Browsing by Author "Clegg, Benjamin, committee member"

Now showing 1 - 13 of 13

Open Access
A computational model and empirical study of the self-undermining proposition in job demands-resources theory
(Colorado State University. Libraries, 2019) Walters, Kevin M., author; Fisher, Gwen, advisor; Gibbons, Alyssa, advisor; Clegg, Benjamin, committee member; Conroy, Samantha, committee member; Kraiger, Kurt, committee member
The current conceptual model in job demands-resources (JD-R) theory contains eight propositions to explain the dual processes through which job demands and resources influence individuals' strain, motivation, and job performance. Although the theory is generally well-supported and widely-used in industrial-organizational (I-O) and occupational health (OHP) psychology literature, more research is needed to validate its two most recent propositions; that motivation and strain can lead to increases in job resources and demands through job crafting and self-undermining behaviors, respectively. The goal of this study was to test the dynamic variable relationships in the self-undermining proposition through two research methods in an academic context. First, I developed and tested a computational model of the self-undermining proposition based in JD-R theory and other psychological theories and research. Second, I collected longitudinal data from undergraduate students at two U.S. universities and analyzed the data through cross-lagged panel analyses and repeated measures multivariate analyses of variance. The results of the two methods were contradictory. Specifically, the specifications and theoretical assumptions of the computational model resulted in simulations of a perpetual loss spiral via a positive feedback loop, whereas statistical analyses of the longitudinal data did not identify or support the self-undermining proposition. Overall, the results did not support the self-undermining proposition and were influenced by several methodological limitations of this study, but these limitations and results exemplified several broader limitations of JD-R theory and suggested that the theory is currently inviable and in need of respecification.
Open Access
An evaluation of the collection characteristics and usability factors of three nanoparticle samplers
(Colorado State University. Libraries, 2017) Castano, Andrew, author; Tsai, Candace Su-Jung, advisor; Brazile, William, committee member; Clegg, Benjamin, committee member
Occupational exposure to nanoparticles is a concern to occupational hygienists because of the potential health effects of exposure, the lack of standardized sampling methods and regulatory guidance for exposure limits. Exposure assessments for nanoparticles should include analysis of particles with an electron microscope to allow for identification of particle size, shape and composition. This study is the first to use multiple aerosols to compare the particle size fractions collected by three handheld nanoparticle samplers designed to use transmission electron microscope grids for particle collection. These include the Tsai diffusion sampler (TDS), electrostatic precipitator (ESP), and thermophoretic personal sampler (TPS). Aerosols of sodium chloride, ISO fine test dust, and aluminum oxide were tested and the particle size fractions collected by the nanoparticle samplers were compared. The TDS collected more particles in a wider size range for the lowest concentration aerosol. The ESP sampled for much shorter than the others but collected the most particles for two out of three aerosols. The usability questionnaire assessed all steps involved in sampler usage and rated the features of each device. The TDS and TPS were best suited for full shift sampling and the ESP best for short term. The TDS was the most affordable and has the potential to collect larger particles on a secondary filter. Overall, the TPS was the easiest device to use. Study results indicated that all samplers successfully collected three types of aerosols, with smaller differences in the size fractions they collected and larger differences in the number of particles per surface area of their collection media.
Open Access
Configural asymmetries: an effect of context and object based processes
(Colorado State University. Libraries, 2010) Edler, Joshua R., author; Monnier, Patrick, advisor; Draper, Bruce, committee member; Clegg, Benjamin, committee member
Configural asymmetries refer to differences in visual search performance in which displays composed of objects requiring left/right judgments, are slower to process and incur more errors than displays composed of objects requiring up/down judgments. Two accounts of the effect have emerged in the literature. The Object Region Account, an object-based explanation, posits configural asymmetries are driven by differences in processing the up/down versus left/right regions of an individual object, with left/right regions being less finely processed. The Inter-item Symmetry account, a context-based explanation, posits configural asymmetries are due to mirror symmetry relationships shared between multiple elements in the search display. Specifically, objects sharing vertical mirror symmetry are perceived as more similar and therefore harder to process than objects sharing horizontal mirror symmetry. This study attempted to test and separate these two accounts. Measurements demonstrated that mirror symmetry relationships alone between target and distractors indeed produced an asymmetry in search performance--horizontal mirror symmetry was easier to search through than vertical mirror symmetry. Albeit the magnitude of the effect produced solely by mirror symmetry was noticeably smaller than the effect obtained when objects required left/right versus up/down comparisons (e.g., Monnier, Atarha, Edler, & Birks, 2010; Van Zoest, Giesbrecht, Enns, Kingstone, 2006). Furthermore, when mirror symmetry was held between distractors the reverse effect was found - vertical mirror symmetry was easier to search through than horizontal mirror symmetry. These measurements support configural asymmetries are best understood as an interaction of both object-based and context-based processes and provide support that mirror symmetry is a dimension by which the visual system groups objects.
Open Access
EgoRoom: egocentric 3D pose estimation through multi-coordinates heatmaps
(Colorado State University. Libraries, 2022) Jung, Changsoo, author; Blanchard, Nathaniel, advisor; Beveridge, Ross, committee member; Clegg, Benjamin, committee member
Recent head-mounted virtual reality (VR) devices include fisheye lenses oriented to users' bodies, which enable full body pose estimation from video. However, traditional joint detection methods fail under this use case because fisheye lenses make joint depth information ambiguous, causing body parts to be self-occluded by the distorted torso. To resolve these problems, we propose a novel architecture, EgoRoom, that uses three different types of heatmaps in 3D to predict body joints, even if they are self-occluded. Our approach consists of three main modules. The first module transmutes the fisheye image into feature embeddings via an attention mechanism. Then, the second module utilizes three decoder branches to convert those features into a 3D coordinate system, with each branch corresponding to the xy, yz, and xz planes. Finally, the third module combines the three decoder heatmaps into the predicted 3D pose. Our method achieves state-of-the-art results on the xR-EgoPose dataset.
Open Access
Evaluating factors that impact situation awareness and takeover responses during cyberattacks on connected and automated vehicles
(Colorado State University. Libraries, 2022) Aliebrahimi, Somayeh, author; Miller, Erika, advisor; Bradley, Thomas, committee member; Batchelor, Ann, committee member; Clegg, Benjamin, committee member
Autonomous vehicles offer many potential benefits; however, this expansion of cyber-physical systems into transportation also introduces a new potential vulnerability in terms of cybersecurity threats. It is therefore important to understand the role vehicle occupants can play in preventing and responding to cyberattacks. The objectives of this study are to (1) evaluate how drivers respond to unexpected cyberattacks on automated vehicles, (2) evaluate how cybersecurity knowledge affects situation awareness (SA) during cyberattacks on automated driving, and (3) evaluate how the type of cyberattack affects a drivers' response. A driving simulator study with 20 participants was conducted to measure drivers' performance during unexpected cyberattacks on a SAE Level 2 partially-autonomous vehicle and the infrastructure in the driving environment. The scenarios were developed specifically for use in this study. Each participant experienced four driving scenarios, each scenario with a different cyberattack. Two cyberattacks were directly on the vehicle and two were on the infrastructure. Situation Awareness Global Assessment Technique (SAGAT) was used to measure participants' situation awareness during the drives and at the time of the cyberattacks. Participant takeover responses to the cyberattacks were collected through the driving simulator. Participants also completed a cybersecurity knowledge survey at the end of the experiment to assess their previous overall cyber awareness and experience with autonomous vehicles. Most of the participants noticed the cyberattacks, however only about half of the participants chose to take over control of the vehicle during the attacks, and in one attack no one overtook the automation. Results from ANOVAs showed significantly higher SA for participants with greater familiarity with cybersecurity terms and vehicle-to-everything technology. In addition, SA scores were significantly higher for participants who believed security systems (i.e., firewall, encryption) are important and for those who felt protected against cybercrimes. The present results suggest that increased cybersecurity knowledge can cause a high level of situation awareness during automated driving, which can help drivers to control unexpected driving situations due to cybersecurity attacks. Additionally, the results show that drivers are more likely to takeover control of their automated vehicle for cyberattacks that have known adverse outcomes, such as failing to stop at a stop sign or traffic signal or when their vision is obscured.
Open Access
Exploring correspondences between Gibsonian and telic affordances for object grasping using 3D geometry
(Colorado State University. Libraries, 2023) Tomar, Aniket, author; Krishnaswamy, Nikhil, advisor; Blanchard, Nathaniel, committee member; Clegg, Benjamin, committee member
Object affordance understanding is an important open problem in AI and robotics. Gibsonian affordances of an object are actions afforded due to its physical structure and can be directly perceived by agents. A telic affordance is an action that is conventionalized due to an object's typical use or purpose. This work explores the extent to which a 3D CNN analogue can infer grasp affordances from only 3D shape information. This experiment was designed as a grasp classification task for 3D meshes of common kitchen objects with labels derived from human annotations. 3D shape information was found to be insufficient for current models to learn telic affordances, even though they are successful at shape classification and Gibsonian affordance learning. This was investigated further by training a classifier to predict the telic grasps directly from the human annotations to a higher accuracy indicating that the information required for successful classification existed in the dataset but was not effectively utilized. Finally, the embedding spaces of the two classifiers were compared and found to have no significant correspondence between them. This work hypothesizes that this is due to the two models capturing fundamentally different distributions of affordances with respect to objects, one representing Gibsonian affordances or shape information, and the other, telic affordances
Open Access
Forgetting versus facilitation: the fate of nontested information in the testing effect
(Colorado State University. Libraries, 2015) Bates, Lauren Elizabeth, author; DeLosh, Edward, advisor; Clegg, Benjamin, committee member; Robinson, Daniel, committee member
The testing effect is an established memory phenomenon that demonstrates that retrieval enhances memory relative to restudying. Testing effects can be both direct and indirect. One example of an indirect effect of testing is retrieval-induced forgetting (RIFO), in which taking a test on a subset of information can actually impair recall of related, but nontested information. Recent research has also demonstrated retrieval-induced facilitation (RIFA), the opposite pattern, in which testing on a subset of information enhances memory for related but non-tested information. The present study sought to determine the key factors that determine whether the indirect testing effects on nontested information takes the form of forgetting versus facilitation. Both experiments examined memory for cue-target pairs and vary whether the final test is a cued recall test or a free recall test. Experiment 1 did so for category-exemplar pairs, in which each category cue was paired with several category exemplars, and varied the retention interval as well. Experiment 2 used a construction in which cue words were paired with multiple, unrelated targets. While the results of Experiment 1 supported the hypothesis that a free recall final test would elicit a facilitative indirect testing effect and a cued recall final test would elicit a forgetting effect, Experiment 2 did not follow this pattern. While we are able to draw some conclusions about how certain parameters (e.g. final test type) can aid the presence of either effect, additional avenues should be pursued.
Open Access
Metacognition in the own-race bias: Influences on restudy selection
(Colorado State University. Libraries, 2015) DeLozier, Sarah, author; Rhodes, Matthew G., advisor; Clegg, Benjamin, committee member; Troup, Lucy, committee member; Martey, Rosa, committee member
The own-race bias (ORB), refers to the finding that learners demonstrate poorer memory for faces of other races or ethnicities, compared to those of their own. This memory bias has been examined from an encoding perspective, yet little has been done to examine the possible contribution of metacognition. Under the assumption that monitoring affects control, recognition memory was examined for own-race (White) and other-race (Black) faces. Pilot data suggested that participants might be aware of the ORB, as evinced by their monitoring judgments. The experiment permitted participants to select faces for restudy, make delayed JOLs and restudy selections, then restudy selected faces prior to test. Results demonstrated similar monitoring accuracy for own-race and other-race faces, suggesting that the ORB may not be due to monitoring deficits. Measures of control provided some evidence that learners make similar control judgments for own- and other-race faces, and follow-up experiments are discussed.
Open Access
Mind and world in Kant's Theory of Sensation
(Colorado State University. Libraries, 2015) Murski, Jessica, author; Kneller, Jane, advisor; MacKenzie, Matthew, committee member; Clegg, Benjamin, committee member
In examining sensation as Kant presents it in the Critique of Pure Reason and understanding the problems exemplified in the debate which has arisen surrounding this topic, it becomes clear that Kant believed the objective world to be a product of the mind. This discussion of sensation follows three main themes: (i) the nature of sensation, (ii) the form of sensation and its contribution in determining the spatial properties of objects and (iii) the role of sensation in achieving object-directed cognition. In the first chapter I will present Kant’s view on sensation as it relates to each of these themes. In the second chapter, I will explore the conflict that seems to arise between the nature of sensation and its form and function in the cognitive process. I examine three proposed solutions to this conflict as they are presented by Rolf George, Lorne Falkenstein, and Apaar Kumar. George presents a constructivist account of sensation, while Falkenstein argues that sensations must be physical events in the body of the perceiver. Kumar provides clear evidence from Kant’s writing that Falkenstein’s position is unavailable to Kant and instead proposes a non-constructivist view of sensation. Understanding these concerns helps to highlight a different requirement of sensation in Kant’s cognitive theory. Finally, in the third chapter I provide evidence that Kant took the spatial form of the objective world to be a product of the human mind rather than something that exists “in itself.” This perspective shows why each of the concerns presented in chapter two are important. However, they arise because of the fundamental misunderstanding that Kant took the spatial properties of the external world to exist in its own right, before or aside from human consciousness. I will show how a correct understanding of the relationship between the mind and the external world in Kant’s theory can resolve the conflicts that seem to arise in his theory of sensation.
Open Access
Perception or response bias?: evaluating competing hypotheses through automation of action-control
(Colorado State University. Libraries, 2017) Tenhundfeld, Nathan L., author; Witt, Jessica, advisor; Clegg, Benjamin, committee member; Gibbons, Alyssa, committee member; Smith, Charles A. P., committee member; Wickens, Christopher, committee member
The claim of action-specific researchers is that one's ability to act affects his or her perception of the environment. When using a reach extending tool, such as a stick, objects appear closer than they do without using that stick. However, whether these effects are perception or simply a response bias has been hotly contested. In this dissertation, four experiments were run using the Pong task to be able to differentiate between a response bias and evidence for a perceptual account. Results indicate that not only were results not in line with a response bias account, but they were what the action-specific account of perception would predict. Results are discussed in context of what this means for theories of visual perception. Results are then discussed in relation to the motor simulation hypothesis to evaluate its validity as an explanation for action-specific effects. Finally, given the nature of the experimental design, a framework for a Theory of Automation Embodiment is developed.
Open Access
Something is fishy! - How ambiguous language affects generalization of video action recognition networks
(Colorado State University. Libraries, 2022) Patil, Dhruva Kishor, author; Beveridge, J. Ross, advisor; Krishnaswamy, Nikhil, advisor; Ortega, Francisco R., committee member; Clegg, Benjamin, committee member
Modern neural networks designed for video action recognition are able to classify video snippets with high degrees of confidence and accuracy. The success of these models lies in the complex feature representations they learn from the training data, but the limitations of these models are rarely linked on a deeper level to the inconsistent quality of the training data. Although newer and better approaches pride themselves on higher evaluation metrics, this dissertation questions whether these networks are recognizing the peculiarities of dataset labels. A reason for these peculiarities lies in the deviation from standardized data collection and curation protocols that ensure quality labels. Consequently, the models may learn data properties that are irrelevant or even undesirable when trained using only a forced choice technique. One solution for these shortcomings is to reinspect the training data and gain better insights towards designing more efficient algorithms. The Something-Something dataset, a popular dataset for video action recognition, has large semantic overlaps both visually as well as linguistically between different labels provided for each video sample. It can be argued that there are multiple possible interpretations of actions in videos and the restriction of one label per video can limit or even negatively impact the network's ability to generalize to even the dataset's own testing data. To validate this claim, this dissertation introduces a human-in-the-loop procedure to review the legacy labels and relabel the Something-Something validation data. When the new labels thus obtained are used to reassess the performance of video action recognition networks, significant gains of almost 12% and 3% in the top-1 and top-5 accuracies respectively are reported. This hypothesis is further validated by visualizing the layer-wise internals of the networks using Grad-CAM to show that the model focuses on relevant salient regions when predicting an action in a video.
Open Access
The anteater analysis: a comparison of traveling salesman tour construction methods and their global frequencies
(Colorado State University. Libraries, 2022) Ourada, Shannon A., author; Whitley, Darrell, advisor; Ghosh, Sudipto, committee member; Clegg, Benjamin, committee member
For the Traveling Salesman Problem (TSP), many algorithms have been developed. These include heuristic solvers, such as nearest neighbors and ant colony optimization algorithms. In this work, the ATT48 and EIL101 instances are examined to better understand the difference between biased and unbiased methods of tour construction algorithms when combined with the 2-opt local search operator. First, a sample of tours are constructed. Then, we examine the frequencies of global edges of different sizes using n-grams. Using 2-opt as the tour improvement algorithm, we analyze randomly initialized local optima compared to nearest neighbors local optima as well as ant colony solutions with and without 2-opt. This comparison serves to better understand the nature of these different methods in their relation to the global optimum. We also provide some ways the algorithms may be adapted to take advantage of the global frequencies, particularly the ant colony optimization algorithm.
Open Access
Theoretical analysis of the philosophy and practice of disciplined inquiry
(Colorado State University. Libraries, 2015) Hutchins, Shaun D., author; De Miranda, Michael, advisor; Lynham, Susan, advisor; Wickens, Christopher, committee member; Clegg, Benjamin, committee member
This dissertation theoretically examined the process of disciplined inquiry in the social sciences from its philosophical foundations to its extensions into practice. Key to conceptualization of disciplined inquiry were two regulative ideals: the commitment to the concepts that define the possibility of experience and the commitment to processes for combining the concepts of experience. The paradigm theory of Lincoln, Lynham, and Guba (e.g., Lincoln & Lynham, 2011; Lincoln, Lynham, & Guba, 2011) provided a sophisticated explanation of the possibility of experience that inquirers can commit to when engaging in disciplined inquires. Review of literature revealed an inadequacy in the state of theoretical understanding of processes for combining the concepts of experience. To develop a theoretical agenda of research for disciplined inquiry, the literature on paradigm theory and theory building was analyzed. A historical analysis of paradigm theory revealed milestones in more than 40 years of inquiry focused on conceptualization of the theory. A reverse engineering analysis theoretically examined paradigm theory and its milestones identified from the historical analysis for key features of the theoretical process. A revised conceptualization of disciplined inquiry was presented and a theoretical agenda for developing the underlying theoretical framework for the processes of combining the concepts of experience was outlined.