who approach the SJ via lane split, who cross SJ via turning, SJ with no traffic island, and SJ with the presence of vehicles waiting on one or both legs. The random parameters show that the majority (83%) of variation in the outcomes occurs among the riders (at Level 1), which suggest that motorcyclists’ characteristics and riding behaviour are still the main factors in affecting the RLR occurrences and require more in-depth study. While 1.5% of variation occurs among the type of motorcycle by region (at Level 2), it also shows that RLR occurs regardless. Other variations are from the range of median width (3.9% at Level 3) and the speed limit range along major roads (9.5% at Level 4). To reduce RLR among motorcyclists, we are recommending that SJ be equipped with traffic islands, and replace the overhead signal pole with pedestal pole.  相似文献   
354.
    
Organizational ambidexterity has been established as an important antecedent of organizational innovation and performance. Recently, researchers have started to argue that ambidexterity is not only essential at the organizational, but also at the individual level. Thus, to be innovative, individuals need to engage in both explorative and exploitative behaviours. However, questions remain regarding the optimal balance of explorative and exploitative behaviours and how ambidexterity can be operationalized. At the organizational level, most empirical research utilized either the difference between, or the product of, exploration and exploitation. In this article, we criticize these approaches on conceptual and methodological grounds and argue for an alternative operationalization of ambidexterity: polynomial regression and response surface methodology. In two diary studies with daily and weekly data, we demonstrate the advantages of this approach. We discuss implications for ambidexterity research and innovation practice.  相似文献   
355.
    
Heteroscedasticity is a well-known issue in linear regression modeling. When heteroscedasticity is observed, researchers are advised to remedy possible model misspecification of the explanatory part of the model (e.g., considering alternative functional forms and/or omitted variables). The present contribution discusses another source of heteroscedasticity in observational data: Directional model misspecifications in the case of nonnormal variables. Directional misspecification refers to situations where alternative models are equally likely to explain the data-generating process (e.g., xy versus yx). It is shown that the homoscedasticity assumption is likely to be violated in models that erroneously treat true nonnormal predictors as response variables. Recently, Direction Dependence Analysis (DDA) has been proposed as a framework to empirically evaluate the direction of effects in linear models. The present study links the phenomenon of heteroscedasticity with DDA and describes visual diagnostics and nine homoscedasticity tests that can be used to make decisions concerning the direction of effects in linear models. Results of a Monte Carlo simulation that demonstrate the adequacy of the approach are presented. An empirical example is provided, and applicability of the methodology in cases of violated assumptions is discussed.  相似文献   
356.
    
Shannon entropy is being increasingly used in biomedical research as an index of complexity and information content in sequences of symbols, e.g. languages, amino acid sequences, DNA methylation patterns and animal vocalizations. Yet, distributional properties of information entropy as a random variable have seldom been the object of study, leading to researchers mainly using linear models or simulation-based analytical approach to assess differences in information content, when entropy is measured repeatedly in different experimental conditions. Here a method to perform inference on entropy in such conditions is proposed. Building on results coming from studies in the field of Bayesian entropy estimation, a symmetric Dirichlet-multinomial regression model, able to deal efficiently with the issue of mean entropy estimation, is formulated. Through a simulation study the model is shown to outperform linear modeling in a vast range of scenarios and to have promising statistical properties. As a practical example, the method is applied to a data set coming from a real experiment on animal communication.  相似文献   
357.
    
A symptom being studied in the process of analysis can be seen as not unlike the unconscious affect it sprang from. The author presents a case in which a symptom, premature ejaculation, was analogous to the unconscious affect of guilt, which itself seemed to be a premature defensive transformation of a deeper current of anger. Guilt was interpreted as if it were a psychic premature ejaculation, a defensive derailment of anger. Fantasy and dream seemed to be engaged in similar transformations, with a fantasy of “premature incarceration” not unlike the symptom itself in its analogous functioning. Analysis of affect, symptom, fantasy, and dream in complex, integrative analytic process led not only to resolution of the symptom itself, but also to a deeper understanding of the mind's complex functioning in general.  相似文献   
358.
    
In the framework of meta‐analysis, moderator analysis is usually performed only univariately. When several study characteristics are available that may account for treatment effect, standard meta‐regression has difficulties in identifying interactions between them. To overcome this problem, meta‐CART has been proposed: an approach that applies classification and regression trees (CART) to identify interactions, and then subgroup meta‐analysis to test the significance of moderator effects. The previous version of meta‐CART has its shortcomings: when applying CART, the sample sizes of studies are not taken into account, and the effect sizes are dichotomized around the median value. Therefore, this article proposes new meta‐CART extensions, weighting study effect sizes by their accuracy, and using a regression tree to avoid dichotomization. In addition, new pruning rules are proposed. The performance of all versions of meta‐CART was evaluated via a Monte Carlo simulation study. The simulation results revealed that meta‐regression trees with random‐effects weights and a 0.5‐standard‐error pruning rule perform best. The required sample size for meta‐CART to achieve satisfactory performance depends on the number of study characteristics, the magnitude of the interactions, and the residual heterogeneity.  相似文献   
359.
    
Despite the fact that data and theories in the social, behavioural, and health sciences are often represented on an ordinal scale, there has been relatively little emphasis on modelling ordinal properties. The most common analytic framework used in psychological science is the general linear model, whose variants include ANOVA, MANOVA, and ordinary linear regression. While these methods are designed to provide the best fit to the metric properties of the data, they are not designed to maximally model ordinal properties. In this paper, we develop an order‐constrained linear least‐squares (OCLO) optimization algorithm that maximizes the linear least‐squares fit to the data conditional on maximizing the ordinal fit based on Kendall's τ. The algorithm builds on the maximum rank correlation estimator (Han, 1987, Journal of Econometrics, 35, 303) and the general monotone model (Dougherty & Thomas, 2012, Psychological Review, 119, 321). Analyses of simulated data indicate that when modelling data that adhere to the assumptions of ordinary least squares, OCLO shows minimal bias, little increase in variance, and almost no loss in out‐of‐sample predictive accuracy. In contrast, under conditions in which data include a small number of extreme scores (fat‐tailed distributions), OCLO shows less bias and variance, and substantially better out‐of‐sample predictive accuracy, even when the outliers are removed. We show that the advantages of OCLO over ordinary least squares in predicting new observations hold across a variety of scenarios in which researchers must decide to retain or eliminate extreme scores when fitting data.  相似文献   
360.
    
Pedestrian crossing treatments, such as Pedestrian Hybrid Beacons (PHBs) and Rectangular Rapid-Flashing Beacons (RRFBs), are traffic control devices implemented to help pedestrians safely cross busy or higher-speed roadways at midblock crossings and uncontrolled intersections. This study aims to assess the effectiveness of the PHB and RRFB by analyzing drivers’ speeding behavior under different roadway types with real-life traffic conditions. In order to understand the effect of pedestrian crossing treatments (i.e., PHB and RRFB) have on drivers’ speeding behavior, this paper analyzes four zones (i.e., one upstream zone and three consecutive downstream zones). For the four analysis zones, different indexes were computed which corresponds to the differences in drivers’ speed when encountered with the pedestrian crossing treatments. A grouped random effect hurdle beta regression model is estimated for the indexes, with a fixed effect hurdle beta model used for comparison and validating the importance of considering the grouped random heterogeneity across participants. The proposed analysis framework was validated by the means of an empirical driving simulator study, based on two urban roads in the Central Florida region, North Alafaya Trail (SR-434) and South Orange Blossom Trail (US-441). The results revealed that the proposed modeling framework reflects drivers’ difference in speed for the different pedestrian crossing treatments. The results suggest that with proper understanding of the PHB, the PHB can reduce drivers speed even beyond the location of the PHB. Meanwhile, the RRFB does have some effect in speed reduction beyond the location of the RRFB, however many drivers failed to acknowledge the RRFB. It is suggested that when drivers’ have proper education on the use of the PHB to reduce speed safely and for the installation of RRFB be on roads with two or less lanes and a speed limit less than 40 mph. While the main purpose of the pedestrian crossing treatments is to help pedestrians cross safely, speed reduction can be considered a byproduct as revealed in this study.  相似文献   
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