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911.
This paper presents a simple two-step nonparametric estimator for a triangular simultaneous equation model. Our approach employs series approximations that exploit the additive structure of the model. The first step comprises the nonparametric estimation of the reduced form and the corresponding residuals. The second step is the estimation of the primary equation via nonparametric regression with the reduced form residuals included as a regressor. We derive consistency and asymptotic normality results for our estimator, including optimal convergence rates. Finally we present an empirical example, based on the relationship between the hourly wage rate and annual hours worked, which illustrates the utility of our approach.  相似文献   
912.
Face masks are an effective and important tool to prevent the spread of COVID-19, including among children. However, occluding parts of the face can impact emotion recognition, which is fundamental to effective social interactions. Social distancing, stress, and changes to routines because of the pandemic have also altered the social landscape of children, with implications for social development. To better understand how social input and context impact emotion recognition, the current study investigated emotion recognition in children (7–12 years old, N = 131) using images of both masked and unmasked emotional faces. We also assessed a subsample of participants (“pre-pandemic subsample,” n = 35) who had completed the same emotion recognition task with unmasked faces before and during the pandemic. Masking of faces was related to worse emotion recognition, with more pronounced effects for happy, sad, and fearful faces than angry and neutral faces. Masking was more strongly related to emotion recognition among children whose families reported greater social disruption in response to the pandemic. Finally, in the pre-pandemic subsample, emotion recognition of sad faces was lower during versus before the pandemic relative to other emotions. Together, findings show that occluding face parts and the broader social context (i.e., global pandemic) both impact emotion-relevant judgments in school-aged children.  相似文献   
913.
This longitudinal two-wave cross-national study investigated whether intentions, friends' substance use, and parent-adolescent substance-use specific communication predict adolescent alcohol and cannabis use 1 year later, while estimating reversed links. The temporal order between these two substances was also examined. We used multi-group cross-lagged panel modeling on data from 2 ethnically and socioeconomically diverse samples: Sint Maarten (N = 350; Mage = 14.19) and the Netherlands (N = 602; Mage = 13.50). Results showed that in the Netherlands, cannabis use predicts more subsequent problems (alcohol use, intention to use cannabis, and affiliation with cannabis-using friends). But for Sint Maarten, alcohol use predicts more subsequent problems (cannabis use, intention to use alcohol, and affiliation with alcohol-using friends). These opposing results demonstrate that caution is warranted when generalizing results across countries.  相似文献   
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