scholarly journals Examining the Impact of Contextual Ambiguity on Search Advertising Keyword Performance: A Topic Model Approach

Author(s):  
Vibhanshu Abhishek ◽  
Jing Gong ◽  
Beibei Li
MIS Quarterly ◽  
2018 ◽  
Vol 42 (3) ◽  
pp. 805-829 ◽  
Author(s):  
Jing Gong ◽  
◽  
Vibhanshu Abhisek ◽  
Beibei Li ◽  
◽  
...  

2020 ◽  
Author(s):  
Stephanie Fern Hudon

Our planet is undergoing rapid change due to the expanding human population and climate change, which leads to extreme weather events and habitat loss. It is more important than ever to develop methods which can monitor the impact we are having on the biodiversity of our planet. To influence policy changes in wildlife and resource management practices we need to provide measurable evidence of how we are affecting animal health and fitness and the ecosystems needed for their survival. We also need to pool our resources and work in interdisciplinary teams to find common threads which can help preserve biodiversity and vital habitats. This dissertation showcases how improved molecular biology assays and data analysis approaches can help monitor the fitness of animal populations within changing ecosystems. Chapter 1 details the development of a universal telomere assay for vertebrates. Recent work has shown the utility of telomere assays in tracking animal health. Telomere lengths can predict extinction events in animal populations, life span, and fitness consequences of anthropogenic activity. Telomere length assays are an improvement over other methods of measuring animal stress, such as cortisol levels, since they are stable during capture and sampling of animals. This dissertation provides a telomere length assay which can be used for any vertebrate. The assay was developed using a quantitative polymerase chain reaction platform which requires low DNA input and is rapid. This dissertation also demonstrates how this assay improves on current telomere assays developed for mice and can be used in a vertebrate not previously assayed for telomere lengths, the American kestrel. This work has the potential to propel research in vertebrate systems forward as it alleviates the need to develop new reference primers for each species of interest. This improved assay has shown promise in studies in mouse cell line studies, American kestrels, golden eagles, five species of passerine birds, osprey, northern goshawks and bighorn sheep. Chapter 2 presents a machine learning analysis, using a topic model approach, to integrate big data from remote sensing, leaf area index surveys, metabolomics and metagenomics to analyze community composition in cross-disciplinary datasets. Topic models were applied to understand community organization across a range of distinct, but connected, biological scales within the sagebrush steppe. The sagebrush steppe is home to several threatened species, including the pygmy rabbit (Brachylagus idahoensis) and sage-grouse (Centrocercus urophasianus). It covers vast swaths of the western United States and is subject to habitat fragmentation and land use conversion for both farming and rangeland use. It is also threatened by increases in fire events which can dramatically alter the landscape. Restoration efforts have been hampered by a lack of resources and often by inadequate collaboration between stakeholders and scientists. This work brought together scientists from four disciplines: remote sensing, field ecology, metabolomics and metagenomics, to provide a framework for how studies can be designed and analyzed that integrate patterns of biodiversity from multiple scales, from the molecular to the landscape scale. A topic model approach was used which groups features (chemicals, bacterial and plant taxa, and light spectrum) into “communities” which in turn can be analyzed for their presence within individual samples and time points. Within the landscape, I found communities which contain encroaching plant species, such as juniper (Juniperus spp.) and cheatgrass (Bromus tectorum). Within plants, I found chemicals which are known toxins to herbivores. Within herbivores, I identified differences in bacterial taxonomical communities associated with changes in diet. This work will help to inform restoration efforts and provide a road map for designing interdisciplinary studies.


2018 ◽  
Vol 3 (1) ◽  
pp. 319-325
Author(s):  
Daniel A. Akansake ◽  
Putri E. Abidin ◽  
E. E. Carey

Abstract This study estimated the amount of loss in storage roots caused by various levels of damage caused by sweetpotato weevils (Cylas spp). Seven varieties of sweetpotato (Ipomoea batatas L. (Lam)) were evaluated in three production sites in northern Ghana for two years (2014 and 2015). Yield data for each experimental plot were collected. A regression analysis was carried out using the generalized linear model approach. In the study, nonmarketable roots were classified as all undersized roots (<100g) and spoilt roots due to weevil, millipede, and soft rot. The results indicated weevil damage as the only significant predictor of nonmarketable yield at 5% level of significance. From the study, the average values for total root yield, marketable root yield, and nonmarketable root yield were 9.39, 6.71, and 2.67 ton/ha respectively. The minimum weevil damage (score 2) resulted in a yield loss of 2 ton/ha which represents 8.3% while severe damage at score 9 could cause a loss of 7.43 ton/ha of storage roots representing 31% of the attainable yield of sweetpotato. Weevil susceptibility needs to be treated as a serious trait when evaluating sweetpotato genotypes to be released as varieties.


2018 ◽  
Vol 141 (5) ◽  
Author(s):  
Yeshaswini Emmi ◽  
Andreas Fiolitakis ◽  
Manfred Aigner ◽  
Franklin Genin ◽  
Khawar Syed

A new model approach is presented in this work for including convective wall heat losses in the direct quadrature method of moments (DQMoM) approach, which is used here to solve the transport equation of the one-point, one-time joint thermochemical probability density function (PDF). This is of particular interest in the context of designing industrial combustors, where wall heat losses play a crucial role. In the present work, the novel method is derived for the first time and validated against experimental data for the thermal entrance region of a pipe. The impact of varying model-specific boundary conditions is analyzed. It is then used to simulate the turbulent reacting flow of a confined methane jet flame. The simulations are carried out using the DLR in-house computational fluid dynamics code THETA. It is found that the DQMoM approach presented here agrees well with the experimental data and ratifies the use of the new convective wall heat losses model.


2017 ◽  
Vol 6 (2) ◽  
pp. 138-147
Author(s):  
Carol Castro

RESUMENInvestigación cualitativa sobre las experiencias de inmigración de 13 mujeres durante sus primeros años en une región nórdica de Quebec. Resultados: El discurso de las mujeres entrevistadas muestra que los principales obstáculos para su integración pasaron por las barreras del idioma, el no reconocimiento de sus diplomas y de sus experiencias laborales en el país de origen, la falta de formación académica adaptada a las mujeres en la región que las acogió y el impacto de las condiciones invernales extremas en la salud psicológica de las mujeres. Conclusión: Es necesario sensibilizar a los profesionales de las ciencias sociales y profesionales de la salud para intervenir a partir del modelo intercultural en poblaciones inmigrantes. ABSTRACTThe article adopts a qualitative approach in studying the immigration trajectories of 13 women during the first years following their arrival in the Quebec region of Abitibi. Results: The testimonies of the female participants show that the main obstacles to their integration in a remote area are linked to linguistic barriers, lack of accreditation of previous degrees and learning, lack of university programs adapted to women and the impact of the region’s harsh winter conditions on psychological well-being. Conclusion: The authors argue for raising awareness among social workers and health professionals in relation to the intercultural model approach. 


2019 ◽  
Vol 1 (1) ◽  
pp. 45-78
Author(s):  
Chankyung Pak

Abstract To disseminate their stories efficiently via social media, news organizations make decisions that resemble traditional editorial decisions. However, the decisions for social media may deviate from traditional ones because they are often made outside the newsroom and guided by audience metrics. This study focuses on selective link sharing as quasi-gatekeeping on Twitter ‐ conditioning a link sharing decision about news content. It illustrates how selective link sharing resembles and deviates from gatekeeping for the publication of news stories. Using a computational data collection method and a machine learning technique called Structural Topic Model (STM), this study shows that selective link sharing generates a different topic distribution between news websites and Twitter and thus significantly revokes the specialty of news organizations. This finding implies that emergent logic, which governs news organizations’ decisions for social media, can undermine the provision of diverse news.


2014 ◽  
Vol 71 (4) ◽  
Author(s):  
Tuti Haryati Jasimin ◽  
Hishamuddin Mohd Ali

The development of sustainable buildings continues to gain momentum in Malaysia due to its many benefits. The Kuala Lumpur City Hall stipulated that the construction of every commercial building must meet the requirements of green features with at least ‘GBI Gold’ level or equivalent. With the growing interest in green development, questions were raised on whether there is enhancement to the market value of green-rated properties and vice-versa. As most of the commercial office buildings are used for functions and office spaces by most organisations, they are considered a service oriented entity and can significantly benefit from having sustainability attributes. Hence, green properties are considered to be more marketable and attractive for investment purpose. However, at present, the differences in rental rates in Malaysia between green and non-green commercial office buildings are rather small. The difference is more to supply and demand factors within the specific location rather than green features factor. Therefore, this paper hopes to highlight the possible impact of economics, the environment and social attributes on the value of commercial office building incorporating with the Russian-Doll model. The highlighted sustainable attributes will provide guidance and justification in valuing real estate incorporating sustainability.


2018 ◽  
Vol 6 (4) ◽  
pp. 98
Author(s):  
Monika Wieczorek-Kosmala ◽  
Joanna Błach ◽  
Joanna Trzęsiok

In previous works, the importance of risk management implementation was addressed with regard to the problem of bankruptcy threat, with the explanation of risk impact on higher bankruptcy costs or the underinvestment problem. However, the evaluation of the impact of risk outcomes is technically linked to risk frequency and risk severity as the two dimensions of the risk map. The purpose of our study is to advocate two additional dimensions that incorporate liquidity and/or debt capacity constraint in the aftermath of risk occurrence. In the conceptual dimension, we propose a model that may support the appropriate design of risk management methods, by scaling a company’s ability to self-resist the risk outcomes. The study provides the empirical illustration of the frequency of the distinguished patterns of risk self-resistance. It was found that most frequently companies face the limited ability to self-resist risk outcomes, due to high debt capacity and high liquidity constraints. We also found statistically significant interdependencies between the company’s sector and the risk self-resistance. It supports the conclusion that the level of liquidity and debt capacity constraints and thus the ability to retain risk outcomes is sector-specific. It has important implications for the effective design of risk management methods.


2019 ◽  
Vol 93 (4) ◽  
pp. 332-352
Author(s):  
Stephen J Macdonald ◽  
Faye Cosgrove

The aim of this article is to explore the impact of dyslexia, self-identified dyslexia and literacy difficulties on police officers/civilian employees. The study employs a social model approach which advocates that problems associated with dyslexia are not due to an impairment effect but can be attributed to a lack of reasonable adjustment due to disabling environmental barriers. The methodology applies a quantitative approach that analyses the impact that dyslexia/literacy difficulties have on policing. The authors suggest that with minor adjustments to working environments, police organisations can foster an inclusive rather than exclusive occupational environment.


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