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Relating Affect Variability to Complex Skill Acquisition and Adaptive Performance: The Role of Off-Task Attention
Get PDFIndividuals with high affect variability—fluctuations in emotions—tend to react with greater intensity to emotional events and have a more difficult time adjusting to change (Beal & Ghandour, 2011). Although high affect variability has been linked to heightened reactivity to emotionally charged events and poor adjustment, limited research has examined its relationship with skilled performance. Therefore, the purpose of this lab study was to replicate Richels et al. (2020), which was the first empirical study to show how affect variability, specifically affect spin and pulse, undermines complex task performance, and extend Richels et al. (2020) by (1) examining off-task attention as a key explanatory mechanism and (2) including dimensions of affect flux in a relative importance analysis of affect variability scores. Specifically, using a lab sample of 253 undergraduate students (65% male) learning how to play a complex video game, I examined and compared how spin, pulse, and flux in positive activating, positive deactivating, negative activating, and negative deactivating emotions explained variance in skill acquisition and adaptive performance via self-report scores of off-task attention. Spin refers to within-person variability in pleasantness and arousal. Pulse refers to within-person fluctuations in intensity. Flux refers to within-person fluctuations in a particular emotion dimension. Per Nathans et al. (2012), I first examined the relative importance of the different affect variability scores. Then, discontinuous growth modeling was used to disentangle adaptation from acquisition when examining the effects of affect variability on performance. Results indicated the importance of flux indices and suggest that affect variability research has overlooked these indices. In addition, harmful, incremental effects beyond Big Five personality scores for affect variability were found through two mechanisms: primarily (1) via off-task attention (with respect to negative deactivating flux in particular), as well as (2) through moderating the off-task attention-adaptive performance relationship in the case of spin. More simply put, affect variability was found to be detrimental towards complex task learning. Results are further discussed in comparison to Richels et al. (2020), and in terms of the need for adaptability in today’s increasingly uncertain, dynamic world
Assessing scanning strategies with all-digital phased array weather radars for characterization and detection of microbursts
Get PDFMicrobursts are a rapidly evolving, vertically oriented meteorological phenomena that can be extremely hazardous to aviation, and other human activities, if left undetected. The temporal resolution and vertical sampling of the current operational weather radar network (NEXRAD) is too coarse to properly observe the evolution of microbursts and their precursor signatures. However, a potential polarimetric phased array weather radar (PAR) should be able to improve both temporal resolution and spatial sampling of the atmosphere to provide better observation of rapidly evolving hazards such as microbursts. All-digital PAR technology is extremely flexible as a wide array of scanning techniques are available to use; however, this flexibility is not without trade-offs, and these trade-offs are important for understanding how a potential PAR network would operate.
This thesis will lay out a framework and tool set for the study of microbursts and their precursor signatures with varying PAR scanning strategies. This project is the first of its kind to investigate the question of what trade-offs are associated with different scanning strategies when using a planar, mechanically rotating, all-digital PAR to observe and detect microbursts and their precursor signatures, including dual-polarization variables. The scanning strategies analyzed include a traditional volume coverage pattern (VCP) 212, a true range-height indicator (RHI) scan, and imaging at three different spoiled beamwidths in elevation. VCP 212 represents the current operational capacity for microburst observation and detection. True RHI scanning and imaging are more feasible on a PAR system, and they can provide faster temporal resolution and finer vertical sampling.
The framework and tools developed herein are tested in a proof-of-concept analysis by looking at a single wet microburst producing storm generated within a numerical weather prediction (NWP) simulation. Using this NWP simulation data, scanning strategies are implemented through the use of a radar emulator, RSim. These emulations are then analyzed both qualitatively and quantitatively to compare the size, shape, and intensity observations of different microburst precursor signatures: descending reflectivity columns (DRCs), specific differential phase (KDP) cores, and mid-level convergence. Because of
the use of NWP simulations, error analysis is also performed to characterize the impact of estimation errors. The results of this test case analysis of one wet microburst imply that, when utilizing imaging, there is a limit to the benefits provided by increased temporal resolution. This limit occurs at temporal resolutions equal to 30 s and an imaging spoil factor of 5 degrees. When utilizing any spoil factor larger than 5 degrees , the effects of data degradation become too great for the scanning strategy to overcome, the representativeness of the model environment is degraded, and estimation errors become large. However, these results can only be considered preliminary because the analysis only serves as a proof-of-concept
A Multi-Resolution Ensemble Hybrid 4DEnVar with Variable Ensemble Sizes to Improve Global and Tropical Cyclone Track Numerical Prediction
Get PDFOne challenge associated with ensemble-based data assimilation (DA) is the quantitative estimation of the background error covariances. In the current global operational DA system, a reduced resolution background ensemble is adopted, which restricts the ensemble background error covariance from resolving a wide range of scales. A recent study developed a multi-resolution ensemble four-dimensional ensemble-variational (4DEnVar) method and determined that this approach can provide a nearly comparable analysis and forecast to a single high-resolution ensemble approach with the same ensemble size, while substantially lowering the computational cost. This study further develops the multi-resolution ensemble 4DEnVar approach to allow for a flexible number of low- and high-resolution ensemble members as well as different localization length scales between the high- and low-resolution ensembles. The goal of such development is to determine a more effective way of sampling large and small scales to formulate a method aimed at achieving an effective multiscale DA system.
Utilizing the Finite-Volume Cubed Sphere Global Forecast System (FV3GFS), three 4DEnVar experiments with the same computational costs are compared. The first has an 80-member high-resolution background ensemble with single-scale localization. The second and third utilize the multi-resolution ensemble developments. One has a 170-member multi-resolution background ensemble, including 130 low-resolution and 40 high-resolution members. The other has a 204-member multi-resolution background ensemble with 180 low-resolution and 24 high-resolution members. Both multi-resolution ensemble experiments also utilize scale-aware localization radii. Despite having the same costs, the multi-resolution ensemble method decreases tropical cyclone track errors and improves global forecasts for up to five days in lead time. Diagnostics suggest that the multi-resolution ensemble method demonstrates improvement in analyzing large-scale features. At early lead times, improvements are most apparent in the upper levels in the tropics, while at later lead times, the Southern Hemisphere extratropics demonstrates greater improvement. The reduction of forecast errors in the extratropics at later lead times is partially due to improved analyses of large-scale features in the tropics that shift poleward. With regard to tropical cyclone track errors, the multi-resolution ensemble method can more properly correct the large-scale steering flow, leading to more accurate subsequent track forecasts. Additionally, the multi-resolution ensemble with a greater number of high-resolution members performs better than the multi-resolution ensemble with a greater number of low-resolution members in most metrics, demonstrating the value of both increasing sampling at large scales and retaining substantial information at small scales
Parenthood Premiums and Penalties Among Asian American Workers: Exploring the Income Differences Across Gender, Marriage, and Parenthood
Get PDFThis study uses the Current Population Survey to explore the intersections of gender, marriage, and parenthood on Asian American workers’ labor market outcomes. Asian Americans are unique socioeconomically compared to other racial/ethnic minority groups in the US that have been historically and contemporarily disadvantaged. Previous studies measuring the economic attainments of Asian Americans found that both men and women are nearing income parity with White Americans (Greenman 2010, Kim and Sakamoto 2010). However, this raises the question of whether familial factors (i.e., marriage and parenthood) differentially affect Asian American workers’ yearly income and how this may vary by gender at multiple points of the income distribution. I use OLS and quantile regression models to analyze the intraracial gender differences in income by marriage and parenthood factors. Among Asian American workers, I find that men benefit from both the fatherhood and marriage premium. Still, married fathers and single fathers have comparable income suggesting parenthood drives the overall increase in income rather than marriage. Asian American mothers are not affected by the motherhood penalty and see a slight increase in pay after having children, whereas married mothers show negligible differences in pay relative to single mothers. Further, there are larger pay discrepancies among workers in the upper third of the income distribution for married parents, suggesting there is still a gender pay gap regardless of the variation in marital and parental statuses. These findings imply that gendered and racialized views within the labor market influence the perceptions of Asian American workers and produce diverse economic outcomes
Diego Rivera as a Jewish Root-Seeker: Art, Identity Politics, and the "Downtrodden Masses"
No full textThe Mexican muralist Diego Rivera (1886-1957) was Jewish in his imagination only.
During the 1930s, the artist invented a noble Sephardi lineage dating back to the seventeenth-century philosopher, Uriel Acosta (1585-1640). He subverted the Sephardic “Golden Age” Myth by highlighting the formerly downplayed history of persecution and expulsion. The communist leveraged his imaginary Converso genealogy as a way of identifying with the “downtrodden masses.” His Jewish pride and activism formed a bond between him and the many other Jews in his life. By putting him in contact with Jewish realities, his numerous Jewish “comrades,” friends, and acquaintances provided him with the materials he needed to create a symbolic Jewish identity. During the 1930s, the artist went on a “Jewish press-tour,” boasting his Jewish roots in interviews with the Jewish press in Mexico and the United States. Rivera created a Jewish genealogy in response to factors outside of himself, such as the rise of fascism and the intellectual milieu of the Jewish-left during the interwar period. The social activist made a mental connection between the Jews and the Indigenous people of pre-conquest Mexico who were both persecuted by early-modern Spanish institutions. He expressed his symbolic Jewish ethnicity by including motifs of Jews in the Inquisition in his art. This thesis explores how and why Rivera self-fashioned a Jewish identity
