Search results

Title: The paradox of asymmetric competition : asymmetric rivalry and asymmetric competitive analysis
Creator: Manjeshwar, Sonia
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "The literature on asymmetric competition has largely portrayed asymmetry to be a competitive advantage. However, this assertion has been made on the basis of studies that assume perfect rationality and ignore cognitive limitations of firms. The salience of assuming cognitive limitations becomes evident when we decompose the concept of asymmetric competition into its individual components of interfirm rivalry and competitive analysis (Chen 1996). At the action level of interfirm rivalry,...
Show more"The literature on asymmetric competition has largely portrayed asymmetry to be a competitive advantage. However, this assertion has been made on the basis of studies that assume perfect rationality and ignore cognitive limitations of firms. The salience of assuming cognitive limitations becomes evident when we decompose the concept of asymmetric competition into its individual components of interfirm rivalry and competitive analysis (Chen 1996). At the action level of interfirm rivalry, asymmetry captures the one-sided, actionresponse dynamic between competing firms, and denotes the competitive advantage of attacking your rivals with impunity. Seen from a focal firm's point of view, asymmetry at the cognitive level of competitive analysis implies a dangerous situation, indicating the firm's inability to recognize or respond to competitive threats from outwardly insignificant competitors (Chen 1996; Desarbo, Grewal, and Wind 2006). The purpose of this study is to develop a theoretical understanding of the paradoxical phenomenon of asymmetric competition and provide insight into why such contradicting outcomes occur. Furthermore, we consider that competitive experience is embedded within the larger context of institutional norms, political systems, and social network structures (Desarbo, Grewal and Wind 2006; Grewal and Dharwadkar 2002). Using data from 41 publicly traded firms in the U.S. retail industry observed over a ten-year period (2003-2012), we examined the paradoxical nature of asymmetric competition. Our results strongly suggest that while strategic adaptations to a context's logic of competition lead to the favorable consequence of asymmetric rivalry, some of the same strategic adaptations lead to the adverse effect of asymmetric competitive analysis. We found that firms' defensive manipulation of political logics in the form of money spent on campaign finance and lobbying is significantly and positively related to the focal firm's ability to carry out greater number of competitive actions relative to rivals. However, defensive manipulation of political logics was also found to be significantly and positively related to the focal firm's market share erosion, indicating impaired awareness that characterizes asymmetric competitive analysis. Similarly, we found that when firms had a hierarchical distribution of positional embeddedness among their key decision-makers, they were able to perform more competitive actions compared to their rivals. However, we also found that a hierarchical distribution of positional embeddedness among key decision-makers to also be positively and significantly related to the firms engaging in a narrow repertoire of competitive actions, indicating exploitative behaviors associated with asymmetric competitive analysis. Our results bear important implications for future research, managerial practices, and public policy, on a topic that has been largely overlooked in the marketing strategy literature."--Pages ii-iii.
Show less

Title: Knowledge, risk, and benefit perceptions : using participatory video and tailored mobile messages to motivate farmers' uptake of drought tolerant (DT) maize seed in kenya
Creator: Cai, Tian (Graduate of Michigan State University)
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "This research documents the design and testing of two strategies for using information and communication technologies (ICTs) to increase farmers' knowledge and uptake of DT maize: (1) locally-made, or 'participatory' video, and (2) a multichannel method that incorporates the same video with timely mobile phone-based audio messages. We conducted a randomized field experiment in Machakos and Makueni counties in Kenya. The experiment randomly allocated the two strategies to farmers in the study...
Show more"This research documents the design and testing of two strategies for using information and communication technologies (ICTs) to increase farmers' knowledge and uptake of DT maize: (1) locally-made, or 'participatory' video, and (2) a multichannel method that incorporates the same video with timely mobile phone-based audio messages. We conducted a randomized field experiment in Machakos and Makueni counties in Kenya. The experiment randomly allocated the two strategies to farmers in the study areas. It was found that, after implementing these interventions, farmers in the multichannel group demonstrated significantly higher knowledge about DT maize and its accompanying management practices. Further, they were significantly more likely to report purchasing improved seed as well as intending to plant DT maize than the farmers in the video-only and the control groups. Farmers in the video-only group did gain a higher level of knowledge than the farmers in the control group; however, this difference is not statistically significant. Moreover, farmers' perceived risk regarding DT maize was found to be associated with their level of knowledge on the varieties and to which kind of treatments they are exposed. Farmers in the two treatment groups showed lower perceived risk than farmers in the control group, especially in the multichannel group. Mitigating the perceived risk of growing the varieties played a crucial role in motivating farmers to test DT maize. We found risk perception was more likely to decrease willingness to test DT maize among farmers who retained lower levels of knowledge than the farmers who had higher levels of knowledge. The results suggest that an ICT strategy integrating multiple ICTs can effectively communicate contextualized knowledge and timely reminders to farmers. This strategy helped farmers gain knowledge about DT maize and induced them to test new seed varieties. This finding contributes to existing theories on the usage of ICTs in agricultural knowledge provision. Previous literature mainly discusses whether single ICTs can improve farmers' knowledge and uptake (e.g. Gandhi, et al., 2009; Cole & Fernando, 2012), while this study investigates how to design ICT-based approaches by integrating various ICTs to make them more effective in innovation diffusion. In this case, those designing ICT strategies should consider farmers' cognitive capacities and the characteristics of agricultural innovations, such as complexity and whether farmers need to practice multiple steps at various points in a growing cycle, as such design can influence farmers' learning and uptake of the innovations. Lastly, this study contributes to a greater understanding of farmers' knowledge and perceptions of DT maize and how they are associated with farmers' uptake decisions."--Pages ii-iii.
Show less

Title: An analysis of content knowledge and cognitive abilities as factors that are associated with algebra performance
Creator: McLean, Tamika Ann
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "The current study investigated college students' content knowledge and cognitive abilities as factors associated with their algebra performance, and examined how combinations of content knowledge and cognitive abilities related to their algebra performance. Specifically, the investigation examined the content knowledge factors of computational fluency, numeracy skills, fraction knowledge, understanding of equivalence, and algebraic reasoning skills, and the cognitive abilities of spatial...
Show more"The current study investigated college students' content knowledge and cognitive abilities as factors associated with their algebra performance, and examined how combinations of content knowledge and cognitive abilities related to their algebra performance. Specifically, the investigation examined the content knowledge factors of computational fluency, numeracy skills, fraction knowledge, understanding of equivalence, and algebraic reasoning skills, and the cognitive abilities of spatial visualization, crystallized intelligence, and fluid intelligence. A multiple regression analysis found that while controlling for gender, the highest math course taken, and the number of years since an algebra course, fraction knowledge and the spatial visualization ability of spatial imagery were statistically significant predictors of algebra performance along with the control variable identifying whether or not participants had taken at least one calculus course. In addition, cluster analysis identified six content knowledge and cognitive ability profiles, with varying levels of both content knowledge and cognitive abilities observed across the six clusters. The six profiles - characterized as Low All, Moderate-Low All, Moderate-High MASMI, Moderate-Low Spatial, Moderate-High All, and High Spatial - varied somewhat in terms of their algebra performance scores. In particular, the participants in the High Spatial cluster group and participants in the Moderate-High All cluster group had similarly high algebra performance scores, which were significantly higher than performances scores observed for participants in the other cluster groups. Additionally, the participants in the other cluster groups exhibited similar low algebra performance scores to each other except for participants in the in the Moderate-Low Spatial and Low All cluster groups. Participants in the Moderate-Low Spatial cluster group had significantly higher algebra performance scores than participants in the Low All cluster group. The differences in algebra performance scores among cluster groups suggested that the observation of higher algebra performance occurred when participants had strong spatial visualization skills, strong fluid intelligence skills, and high content knowledge or when participants had strong fraction knowledge, numeracy skills, algebraic reasoning skills, and spatial imagery skills."--Pages ii-iii.
Show less

Title: Essays on pseudo panel data and treatment effects
Creator: Jia, Fei (College teacher)
Date: 2017
Collection: Electronic Theses & Dissertations
Description: This dissertation is composed of three chapters that study two suitable estimation methods for identifying causal relationships in the presence of (pseudo) panel data. The first and the second chapters are devoted to minimum distance estimation for pseudo panel models, whereas the third chapter is concerned with the estimation of controlled direct effects in causal mediation analyses using panel data.The first chapter focuses on finite sample properties of minimum distance estimators in...
Show moreThis dissertation is composed of three chapters that study two suitable estimation methods for identifying causal relationships in the presence of (pseudo) panel data. The first and the second chapters are devoted to minimum distance estimation for pseudo panel models, whereas the third chapter is concerned with the estimation of controlled direct effects in causal mediation analyses using panel data.The first chapter focuses on finite sample properties of minimum distance estimators in pseudo panel models. Previous research shows theoretically that the minimum distance asymptotic theory is a natural fit for pseudo panel models when cohort sizes are large. However, little is known about how minimum distance estimation performs with a realistic sample size. In a carefully designed simulation study that mimics the sampling scheme of repeated cross sections, we compare the optimal minimum distance estimator to the fixed effects estimator which is identical to the minimum distance estimators using identity weighting matrix. The results show that both estimators perform well in realistic finite sample setups. The results also confirm that the optimal minimum distance estimator is generally more efficient than the fixed effect estimator. In particular, we find that cohort-wise heteroskedasticity and varying cohort size are the two typical scenarios that call for the use of optimal weighting. For the fixed effects estimator, we find that the minimum distance inference is more suitable than the naive inference which incorrectly ignores the estimation errors in the pseudo panel of variable cohort means.The second chapter extends the basic pseudo panel models in the first chapter by adding extra instrumental variables. The additional instruments, if non-redundant, can improve estimation efficiency. To have the efficiency gain result in a general form, we derive it in a non-separable minimum distance framework developed in this chapter. Along with the efficiency gain result, consistency, asymptotic normality, and optimal weighting theorems are also established. This efficiency gain result echoes the property of generalized methods of moments that more moment conditions do not hurt. After developing the results in the non-separable minimum distance framework, we apply them to the extended pseudo panel models. we show that the minimum distance estimators in the extended pseudo panels are generalized least squares estimators, and the optimal weighting matrix is block diagonal. Because of the last fact, the use of optimal weighting becomes more important than in basic pseudo panels. Simulation evidence confirms the theoretical findings in realistic finite sample setups. For an empirical illustration, we apply the method to estimate returns to education using data from the Current Population Survey in the US.The third chapter, coauthored with Zhehui Luo and Alla Sikorskii, proposes a flexible plug-in estimator for controlled direct effects in mediation analyses using the potential outcome framework. A controlled direct effect is the direct treatment effect on an outcome when the indirect treatment effect through a mediator is shut off by holding the mediator fixed. The flexible plug-in estimator for controlled direct effects is a parametric g-formula with an additional partially linear assumption on the outcome equation. Compared to simulation based method in the literature, this estimator avoids estimation of conditional densities and numerical evaluation of expectations. We compare the flexible plug-in estimator to the sequential g-formula estimator, and prove theoretically and via simulation that they are numerically equivalent under certain settings. We also discuss a sensitivity analysis to check the robustness of the flexible plug-in estimator to a particular violation of the sequential ignorability assumption. We illustrate the use of the flexible plug-in estimator in a secondary analysis of a random sample of low birthweight and normal birthweight infants to estimate the controlled direct effect of low birth weight on reading scores at age 17 when a behavior problem index is used as the mediator.
Show less

Title: The role of biodiversity in prairie restoration : tests of theory and implications for management
Creator: Bassett, Tyler Jacob
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "Biodiversity is a primary focus of conservation and restoration, because it has intrinsic value, and because it supports the ecosystem functioning that human well being ultimately depends upon. Theory and experiments support the hypothesis that greater diversity in plant communities supports greater primary productivity, nutrient cycling, invasion resistance and a range of other processes linked to the healthy functioning of ecosystems. However, most of the evidence for diversity-function...
Show more"Biodiversity is a primary focus of conservation and restoration, because it has intrinsic value, and because it supports the ecosystem functioning that human well being ultimately depends upon. Theory and experiments support the hypothesis that greater diversity in plant communities supports greater primary productivity, nutrient cycling, invasion resistance and a range of other processes linked to the healthy functioning of ecosystems. However, most of the evidence for diversity-function relationships is from manipulations of diversity, and a limited number of environmental variables, in small-scale plots. As a result, it is unclear how diversity-function relationships will scale up to dynamic, "real-world" ecosystems, which limits the capacity to effectively manage both biodiversity and ecosystem functioning. I examined diversity-function relationships in prairie restorations, which provide an ideal scenario for bridging the gap between experimental and natural ecosystems because diversity is manipulated at large scales and across complex biotic and abiotic gradients. It is clear from experimental evidence that diversity plays a role in supporting ecosystem functioning. My findings elucidate how important diversity is at the scale of natural ecosystems, relative to both abiotic (e.g., soil properties) and biotic (e.g., dominant species) factors that are likely to covary with diversity at large scales. I also contribute directly to the practice of restoration by working in real restorations, linking variation in management actions, such as seed sowing and prescribed fire, to outcomes of immediate concern to managers, such as the relationship between native and exotic species."--Abstract.
Show less

Title: Social Distance in Iraq and Lebanon
Creator: Mohammed, Jihan A.
Date: 2017
Collection: Electronic Theses & Dissertations
Description: Research has found that tensions, conflicts, and wars worsen the views groups hold towards each other and, plausibly, increase social distance. ... Since the twentieth century the Middle East is caught up in interlocking pattern of crises, conflicts, wars, and terrorism. Almost every country in the region have serious problems in social and political stability. The focus of this study is to investigate levels of social distance in conflict areas like Iraq and Lebanon where thousands of...
Show moreResearch has found that tensions, conflicts, and wars worsen the views groups hold towards each other and, plausibly, increase social distance. ... Since the twentieth century the Middle East is caught up in interlocking pattern of crises, conflicts, wars, and terrorism. Almost every country in the region have serious problems in social and political stability. The focus of this study is to investigate levels of social distance in conflict areas like Iraq and Lebanon where thousands of people have been killed and displaced because of civils wars and counter-terrorism. ... We are specifically interested to see the relative importance of: practicing religious rituals i.e. praying, fasting, attending Friday prayer/Sunday service; sectarian/denominational identification; and voting behavior as determinants of social distance.--Abstract
Show less

Title: "Lost space" and "artialised space" : analyzing photographic representations in Paris
Creator: Hou, Xiao
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "Photographs are ubiquitous, and we seem to understand the world through photographs a lot more. But how does the ubiquitous photographic representation affect our understanding of the urban environment? The main aim of this study was to examine and explore how and why a city is represented in people's photographs differently." -- Abstract.

Title: Cultural elements relative to dietary behaviors for diabetes self-management among Mexican-Americans
Creator: Plasencia, Julie
Date: 2017
Collection: Electronic Theses & Dissertations
Description: Specific aspects of culture relative to Mexican-Americans have not been characterized relative to medical nutrition therapy (MNT) and/or education for in type 2 diabetes mellitus (T2DM) self-management and other health problems. The objective of the study is to add meaningful insight into culturally relevant aspects necessary for the development and/or adaptation of T2DM self-management programming for Mexican-Americans. To accomplish this, aspects of culture relative to T2DM self-management...
Show moreSpecific aspects of culture relative to Mexican-Americans have not been characterized relative to medical nutrition therapy (MNT) and/or education for in type 2 diabetes mellitus (T2DM) self-management and other health problems. The objective of the study is to add meaningful insight into culturally relevant aspects necessary for the development and/or adaptation of T2DM self-management programming for Mexican-Americans. To accomplish this, aspects of culture relative to T2DM self-management are explored through several innovative approaches. First, using a content analysis approach, an in-depth examination of literature on the perceptions of Mexican-Americans on self-management diet and physical activity behaviors was completed to identify cultural elements. Next, perceptions of culture by nutrition experts, specifically targeting registered dietitians, were examined using an online survey that explores cultural elements used in practice when counseling Mexican-American diabetes patients on achievement of self-management goals. Finally, curricula used in T2DM interventions that target Mexican-Americans were examined using a content analysis approach for the extent to which cultural elements are integrated into the written curricula. Results from the first aim identified several surface and deep level cultural elements. The top surface level elements mostly frequently found in the qualitative studies were food habits (n=15/19), food preferences (n=14/19), use or acquisition of nutrition knowledge (11/19) and healthcare provider preferences (11/19). The top three deep level elements most commonly found were general health beliefs or attitudes (n=19/19), beliefs or attitudes about foods in general (n=17/19) and family turmoil (n=14/19). Findings from the second aim demonstrated that Registered Dietitian Nutritionist (RDNs) vary in their perceptions of cultural elements depending on years of professional experience. For example, the least experienced RDNs (average of 4.62 years) were more likely to perceive that beliefs about Mexican and American foods in general important for diabetes self-management compared to the highly experienced group of RDNs (average of 33.98 years). Additionally, RDNs who provided T2DM counseling to Mexican-Americans were more likely to fall in the least experienced group, be Certified Diabetes Educators, work in outpatient settings and provide individual counseling. With regards to cultural competency levels assessed, there were no differences assessed between the three experience levels RDNs were grouped in.The final aim examined how six T2DM intervention curricula incorporated cultural elements. The results of this content analysis showed that the main cultural elements incorporated were related to diet were food habits, food preferences or avoidances, acquisition and use of nutrition knowledge, beliefs about Mexican/cultural foods and general health beliefs about foods. Specific health beliefs and values commonly recognized as influential factors for self-management and healthcare seeking behaviors for Mexican-Americans were less likely to be addressed. However, overcoming barriers, general health beliefs about diabetes and family influences were incorporated in some of the curricula.Through this research, we identified that there is a demand for culture-specific cultural competency trainings among RDNs and that several tools are available to encourage dissemination of evidence-based findings such as integrating background information in diabetes self-management curricula and cultural competency training opportunities (such as professional development and higher education). Overall, these results suggest that culture-specific knowledge is not uniformly evident in nutrition therapy practice when Mexican-Americans who have T2DM. This may also be true for all healthcare professions working with this and other ethnic populations. Therefore, future research should focus on identifying opportunities for culture-specific cultural competency training, how these trainings transfer into better outcomes for patients, and finally, examining which and how cultural elements provide better behavior change outcomes in interventions.
Show less

Title: Whole tree renewal regenerates fruiting structures quickly in mature orchards
Creator: Larson, James Edward
Date: 2017
Collection: Electronic Theses & Dissertations
Description: Renewal of fruiting wood to maintain young reproductive meristems with optimal canopy light interception and distribution is key for high productivity and fruit quality throughout the life of a sweet cherry (Prunus avium L.) orchard. Typical renewal involves replacement of 10 to 20% of the tree canopy annually by removing one to several of the largest branches. In a mature orchard, this renewal process is subject to competition between sun-exposed fruiting sites and interior canopy renewal...
Show moreRenewal of fruiting wood to maintain young reproductive meristems with optimal canopy light interception and distribution is key for high productivity and fruit quality throughout the life of a sweet cherry (Prunus avium L.) orchard. Typical renewal involves replacement of 10 to 20% of the tree canopy annually by removing one to several of the largest branches. In a mature orchard, this renewal process is subject to competition between sun-exposed fruiting sites and interior canopy renewal sites that intercept less light and compete poorly for translocated photoassimilates, often resulting in poor renewal growth. This is particularly problematic for high density orchards that utilize rootstocks selected for reduced vigor and high productivity. Renewal of canopy fruiting sites on a whole tree basis is an alternative renewal method that eliminates the competitive inhibition of shoot regrowth. This study explores the initial response of sweet cherry trees on various training systems and size-controlling rootstocks to whole tree renewal. Four training systems were studied: Tall Spindle Axe, Super Slender Axe, Upright Fruiting Offshoots, and Kym Green Bush. In 2016, whole tree renewal of the four systems was studied with ‘Benton’ cultivar on three rootstocks of varying vigor: Gisela 3, Gisela 5, and Gisela 6. During bloom, all fruit-bearing components of the canopy were pruned back to stubs close to the permanent structure. TSA resulted in the higher number of shoots, while KGB and UFO had the longest average shoot length. The results indicate that each canopy system-rootstock combination refilled canopy space, except for KGB on each rootstock, to quickly regenerate fruiting sites.
Show less

Title: Remains of Khmer Rouge Violence : the Materiality of Bones as Scientific Evidence and Affective Agents of Memory
Creator: Fleischman, Julie Michele
Date: 2017
Collection: Electronic Theses & Dissertations
Description: The Khmer Rouge regime, led by the infamous Pol Pot, governed Cambodia from 1975 to 1979. Living conditions were severe, and it is estimated that approximately one quarter of the Cambodian population of nearly eight million died from mistreatment, overwork, malnutrition, and violence. Using a biocultural anthropological approach, this research addressed questions concerning individuals executed by the Khmer Rouge regime and the agency (the effect on living individuals) of the resulting...
Show moreThe Khmer Rouge regime, led by the infamous Pol Pot, governed Cambodia from 1975 to 1979. Living conditions were severe, and it is estimated that approximately one quarter of the Cambodian population of nearly eight million died from mistreatment, overwork, malnutrition, and violence. Using a biocultural anthropological approach, this research addressed questions concerning individuals executed by the Khmer Rouge regime and the agency (the effect on living individuals) of the resulting skeletal remains.An osteological analysis of more than 500 crania was conducted at the Choeung Ek Genocidal Center (Choeung Ek) in Phnom Penh. More than 100 original Khmer Rouge execution lists from the detention and torture facility known as S-21—today known as the Tuol Sleng Genocide Museum—were assessed to gather known demographic data for those who were executed and buried at Choeung Ek between 1977 and 1979. To comprehend the incorporation of human skeletal remains from the Khmer Rouge period into the socio-religious framework of modern Cambodia, 13 memorial stupa containing human remains were visited and the caretakers of these memorials were interviewed.The 508 crania at Choeung Ek were assessed for demographic characteristics and traumatic injuries. Results indicate that the majority of crania were estimated to be male (82.9%) and nearly all were of Asian ancestry (86%). The majority of the individuals were young adults (68.3%) between the ages of 20 and 35 years old, although juveniles and older adults were represented. Perimortem trauma was present on 311 crania (61%), with 179 (58%) having discernable impact locations. Blunt force injuries (87%) were the most common mechanism of trauma and the basicranium (53%) was the most frequently impacted region. When the mechanism and location of traumatic injuries were evaluated by sex and age-at-death categories, no statistically significant differences were found indicating that all victims with perimortem trauma were subjected to similar execution methods regardless of their age or sex.At the Tuol Sleng Genocide Museum, 97 definitive Khmer Rouge execution lists were evaluated documenting the murders of 6,285 individuals. The majority (82.1%) were male, the minimum age was 11, the maximum age was 77, and the average age was 29.1 years. When these archival demographic data were compared to these osteologial data, however, there were statistically significant differences between the samples.Observational data from all 13 memorials, and interview data from 10 memorials indicated that the human remains were not formally preserved to prevent decay and there was never a clear indication of how many individuals were represented by the remains with the stupa. The informant’s responses addressed issues such as the identification of the human remains within the memorial, current religious practices conducted at the memorials often in conjunction with caring for the remains, how the remains are displayed for knowledge and/or teaching purposes—although often with a political undertone—and that the memory of the Khmer Rouge period, as well as that of the victims is crucial for modern Cambodians.This research embraced a holistic approach to move beyond the confines of traditional osteological laboratory research by addressing the social impact of the remains. While the Khmer Rouge period was devastating, the human remains of the victims have not been forgotten; the remains continue to remind all who visit that immeasurable violence occurred in Cambodia but also that Cambodians are resilient and they will continue to memorialize those they lost.
Show less

Title: Suicide, signals, and symbionts : evolving cooperation in agent-based systems
Creator: Vostinar, Anya E.
Date: 2017
Collection: Electronic Theses & Dissertations
Description: Cooperation is ubiquitous in nature despite the constant pressure for organisms to cheat by receiving a benefit from cooperators, while not cooperating themselves. The continued evolution and persistence of countless forms of cooperation is a central topic in evolutionary theory. Extensive research has been done on the theoretical dynamics of cooperation through game theory and the natural examples of cooperation. However, it remains difficult to understand thoroughly the evolution of many...
Show moreCooperation is ubiquitous in nature despite the constant pressure for organisms to cheat by receiving a benefit from cooperators, while not cooperating themselves. The continued evolution and persistence of countless forms of cooperation is a central topic in evolutionary theory. Extensive research has been done on the theoretical dynamics of cooperation through game theory and the natural examples of cooperation. However, it remains difficult to understand thoroughly the evolution of many cooperative systems, due in part to the ancient origins of these systems and the long time scales required to see cooperation evolve in any natural populations. I have systematically analyzed the evolution of three broad types of cooperation: programmed cell death, quorum sensing, and mutualisms (cooperation across species). I have provided evidence that programmed cell death can originate due to kin selection. I have also created two new systems to enable the extensive exploration of factors that affect the evolution of public goods cooperation and mutualism. Using these systems, I determine the effects of environmental factors on the evolution of public goods cooperation and mutualism. By uniting the expansive theoretical work on these forms of cooperation with a fully-controlled experimental system, I contributed to our understanding of how these forms of cooperation can emerge and be maintained in industrial and medical applications that rely on bacterial cooperation.
Show less

Title: Essays in economic development
Creator: Ivanyna, Maksym
Date: 2017
Collection: Electronic Theses & Dissertations
Description: The dissertation consists of three essays: "Benefits of diversification in agriculture: Evidence from Malawi", "Corruption and economic growth revisited" and "How close is your government to its people? Worldwide indicators on localization and decentralization". All three essays focus on issues, which are particularly important for developing countries: food security, corruption, decentralization.In the first essay I use data from a farmers' survey in Malawi to compare two agricultural...
Show moreThe dissertation consists of three essays: "Benefits of diversification in agriculture: Evidence from Malawi", "Corruption and economic growth revisited" and "How close is your government to its people? Worldwide indicators on localization and decentralization". All three essays focus on issues, which are particularly important for developing countries: food security, corruption, decentralization.In the first essay I use data from a farmers' survey in Malawi to compare two agricultural technologies: monoculture maize and crop diversification (maize-legume intercrop). I match farmers locations with data on rainfall and air temperature to test whether more biodiverse agriculture is better at absorbing weather shocks. The data make it possible to compare variation not only over time, but also over different plots within the same time period, which helps reduce omitted variable bias. The instrumental variable method is used to eliminate rainfall measurement error. For a number of specifications, and controlling for fertilizer use, crop diversification is both more productive than monoculture maize and more resistant to weather shocks. Although I am not able to identify the average population effect, I show that the effect I identify is likely to prevail if the Malawian government decides to shift the focus of its agricultural subsidy at the margin from fertilizer to legume seeds and education.The focus of the second essay is on corruption. While literature finds many channels through which corruption can hurt economic growth, the link proved hard to establish in empirical cross-country studies. In this paper I show that part of the explanation of this puzzle is that there is a reverse causality: everything else equal, exogenously-driven economic growth can increase corruption. The reason is that the boost to output increases tax revenue, and hence pool of resources that corrupt public officials can embezzle. I show the workings of this channel in a simple stylized model, which is then accompanied by numerical simulations in a dynamic general equilibium overlapping-generations model, which allows for corruption and tax evasion. I also present empirical evidence, which supports my findings.The third chapter assembles and analyzes a unique data base on local governance that provides a first approximation of the institutional architecture of local governance that has emerged as a result of the silent revolution (decentralization reforms) of the last three decades on moving governments closer to people. An important feature of this data set is that, for comparative purposes, it measures government decision making at the local level i.e. the order of government that is closest to the people and hence providing a better indicator of decentralized decision making as compared to the "sub-national governments" that also include intermediate tiers of provinces and states, used by the existing literature. This unique data set for 182 countries attempts to capture institutional dimensions of political, fiscal and administrative autonomy enjoyed by local governments under diverse multi-order governance regimes using a common framework. These dimensions are aggregated to develop a "decentralization index" and then adjusted for heterogeneity to develop a "government closeness index" that provides an overall ranking of countries on the closeness of their government to the people.
Show less

Title: The design and synthesis of novel proteasome inhibitors : studies on the synthesis of nagelamide M and analogs, the synthesis of rapamycin based proteasome inhibitors, and the synthesis of TCH based molecular probes for binding site determination
Creator: Giletto, Matthew Basil
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "The two primary physiologic mechanisms for the recycling of amino acids from no-longer needed or damaged proteins are autophagy and enzymatically via the proteasome. Inhibition of the proteasome has emerged as the preeminent means for treating cancers that constitutively overproduce proteins, particularly multiple myeloma. Two drugs currently available for the treatment of multiple myeloma, BortezomibTM and KyprolisTM, inhibit the proteasome by binding to the catalytically active sites...
Show more"The two primary physiologic mechanisms for the recycling of amino acids from no-longer needed or damaged proteins are autophagy and enzymatically via the proteasome. Inhibition of the proteasome has emerged as the preeminent means for treating cancers that constitutively overproduce proteins, particularly multiple myeloma. Two drugs currently available for the treatment of multiple myeloma, BortezomibTM and KyprolisTM, inhibit the proteasome by binding to the catalytically active sites through a competitive mechanism. While initially effective, over time the resistance that is typical of competitive binders emerges, and relapse rates are currently measured at 97 %, with the average survival time after being one year. Additionally the most common side effect is neuropathy, which typically does not abate after discontinuation of chemotherapy. The current state of the art demonstrates the need not only for new proteasome inhibitors, but inhibitors that act through a different mechanism. The Tepe group was the first to develop such a molecule, imidazolines of the TCH-series, which bind to the proteasome via a noncompetitive mechanism. The details of the interaction of these molecules with the proteasome have been extensively studied, but the location of the binding site remains elusive. In this work, several molecular probes were designed and synthesized (two diazirine photoaffinity-TCH hybrids and a biotin-TCH hybrid) to elucidate the location of the binding site. Currently biological testing is underway. Additionally, a library of analogs based on the natural product rapamycin were designed and synthesized. An analog was discovered that was equipotent to the natural product itself, which could be synthesized on a gram scale in three steps from commercially available materials. To discover the binding site of these molecules, a diazirine photoaffinity probe was designed and synthesized. Enough biological data was generated to refine the library and design and synthesize a second generation of the analogs; currently biological testing of these analogs is underway. Lastly, extensive studies on the total synthesis of the pyrrole-imidazole natural product nagelamide M were designed and performed. These studies relied mainly on the use of C-H activation to functionalize a methylene C-H bond adjacent to a heteroatom. None of the key reactions were successful, and the synthesis stalled at an early stage. Overall this thesis describes several advances in the areas of drug discovery and proteasome inhibition, and perhaps most excitingly access to molecules that could elucidate the binding site of the TCH molecules."--Pages ii-iii.
Show less

Title: An individual differences approach to improving low target prevalence visual search performance
Creator: Peltier, Chad
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "Critical real-world visual search tasks such as radiology and baggage screening rely on the detection of rare targets that may only be present on as few as .3% of searches (Gur et al., 2004). When targets are rare, observers search for a shorter amount of time and miss targets more often than when targets are common, a phenomenon known as the low prevalence effect (LPE). Given the real-world importance of the detection of low prevalence targets, researchers have attempted to improve search...
Show more"Critical real-world visual search tasks such as radiology and baggage screening rely on the detection of rare targets that may only be present on as few as .3% of searches (Gur et al., 2004). When targets are rare, observers search for a shorter amount of time and miss targets more often than when targets are common, a phenomenon known as the low prevalence effect (LPE). Given the real-world importance of the detection of low prevalence targets, researchers have attempted to improve search performance. There have been several experimental attempts to reduce the LPE, but none have been wholly successful, as even the best methods have increased hits at the cost of more false alarms. As an alternative to improving visual search performance through experimental manipulations, researchers have recently started using an individual differences approach to predict those who would be best at rare target detection. The individual differences approach has shown that it is possible to predict low prevalence target detection using working memory capacity (WMC) (Peltier & Becker, 2016b; Schwark et al., 2012) and moderate prevalence target detection using a personality assessment (Biggs, Clark, & Mitroff, 2017) and vigilance (Adamo, Cain, & Mitroff, 2016). Experiment 1 expands on the previous research by predicting low prevalence visual search performance using measures of WMC, near transfer high prevalence visual search accuracy, vigilance, attentional control, and introversion. The regression using these predictors accounts for 52% of the variance in accuracy. Experiment 2 addresses practical and theoretical limitations of Experiment 1 by replicating the original finding, including new potential predictors of low prevalence search performance (fluid intelligence, task unrelated thought frequency, and far transfer search accuracy), using more realistic search stimuli to increase external validity, and using eye tracking to investigate how individual differences relate to specific components of performance. The results show that near transfer search, far transfer search, WMC, introversion, and fluid intelligence account for 53% of the variance in accuracy in a more realistic low prevalence search. Using the beta weights from Experiment 1's significant predictors and each observer's score on the corresponding measures in Experiment 2, I find that the old predictors account for 42% of the variance in a novel search task's accuracy. Finally, the eye-tracking results show that we can significantly predict quitting thresholds (the number of items inspected before terminating search), selection error rates (misses caused by never inspecting the target), identification error rates (misses caused by misidentifying an inspected target), item re-inspection rates, target decision times, and distractor decision times. I conclude that the individual differences approach has the potential to be a highly effective tool in selecting those who are most likely to perform at a high level in real-world searches."--Pages ii-iii.
Show less

Title: An agent model of vertical integration in telecommunications and content
Creator: Koning, Kendall Jay
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "This dissertation explores several important telecommunications policy issues in light of recent developments in the wireline broadband and online video markets." -- Abstract.

Title: Webbed space : online feminist discourse in the fourth wave
Creator: Sweo, Naomi
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "This thesis examines the feminist online discourse community 'A Practical Wedding' and identifies four characteristics that make it a model for feminist online interaction: 1. the connection of users' online identities with their real-life selves; 2. the non-hierarchical structure of the community; 3. the productive exchanges between members; and 4. the site- and Internet-wide intertextuality. Technofeminist threads in rhetoric and composition in the late 1990's and early 2000's were mostly...
Show more"This thesis examines the feminist online discourse community 'A Practical Wedding' and identifies four characteristics that make it a model for feminist online interaction: 1. the connection of users' online identities with their real-life selves; 2. the non-hierarchical structure of the community; 3. the productive exchanges between members; and 4. the site- and Internet-wide intertextuality. Technofeminist threads in rhetoric and composition in the late 1990's and early 2000's were mostly abandoned. They deserve renewed attention, with updating based on the existence and necessity of fourth-wave feminism today. The author first describes her own origin story that led to her interest in this research. She then applies a system of virtual critical discourse analysis and resultant coding schema to four representative posts and their comment sections. This thesis concludes with a call for the creation of more communitarian, feminist spaces on the Internet with similar models of engagement to those used in 'A Practical Wedding.'"--Page ii.
Show less

Title: Conceptualizing gender, contextualizing curriculum : a case study of teacher education coursework
Creator: Kean, M. Eli
Date: 2017
Collection: Electronic Theses & Dissertations
Description: This study explores and theorizes around issues of transgender curriculum in teacher education courses. Using a conceptual framework informed by both transgender theory and curriculum theory, I propose a Critical Trans Framework to analyze what trans-related curricular materials are currently used in teacher education courses and what factors influence teacher educators’ curricular choices. Gender-expansive syllabi were identified as those that contained required readings utilizing anti...
Show moreThis study explores and theorizes around issues of transgender curriculum in teacher education courses. Using a conceptual framework informed by both transgender theory and curriculum theory, I propose a Critical Trans Framework to analyze what trans-related curricular materials are currently used in teacher education courses and what factors influence teacher educators’ curricular choices. Gender-expansive syllabi were identified as those that contained required readings utilizing anti-oppressive, humanizing, intersectional, or justice-oriented characteristics. Data sources for this study include course syllabi, surveys with Likert-scale and open-ended questions, one-on-one interviews, and a group interview with all participants. Findings explore how participants were understanding or conceptualizing gender, queer, and heteronormativity in relation to trans. Participants had a somewhat similar approach to teaching gender as a concept, but had divergent and multiple understandings of queer. Heteronormativity was understood to be the overarching system of oppression targeting all non-heterosexual and non-cisgender people. In describing how they teach trans, the participants described attempts to complicate dominant trans narratives, establish class norms that created an environment ripe for gender exploration, and represent trans people through first-person narratives. Influential contextual elements outside the classroom include institutional and/or programmatic supports or constraints, the instructor’s own understanding and experience with transgender issues, and state or local policies.
Show less

Title: Behavioral ecology of Amazonian mixed-species flocks
Creator: Williams, Sean M.
Date: 2017
Collection: Electronic Theses & Dissertations
Description: Amazonian mixed-species flocks of birds are remarkable by virtue of their strength of interspecific association. In these flocks, individuals of different species associate with each other for the duration of their lives, i.e. during all daylight hours, 365 days of the year across many years. These obligate relationships provide a unique opportunity to study the behavioral ecology of dependent interspecific relationships. I break my thesis into three chapters. First, I ask whether the...
Show moreAmazonian mixed-species flocks of birds are remarkable by virtue of their strength of interspecific association. In these flocks, individuals of different species associate with each other for the duration of their lives, i.e. during all daylight hours, 365 days of the year across many years. These obligate relationships provide a unique opportunity to study the behavioral ecology of dependent interspecific relationships. I break my thesis into three chapters. First, I ask whether the relationship between two obligatorily flocking species (nuclear antshrike and antwren species) is symmetrical and whether transient species (non-obligate flocking species) are equally attracted to the nuclear species. Are the transient species equally attracted to the two nuclear species? And are the two nuclear species equally attracted to each other? This first question was necessary to ask before my other questions because I needed to know which species are following other species and which species are being followed. Then, I ask whether the behavior of a single species (the same antshrike species I determined was mostly being followed in the first question) can predict the space use of the whole flock and what environmental and behavioral variables explain the space use. Finally, I ask whether a particular context-dependent vocalization of the antshrike might serve as a mechanism of interspecific cohesion of the flock. After having spent hundreds of hours studying the space use of flocks in order to define the spatial distribution of flocks within their territories, this last question followed naturally since the mechanism of interspecific cohesion was central to the coordination of the movement of the flock through space. In resident Amazonian mixed-species flocks, the pattern of attraction of transient species to nuclear antshrikes and antwrens, and the pattern of heterospecific attraction between the nuclear species, are undocumented. Patterns of attraction can help elucidate the nature of interspecific relationships, i.e. whether they are mutualistic, commensal, or parasitic. We played antshrike and antwren vocalizations to flocks and observed how many transient species approached the playbacks, whether antshrikes and antwrens were attracted to each others' playbacks, and how strongly they responded to the playbacks. More transient species were attracted to antshrike vocalizations than antwren vocalizations and more transient species were attracted to antwren than control vocalizations. Antshrikes and antwrens approached each others' playback significantly more often than they approached control playbacks; antwrens responded significantly more strongly to antshrike vocalizations than antshrikes did to antwren vocalizations. The primary reason transients are attracted to antshrikes may be the reliable alarm calling of the antshrikes, and the primary reason transient species are attracted to antwrens may be that antwrens serve as an indicator of a flock. Finally, antshrikes and antwrens likely confer benefits to each other, but those benefits may not be symmetrical. Investigating the drivers of space use is critical for understanding the ecology of a species. The drivers of space use patterns of multi-species groups have been studied seldom, although many avian species participate in mixed-species flocks throughout the world. We characterized the space use patterns of mixed-species flocks in Amazonian Peru and investigated the drivers of those patterns. We predicted that foraging and anti-predation behavior, i.e. attack rate, vigilance rate, and surrounding vegetation density of the "leader" Dusky-throated Antshrike (Thamnomanes ardesiacus) would explain the space use patterns of the whole flock. We found that low surrounding vegetation density, but not attack rate or vigilance rate, of the Dusky-throated Antshrike (Thamnomanes ardesiacus) explained a substantial amount of the space use patterns of the flock. The results are consistent with the hypothesis that a single species in these mixed-species flocks has a disproportionately large influence on space use decisions. The results may apply to other flocks worldwide that are led by species that behave similarly to the Dusky-throated Antshrike, for example Asian flocks led by drongos (Dicrurusspp.). Cohesion of interspecific associations requires communication among heterospecifics, although the mechanisms of communication are often unexplored. In many monospecific groups, cohesion among individuals is maintained with contact calls given in a certain context. We investigated whether such context-specific calls are responsible for the cohesion of mixed-species flocks of antshrikes and antwrens in Amazonian Peru. Dusky-throated Antshrikes (Thamnomanes ardesiacus) vocalize while in flight, and the number of times they vocalize covaries with the distance of the flight. Antwrens (Myrmotherula spp.) fly toward an antshrike sooner after the flight call than after a randomized control and another common vocalization not associated with flight. In addition, antwrens fly toward an antshrike sooner after a longer series of flight calls than after a shorter series. It remains unclear whether the antshrikes are deliberately signaling the antwrens or the antwrens are eavesdropping on the vocalizations, although signaling is possible since antshrikes may benefit from associating with antwrens through the dilution effect, confusion effect, and the many-eyes effect. The results suggest that the Dusky-throated Antshrike plays a critical role in maintaining Amazonian biodiversity through positive interactions with many species. Future conservation efforts should aim to conserve the Dusky-throated Antshrike, which likely has a disproportionately large positive effect on many avian species.
Show less

Title: Multi-task learning and its application to geospatio-temporal data
Creator: Xu, Jianpeng
Date: 2017
Collection: Electronic Theses & Dissertations
Description: Multi-task learning (MTL) is a data mining and machine learning approach for modeling multiple prediction tasks simultaneously by exploiting the relatedness among the tasks. MTL has been successfully applied to various domains, including computer vision, healthcare, genomics, recommender systems, and natural language processing. The goals of this thesis are: (1) to investigate the feasibility of applying MTL to geospatio-temporal prediction problems, particularly those encountered in the...
Show moreMulti-task learning (MTL) is a data mining and machine learning approach for modeling multiple prediction tasks simultaneously by exploiting the relatedness among the tasks. MTL has been successfully applied to various domains, including computer vision, healthcare, genomics, recommender systems, and natural language processing. The goals of this thesis are: (1) to investigate the feasibility of applying MTL to geospatio-temporal prediction problems, particularly those encountered in the climate and environmental science domains and (2) to develop novel MTL frameworks that address the challenges of building effective predictive models from geospatio-temporal data.The first contribution of this thesis is to develop an online temporal MTL framework called ORION for ensemble forecasting problems. Ensemble forecasting uses a numerical method to simulate the evolution of nonlinear dynamic systems, such as climate and hydrological systems. ORION aims to effectively aggregate the forecasts generated by different ensemble members for a future time window, where each forecast is obtained by perturbing the starting condition of the computer model or using a different model representation. ORION considers the prediction for each time point in the forecast window as a distinct prediction task, where the task relatedness is achieved by imposing temporal smoothness and mean regularization constraints. A novel, online update with restart strategy is proposed to handle missing observations in the training data. ORION can also be optimized for different objectives, such as ε -insensitive and quantile loss functions.The second contribution of this thesis is to propose a MTL framework named GSpartan that can perform inferences at multiple locations simultaneously while allowing the local models for different locations to be jointly trained. GSpartan assumes that the local models share a common, low-rank representation and employs a graph Laplacian regularization to enforce constraints due to the inherent spatial autocorrelation of the data. Sparsity and non-negativity constraints are also incorporated into the formulation to ensure interpretability of the models.GSpartan is a MTL framework that considers only the spatial autocorrelation of the data. It is also a batch learning algorithm, which makes it difficult to scale up to global-scale data. To address these limitations, a new framework called WISDOM is proposed, which can incorporate the task relatedness across both space and time. WISDOM encodes the geospatio-temporal data as a tensor and performs supervised tensor decomposition to identify the latent factors that capture the inherent spatial and temporal variabilities of the data as well as the relationship between the predictor and target variables. The framework is unique in that it trains distinct spatial and temporal prediction models from the latent factors of the decomposed tensor and aggregates the outputs of these models to obtain the final prediction. WISDOM also employs an incremental learning algorithm that can systematically update the models when training examples are available for a new time period or for a new location.Finally, the geospatio-temporal data for many scientific applications are often available at varying spatial scales. For example, they can be generated by computer models simulated at different grid resolutions (e.g., the global and regional models used in climate modeling). A simple way to handle the predictor variables generated from the multi-scale data is to concatenate them into a single feature vector and train WISDOM using the concatenated vectors. However, this strategy may not be effective as it ignores the inherent dependencies between variables at different scales. To overcome this limitation, this thesis presents an extension of WISDOM called MUSCAT for handling multi-scale geospatio-temporal data. MUSCAT considers the consistency of the latent factors extracted from the spatio-temporal tensors at different scales while inheriting the benefits of WISDOM. Given the massive size of the multi-scale spatio-temporal tensors, a novel, supervised, incremental multi-tensor decomposition algorithm is develop to efficiently learn the model parameters.
Show less

Title: The effect of package dispenser and label on sunscreen application
Creator: Harben, Alyssa Lee
Date: 2017
Collection: Electronic Theses & Dissertations
Description: As skin cancer rates rise, sunscreen use is recommended as a way to decrease the risk of developing skin cancer. Studies show that most consumers of sunscreen do not apply the recommended amount of sunscreen to achieve full protection from UV rays. This study investigates the effect of using two different package dispenser types on human behavior in the context of sunscreen application in an effort to quantify differences in application volume. Additionally, labeling interventions designed to...
Show moreAs skin cancer rates rise, sunscreen use is recommended as a way to decrease the risk of developing skin cancer. Studies show that most consumers of sunscreen do not apply the recommended amount of sunscreen to achieve full protection from UV rays. This study investigates the effect of using two different package dispenser types on human behavior in the context of sunscreen application in an effort to quantify differences in application volume. Additionally, labeling interventions designed to either encourage or discourage application of sunscreen were placed on the bottle to test the effectiveness of using label messaging to influence application amounts. Participants were asked to apply sunscreen from different package styles to their arms and legs and complete a survey regarding the perceived risk of developing skin cancer and frequency of sunscreen use and other demographic factors. Results indicate that participants applied more sunscreen from the squeeze bottles than the pump bottles (p<.0001), and that there was no evidence of a discernable difference between different labels. Of the personal characteristics included in the model (including age, gender, skin tone saturation, history of sun burn, and study location) worry about developing skin cancer and frequency of sunscreen use were also significant at α=.05. The overall findings of this study was packaging design affects sunscreen application practices, but labeling warnings are less influential.
Show less

MSU Libraries

Digital Repository

Enabled Filters

Pages

Pages

MSU Libraries

Digital Repository

You are here

Search results

Pages

Pages