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THE RIGHT SUPPORT : HOW THE EFFECTS OF HELP VARY BASED ON INDIVIDUAL PERCEPTIONS AND NEEDS
Full text linkThesis (Ph.D.)--Michigan State University. Psychology - Doctor of Philosophy, 2025Workplace help is widely recognized for enhancing employee well-being and performance, yet its potential to yield negative outcomes remains poorly understood due to the lack of a unified theoretical framework, passive views of help recipients, and limited focus on recipients\u2019 key psychological factors. This dissertation addresses these issues by integrating Conservation of Resources (COR) theory and Self-Determination Theory (SDT) to examine how help perceptions influence acceptance and outcomes through basic psychological needs (autonomy, competence, relatedness). Two complementary studies tested this model: Study 1 utilized a scenario-based design with 1,163 undergraduates to assess manipulated help features (proactive vs. reactive, disempowering versus empowering, prosocial versus impression management motives) on help acceptance intentions, while Study 2 employed a 5-week multi-wave survey with 99 full-time employees to explore real-world help dynamics and outcomes (task progress, affect, self-esteem). Findings revealed that disempowering help and helper motives were key predictors of basic psychological needs and had downstream effects on reactions to help. Study 2 highlighted the importance of perceived help quality in predicting workplace well-being, as well as the key role of competence needs and status perceptions in forming reactions to help. These results advance COR and SDT by framing help as a dynamic resource exchange contingent on recipient appraisals, offering a novel framework to unify positive and negative support effects. By clarifying the active role of help recipients\u2019 responses to support, this work provides insights into how and why help may backfire. Practically, this work informs organizational policies and training to optimize help delivery, minimizing resource threats and fostering supportive cultures. Future research should explore nuanced appraisal patterns and relational contexts to refine this model.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
FROM PIXELS TO IDENTITY : VISUAL RECOGNITION AND BIOMETRIC APPLICATIONS
Full text linkThesis (Ph.D.)--Michigan State University. Computer Science - Doctor of Philosophy, 2025Automated visual recognition has undergone a transformative evolution, advancing from handcrafted feature extraction to deep learning-driven systems that now permeate modern security, social, and personal computing platforms. Within this rapidly evolving landscape, face and body recognition have emerged as critical tasks\u2014driven by their non-contact nature, scalability, and growing presence in real-world applications. However, achieving robust and generalizable performance in unconstrained settings continues to pose significant challenges, including image degradation, pose misalignment, limited training data, and the complexities of multimodal recognition.This thesis investigates these challenges through the lens of biometric recognition, leveraging the transformative potential of deep learning and generative artificial intelligence to address both algorithmic and data-centric limitations. It introduces six major contributions. AdaFace proposes an adaptive margin loss that prioritizes learning from high-quality samples, improving performance in low-quality image conditions. CAFace targets video-based recognition with an attention-based feature aggregation framework optimized for temporal redundancy and long-duration sequences. DCFace pioneers synthetic dataset generation using a dual-condition diffusion model, enabling ethical, diverse, and scalable data creation for face recognition. KPRPE introduces a keypoint-aware positional encoding scheme that enhances robustness to misalignment and geometric variation. SapiensID unifies face and full-body recognition via a multi-resolution transformer trained on the large-scale, multimodal WebBody4M dataset.Building upon these advances, the thesis concludes with a contribution aimed at real-world deployment: an efficient unified backbone for human recognition. This architecture introduces Keypoint-based Token Fusion (KP-ToFu) and Keypoint Absolute Position Encoding (KP-APE) to reduce computational cost while preserving spatial fidelity and identity-relevant detail. The result is a model that achieves good performance with significantly lower FLOPs, making unified recognition systems viable for resource-constrained applications.Together, these contributions form a comprehensive exploration of visual recognition in the deep learning era, highlighting how adaptive loss design, synthetic data generation, positional encoding, and architectural innovations can collectively address longstanding challenges. This thesis lays the foundation for the next generation of intelligent biometric systems\u2014systems that are robust and explainable for deployment in complex, real-world environments.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
EXPLORING AND ADDRESSING THE VULNERABILITIES OF MULTIMEDIA SERVICES OVER MOBILE NETWORKS : FROM DEVICES TO INFRASTRUCTURE
Full text linkThesis (Ph.D.)--Michigan State University. Computer Science - Doctor of Philosophy, 2025As mobile systems evolve from traditional telephony network architectures (e.g., 3G) to all-IP-based network architectures (4G, 5G, and beyond), the IP Multimedia Subsystem (IMS) was introduced to provide users with a variety of multimedia services\u2014such as voice calls, video calls, SMS, and emergency communications. However, while it enriches daily communication over cellular networks, it also introduces new security threats to the mobile communication ecosystem.In this dissertation, we systematically investigate the vulnerabilities introduced by architectural shifts in mobile networks, spanning from user devices to network infrastructure: (1) on the device side, we analyze the negative impact of transitioning IMS client implementations from traditional hardware-based solutions (in cellular modems) to software-based applications on mobile phones. Our study reveals that this shift significantly expands the attack surface, enabling adversaries to hijack, spoof, or manipulate signaling and media data across various multimedia services; and (2) on the infrastructure side, we examine privacy leakage issues in voice calls over IMS. Although all voice packets and signaling messages are encrypted, the underlying transmission patterns remain observable, thereby leaking user privacy.There are three key lessons learned from our study. First, current IMS standards lack robust security protections for IMS signaling routing on phones. Thus, the common socket communication allows interprocess communication to the IMS client within the same mobile system. This architectural gap enables malware to easily intercept or forge IMS signaling between the IMS client and the IMS server. It enables attacks that can prevent mobile users from accessing multimedia services across all available radio access networks - including 4G, 5G, and Wi-Fi. It also allows adversaries to spoof SMS messages with arbitrary display names. Second, IMS video sessions lack encryption and integrity protection beyond the IP layer. As a result, even with radio and IP layer protection in place, it cannot safeguard the IMS video data on a compromised mobile device before sending it to the air. This opens the door for adversaries to hijack legitimate video streams. We demonstrate that the attacker can hijack video sessions as covert channels, completely bypassing operator-level monitoring and charging policy. Third, although 5G/4G voice calls are encrypted for security and privacy, we unveil that side-channel vulnerabilities persist. In particular, transmission patterns and signaling metadata can still leak sensitive information about 5G/4G call states. We demonstrate a Cross-domain Identity Linkage (CrossIL) attack that can link user identities to their cellular identities with a success rate of 89% to 98%, highlighting the need for deeper privacy-aware design in encrypted mobile voice services. Building on our findings and lessons learned, we propose innovative countermeasures that not only address the identified security vulnerabilities but also pave the way for enabling more reliable and resilient multimedia services over mobile networks.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
THERMAL STEREOLITHOGRAPHY OF HIGH-PERFORMANCE POLYMER DERIVED CERAMICS
Full text linkThesis (Ph.D.)--Michigan State University. Materials Science and Engineering - Doctor of Philosophy, 2025This dissertation aims to develop a novel thermal stereolithography process for shaping polymer-derived ceramics (PDCs). This method solves issues in UV-based additive manufacturing (AM) for ceramic resin 3D printing where high refractive index (RI) fillers lead to low light penetration and resolution. By adopting a thermal NIR laser for the SLA process and using thermal curing, higher loadings of ceramics with higher RI difference between the particles and the resin can be processed. As a result, resin formulations based on SiC, Si, and Si3N4 precursors can be processed with SLA printing to yield 3D structured green bodies that can undergo subsequent pyrolysis to ceramics. In the first part of the research, an acrylate-based resin composition was proposed for SiC-Composite ceramics thermal SLA. This resin composition is based on passive fillers, which do not change throughout the entire process but contribute to the final ceramic yield. The printed structures are debinded and subject to polymer infiltration pyrolysis (PIP), which densifies and strengthens the printed structures. Using a small amount of preceramic polymer in the resin, a percolated structure was formed between particles during debinding to provide additional support for the porous green part. Various 2 D and 2.5 D structures and lattices composed of SiC-Composite ceramics were fabricated through this process, which has improved mechanical properties (flexural strength and toughness) at low pyrolysis temperatures (800 \uf0b0C). In the second part of the research, a preceramic polymer (PCPs)-based resin was utilized for AM of highly crystalline SiC-Composite ceramics using reaction bonding. Elemental silicon nanoparticles were blended into the resin composition as active fillers. This printing of silicon particle-containing resin is only achievable with the thermal SLA process, as silicon has an extremely high RI of 5.44, compared to a refractive index of the resin of approximately 1.4-1.6. The addition of active fillers eliminates the residual carbon from PCP pyrolysis at elevated temperatures and improves mechanical properties. In-situ Raman spectroscopy was used to characterize the polymer-to-ceramic conversion process for PDCs. This analysis allowed for real-time reaction rates to be measured. The high-temperature polymer reaction kinetics were analyzed with the in-situ setup, and the reaction kinetics were clearly illustrated in this research with complementary ex-situ studies. Finally, highly crystalline SiC-Composite ceramics with overhangs are demonstrated with both lab-scale thermal printers and 3DCeram, Sinto industrial printers. Finite element analysis (FEA) for thermal printing was also conducted to optimize the printing process and maximize the printing resolution.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
EXPERIMENTAL AND MASS BALANCE CONSTRAINTS ON NEAR-SURFACE MARINE IODINE REDOX TRANSFORMATIONS
Full text linkThesis (Ph.D.)--Michigan State University. Earth and Environmental Sciences \u2013 Doctor of Philosophy, 2025The distribution of marine iodine is closely linked to the cycling of oxygen (O2), and its concentration in oxygenated waters has implications for ozone (O3) destruction as part of a paleoredox proxy. While the distribution of iodine\u2019s major redox species, iodide (I-) and iodate (IO3-), in the surface ocean is well-documented, the rates and mechanisms of I- oxidation to IO3- remain less well-understood. Iodate in ocean waters is incorporated and preserved within marine carbonate minerals, tracing past and present redox processes and past oxygenation. Iodide formed by microbial reduction of IO3- in surface waters destroys O3 and has implications for modeling of climatological cycles. Iodate reduction is thought to occur fairly quickly and leads to a disequilibrium in [I-] in surface waters, but in situ I- oxidation to IO3- is thought to be slow and may only occur in \u201chotspots\u201d of large biological influence. Due to these slow reported timescales of I- oxidation, ex situ sources of movement, such as upwelling and water mass mixing may have a larger impact on iodine redox species\u2019 distribution that has been previously thought.To calculate rates of I- oxidation to IO3- and quantitatively constrain their distribution, I used three distinct techniques: 1) incubation experiments using the radiotracer 129I, 2) an iodine mass balance of Pacific basin waters, and 3) an Optimum Multi-parameter Analysis (OMPA) across two field areas, 1) the Bermuda Atlantic Time Series (BATS) in the Sargasso Sea and 2) the Pacific Ocean basin at 152\ub0W from Alaska to the Antarctic Ocean, measuring concentrations of iodine\u2019s major redox species I- and IO3-, as well as some intermediates. Samples were collected as part of monthly BATS cruises in the Atlantic and as part of two GEOTRACES cruises (GP15 and GP17-OCE) across the Pacific basin. In the first study, I tested addition of the reactive oxygen species (ROS) superoxide (O2-) and hydrogen peroxide (H2O2) in their role in iodine redox transformations through shipboard radio tracers incubations under ambient conditions as part of the Bermuda Atlantic Time Series (BATS). Incubation trials evaluated the effects of biology, light, and the presence and absence of ROS on I- oxidation over time and at both euphotic and sub-photic depths. I calculated rates of I- oxidation through use of the radiotracer 129I- (t1/2 ~57 Mya) added to all incubations, quantified through measurement of incubations\u2019 129I/127I ratios of individual iodine species determined using Neptune high-resolution multi-collector ICP-MS (MC-ICP-MS). Rates of I- oxidation were found to be sluggish and under the influence of additionally occurring redox transformations, highlighting limited change in iodine redox chemistry associated with in situ processes. In studies two and three, I measured iodine redox species concentrations in surface and depth profile samples from the GEOTRACES GP15 (2018) and GP17-OCE (2022) cruise transects to complete the first iodine meridional transect of the Pacific Ocean. Together with complimentary tracers (7Be), I performed mass balance calculations quantifying the contributions of iodine species from ex situ sources in the Pacific. In addition, a water mass analysis using GP17-OCE hydrographic data provides insight into the eight water masses present in the South Pacific study region and the physical versus biogeochemical changes that contribute to iodine\u2019s distribution throughout the Pacific basin. Ultimately, my data highlight multiple mechanisms likely responsible for iodine cycling and evolution on a basin scale, with important implications for iodine\u2019s broader use as a paleoredox tracer.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
Everyday Nationalism in Korea and Japan : Outgroup Hostility toward Neighboring Countries
Full text linkThesis (Ph.D.)--Michigan State University. Political Science - Doctor of Philosophy, 2025This dissertation investigates the everyday reproduction of nationalism in digital spaces and its consequences for political behavior in East Asia. Moving beyond elite-centric accounts, I conceptualize nationalism as an emotionally charged, performative, and routinized phenomenon, expressed in mundane acts such as online comments, memes, and symbolic language. Drawing on mixed methods across four empirical chapters and two national contexts\u2014South Korea and Japan\u2014I examine how exclusionary nationalist sentiments are articulated, sustained, and politicized in the age of ambient digital communication.For South Korea, I analyze nationally representative survey data to uncover how national pride interacts with political ideology to shape divergent patterns of political participation. While conservatives are more likely to participate when they feel proud of their nation, liberals engage more when national pride is low, reflecting contrasting motivational logic. The next chapter draws on large-scale text data from a major online community during the 2022 World Cup. The analysis shows that national solidarity often coexists with outgroup hostility\u2014particularly toward Japan, Korea\u2019s primary national rival\u2014and that such emotional expressions reinforce national belonging. The third chapter uses a survey experiment to test the causal impact of everyday nationalism. Participants primed with ingroup pride or outgroup hostility showed mixed responses, but routinely digital exposure to nationalist discourse correlated with stronger militaristic and ingroup-oriented preferences. The final chapter turns to Japan, where qualitative analysis of anonymous online commentary reveals that nationalism is frequently performed through collective derogation of Koreans, especially Zainichi Koreans. These expressions reinforce a sense of superiority and unity, but accompanying survey data yields limited evidence that such sentiments translate into political mobilization, underscoring a gap between identity expression and civic action.Together, these findings demonstrate that everyday nationalism is not a dormant ideology but an active emotional practice that shapes political attitudes and behavior in asymmetric ways. The dissertation contributes to bridging nationalism studies and political behavior by illuminating the contingent and affective dimensions of national identity in digitally mediated societies.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
Wireless Communication and Sensing System Design : A Learning-based Approach
Full text linkThesis (Ph.D.)--Michigan State University. Computer Science - Doctor of Philosophy, 2025With the rapid advancement of digital technologies, wireless communication and sensing systems have become increasingly integral to our daily lives. These systems utilize wireless signals not only as data carriers but also as a medium for radio sensing. Model-based approaches have traditionally been a popular choice for addressing existing challenges in communication and sensing. However, model-based approaches struggle to accurately characterize signal propagation, especially at higher frequencies, and optimizing them for communication is even more difficult. Moreover, extracting human motion-related information from these complex signals is often challenging with conventional methods. Recent progress in artificial intelligence (AI) has opened new avenues for addressing these challenges. This thesis explores learning-based approaches to uncover the hidden information embedded within wireless signals. By doing so, it aims to enhance the efficiency of wireless communication systems and enable fine-grained human motion sensing, thereby pushing the boundaries of wireless systems.The first part of this thesis explores the capability of various RF signals to sense different levels of human motion using learning-based approaches. We begin by proposing AuthIoT, a gesture-based wireless authentication scheme designed for IoT devices. AuthIoT leverages a convolutional neural network (CNN) to learn human gesture features from Wi-Fi channel state information (CSI) and maps them to specific letters for device authentication. To enhance robustness and enable gesture recognition across diverse environments, the system employs a feature fusion approach that integrates location-independent features, ensuring strong transferability. Next, we shift our focus to tiny motions and propose RadSee, a system capable of recognizing fine-grained handwriting. We develop a 6 GHz FMCW radar system along with a tailored deep neural network to identify handwritten letters through walls. The model combines a bidirectional long short-term memory (BiLSTM) network with an attention mechanism to leverage temporal dependencies and capture critical features\u2014such as turning points\u2014in radar phase sequences for accurate recognition. We push the limits of this system further with a novel learning framework and introduce RadEye, a system designed to recognize eye movements. Given the subtle nature of eye motion and the challenge of detecting it in RF signals, we adopt a transformer encoder as the feature extractor to more effectively exploit temporal dependencies in the phase sequences. To further enhance performance, we incorporate a state-of-the-art vision-based method to provide guidance and prior knowledge during the learning process. The second part of this thesis focuses on leveraging learning-based solutions to improve the efficiency of wireless communication systems, with particular emphasis on enhancing the throughput of mmWave communication systems. We begin by proposing an uplink multi-user MIMO (MU-MIMO) mmWave communication (UMMC) scheme for WLANs. MU-MIMO techniques are well-known for increasing network efficiency and throughput. A key innovation in this work is a learning-based Bayesian optimization (BayOpt) framework for joint beam search across multiple antennas. This approach eliminates the need for complex channel modeling and identifies optimal beamforming directions with only a few search iterations, significantly reducing beamforming overhead. We then further explore the beamforming problem in mmWave communications, shifting our focus to mobile mmWave networks. In such dynamic environments, beamforming overhead becomes more pronounced. To address this challenge, we leverage the temporal correlation of wireless channels to aid in beam selection. Specifically, we propose a Temporal Beam Prediction (TBP) scheme that enables a mobile mmWave device to predict its future beam direction based on its historical beam selection profile. At the core of this scheme is a modified LSTM architecture, complemented by an adversarial learning model to improve the robustness and generalizability of the beam steering process. This thesis presents efficient communication schemes and novel sensing applications based on learning-driven approaches, paving the way for the design of AI-enabled next-generation wireless communication and sensing systems. It provides detailed descriptions of system implementations, experimental setups, and performance evaluations of the proposed schemes in real-world environments. Furthermore, it offers an in-depth analysis of the limitations of these systems and discusses open challenges in developing future wireless communication and sensing systems using learning-based techniques.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
PHOTIC AND TRANSCRIPTIONAL REGULATION OF THE REPRODUCTIVE AXIS
Full text linkThesis (Ph.D.)--Michigan State University. Neuroscience - Doctor of Philosophy, 2025Shift work is detrimental to many facets of female reproductive health, extending beyond just fertility but also affecting menstrual health, reproductive hormones, and pregnancy. To better understand how the circadian disruption that occurs during shift work impacts reproductive health, we must firstunderstand the regulation of the suprachiasmatic nucleus (SCN) of the hypothalamus, which is the pacemaker and synchronizer of circadian rhythms. The goal of this dissertation is to determine how the regulation of the SCN by homeodomain transcription factors or mistimed light exposure impacts circadian rhythms, female fertility, and estrous cycles in a mouse model. First, we explored the post-developmental roles of the homeodomain transcription factors SIX3 and SIX6 within neuromedin-S\u2013expressing neurons of the SCN. Conditional deletion of Six6 had no measurable effect on circadian or reproductive function, while deletion of Six3 resulted in shortened circadian behavioral rhythms and impaired sperm motility, suggesting distinct and non-redundant roles for these transcription factors in maintaining adult SCN function and reproductive output. Building on the importance of transcriptional regulation in SCN neurons, we next investigated the role of the SCN-enriched transcription factor VAX1 in Vasoactive Intestinal Peptide (VIP)-expressing neurons, which are critical for synchronizing circadian output to downstream systems. Female mice lacking Vax1 in SCN VIP neurons exhibited weakened SCN rhythms, disrupted estrous cyclicity, reduced estrogen, and increased depressive-like behavior. Finally, to model an environmental form of circadian disruption, we used a rotating light (RL) paradigm that mimics human shift work. While some mice maintained regular cycles (RL-C), others became acyclic (RL-A), despite identical light exposure. Compared to control lighting and RL-C mice, RL-A mice had a reduction in circulating progesterone, a blunted luteinizing hormone response to exogenous gonadotropin releasing hormone, and fewer maturing follicles in the ovary. Interestingly, while both RL-C and RL-A groups had comparable conception rates to controls, exposure to RL resulted in reduced litter sizes, suggesting gestational risks independent of estrous cyclicity. Together, these findings provide insight into how circadian disruption, whether genetic or light-induced, may contribute to irregular reproductive cycles, hormone imbalance, and poor reproductive outcomes in women.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
THE IMPACT OF AVIARY DESIGN ON MEASURES OF PRODUCTION, MORTALITY, AND FEAR IN CAGE-FREE LAYING HENS
No full textThesis (M.S.)--Michigan State University. Animal Science - Master of Science, 2025As the laying hen industry transitions to cage-free systems such as aviaries, balancing profitable and efficient egg production with improved hen welfare will ensure long-term industry sustainability. To evaluate the impact of housing system design on egg production and quality, mortality, floor laying, feed delivery, body weight, and fearfulness of the hens, a study was conducted using two different styles of commercial aviaries. At 16 weeks of age (WOA), floor-reared Hy-Line Brown pullets were moved into 7 aviary rooms (N60 = 4 rooms; STEP = 3 rooms). Each room was divided into 4 sections that served as experimental units for most data collection (N60 = 144 birds/section; STEP = 164 birds/section). Mortality, production, and feed delivery data were collected daily across relevant weeks, while egg quality procedures, body weight collection, and fear tests were conducted at specific timepoints throughout the flock cycle. Hen-day production was higher in STEP than N60 (P < 0.05). Mislaid eggs were higher in N60 than STEP across the duration of the study (+5.59\ub10.26%, P < 0.01). Egg quality parameters followed expected age-related changes, with no differences between aviary types. Feed delivery was higher in STEP than N60 (P < 0.01), but body weights were similar between systems. Older hens vocalized less and struggled more in the manual restraint test (P < 0.05), but there were no differences seen in an emergence test. All hens showed increased fear towards humans after the first timepoint when tested in an arena setting (P < 0.01); in the home pen, only N60 hens had a larger human avoidance distance at later timepoints (P < 0.05). Overall, aviary design impacted flock production, the incidence of floor laying, feed delivery, and hen mortality, potentially due to resource availability and use within the system. Fear tests did not reveal major differences in hens living in the two aviary types, but design may affect outcomes when performing testing in the home environment.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references
Essays on agricultural policies, production, and conservation practice adoption
Full text linkThesis (Ph.D.)--Michigan State University. Agricultural, Food and Resource Economics - Doctor of Philosophy, 2025This dissertation consists of four chapters that explore the impacts of agricultural policies on production decisions and the adoption of conservation practices. The first chapter provides an overview and introduction to the dissertation. The second chapter investigates the effect of ethanol production on conservation practice adoption. The third chapter delves into moral hazard behavior in water use. The fourth chapter analyzes the effect of crop insurance premium subsidies on enrollment in wetland easement programs. This dissertation aims to provide empirical evidence on the interplay between production-related policies and their impacts on environmental stewardship, offering insights for policy evaluation and decision-making. The first essay (Chapter 2) examines the effect of ethanol production on the adoption of on-farm conservation practices. From 2002-2019, United States ethanol production increased ten-fold. Using Renewable Fuel Standard (RFS) mandate changes to instrument for ethanol capacity, we assess whether changes in ethanol production affect the prevalence of cover cropping in corn-soy agriculture. We find that a 100 million gallon/year increase in local ethanol capacity implies a 0.35 percentage point decline in cover cropping. Considering a counterfactual where United States ethanol capacity remained at 2005 levels, our estimates imply that United States annual cover cropped area in 2015 would be 570.5 thousand acres greater, leading to additional greenhouse gas sequestration valued at $19.0 million/year based on current estimates of the social cost of carbon.The second essay investigates the effect of crop insurance on water use. Using crop-specific water use data and unit pumping costs for groundwater extraction, we analyze moral hazard behavior in water use and the effect of pumping costs on water use responses to insurance participation. To address the potential endogeneity between water use and insurance participation, we adopt an instrumental variable approach using government-set premium subsidy levels and insurance participation from the previous year. We focus on areas overlying the High Plains Aquifer where groundwater serves as the primary source for irrigation. We find that an increase in insurance participation raises per-acre water use when pumping costs are low. When the pumping costs are high enough, we observe moral hazard behavior in water use, where per-acre water use decreases in response to insurance coverage. For average pumping costs, a one percentage point increase in insurance participation leads to a 0.4% decrease in per-acre water use. These findings provide policy implications for both crop insurance and water regulations. Moral hazard behavior in water use may lead to higher indemnity payouts, whose costs are partially born by taxpayers. In addition, programs increasing water prices may lead to over-pricing and inefficient use of resources, if the moral hazard effect is not considered.The third essay examines whether federal crop insurance premium subsidies discourage enrollment in wetland easement programs. Wetland conservation programs in the United States aim to restore environmentally critical lands that are often at risk of conversion for agricultural use. Using county-level panel data from the Mississippi River Basin between 1997 and 2020, we estimate a Poisson quasi-maximum likelihood model with a control function approach to address endogeneity. Our findings show that a 1% increase in premium subsidy reduces easement enrollment by approximately 3.2%. The economic magnitude of the effect is relatively modest where the average partial effect is estimated to correspond to a reduction of 2.7 enrolled acres. These results suggest that while crop insurance subsidies create some crowding-out effects, their practical impact on long-term wetland conservation commitments remains limited.Description based on online resource. Title from PDF t.p. (Michigan State University Fedora Repository, viewed ).Includes bibliographical references