Mathematical statistics vs machine learning: towards an intelligent modeling framework for soil and plant growth processes

Mestrado de dupla diplomação com a Kuban State Agrarian UniversityThe work described in this dissertation focuses on the methods for analyzing MS and ML that are used in PF. The purpose of the work is to investigate these methods on their practical application to a specific set of data. In the course of the work, the following tasks were completed: the current state of affairs in the field of PF was investigated, the theoretical foundations of the methods of MS and ML were investigated, which were subjected to practical tests on a specific set of data. Conclusions were drawn about the advantages and disadvantages of these methods. A selection of works of scientists engaged in research on the introduction of a specific set of nutrients into the soil was also investigated. The most important contributions to this work are the practical application of various methods of analysis, as well as the design of a DST designed to help farmers integrate PF into their pilot training farms.O trabalho descrito nesta dissertação versa sobre métodos e técnicas no âmbito da Estatística Matemática e de ML usados para efeitos de previsão de colheitas e tratamento de solos em agricultura de precisão. O objetivo do trabalho é investigar esses métodos em sua aplicação prática a um conjunto específico de dados. No decorrer do trabalho, foram realizadas as seguintes tarefas: investigou-se a situação atual no campo da agricultura de precisão, investigaram-se os fundamentos teóricos dos métodos e técnicas da estatística matemática e de ML. Estes métodos e técnicas foram submetidos a testes práticos em um conjunto específico de dados. Foram tiradas conclusões sobre as vantagens e desvantagens desses métodos: Uma seslção de trabalhos científicos relacionados com a investigação sobre a introdução de um conjunto específico de nutrientes no solo foram também investigados. As contribuições mais importantes para este trabalho são a aplicação prática de vários métodos de análise, bem como o projeto de uma ferramenta de apoio à decisão projetada para ajudar os agricultores a integrar a agricultura de precisão nas suas propriedades agrícolas

O impacto da inteligência artificial no negócio eletrónico

Pela importância que a Inteligência Artificial exibe na atualidade, revela-se de grande interesse verificar até que ponto ela está a transformar o Negócio Eletrónico. Para esse efeito, delineou-se uma revisão sistemática com o objetivo de avaliar os impactos da proliferação destes instrumentos. A investigação empreendida pretendeu identificar artigos científicos que, através de pesquisas realizadas a Fontes de Dados Eletrónicas, pudessem responder às questões de investigação implementadas: a) que tipo de soluções, baseadas na Inteligência Artificial (IA), têm sido usadas para melhorar o Negócio Eletrónico (NE); b) em que domínios do NE a IA foi aplicada; c) qual a taxa de sucesso ou fracasso do projeto. Simultaneamente, tiveram de respeitar critérios de seleção, nomeadamente, estar escritos em inglês, encontrarem-se no intervalo temporal 2015/2021 e tratar-se de estudos empíricos, suportados em dados reais. Após uma avaliação de qualidade final, procedeu-se à extração dos dados pertinentes para a investigação, para formulários criados em MS Excel. Estes dados estiveram na base da análise quantitativa e qualitativa que evidenciaram as descobertas feitas e sobre os quais se procedeu, posteriormente, à sua discussão. A dissertação termina com as conclusão e discussão de trabalhos futuros.Due to the importance that Artificial Intelligence exhibits today, it is of great interest to see to what extent it is transforming the Electronic Business. To this end, a systematic review was designed to evaluate the impacts of the proliferation of these instruments. The research aimed to identify scientific articles that, through research carried out on Electronic Data Sources, could answer the research questions implemented: a) what kind of solutions, based on Artificial Intelligence, have been used to improve the Electronic Business; b) in which areas of the Electronic Business Artificial Intelligence has been applied; c) what the success rate or failure of the project is. At the same time, they must comply with selection criteria, to be written in English, to be found in the 2015/2021-time interval and to be empirical studies supported by actual data. After a final quality evaluation, the relevant data for the investigation were extracted for forms created in MS Excel. These data were the basis of the quantitative and qualitative analysis that evidenced the findings found and on which they were subsequently discussed. The dissertation ends with the conclusion and discussion of future works

Learning Representations of Social Media Users

User representations are routinely used in recommendation systems by platform developers, targeted advertisements by marketers, and by public policy researchers to gauge public opinion across demographic groups. Computer scientists consider the problem of inferring user representations more abstractly; how does one extract a stable user representation - effective for many downstream tasks - from a medium as noisy and complicated as social media? The quality of a user representation is ultimately task-dependent (e.g. does it improve classifier performance, make more accurate recommendations in a recommendation system) but there are proxies that are less sensitive to the specific task. Is the representation predictive of latent properties such as a person's demographic features, socioeconomic class, or mental health state? Is it predictive of the user's future behavior? In this thesis, we begin by showing how user representations can be learned from multiple types of user behavior on social media. We apply several extensions of generalized canonical correlation analysis to learn these representations and evaluate them at three tasks: predicting future hashtag mentions, friending behavior, and demographic features. We then show how user features can be employed as distant supervision to improve topic model fit. Finally, we show how user features can be integrated into and improve existing classifiers in the multitask learning framework. We treat user representations - ground truth gender and mental health features - as auxiliary tasks to improve mental health state prediction. We also use distributed user representations learned in the first chapter to improve tweet-level stance classifiers, showing that distant user information can inform classification tasks at the granularity of a single message.Comment: PhD thesi

Learning Representations of Social Media Users

User representations are routinely used in recommendation systems by platform developers, targeted advertisements by marketers, and by public policy researchers to gauge public opinion across demographic groups. Computer scientists consider the problem of inferring user representations more abstractly; how does one extract a stable user representation - effective for many downstream tasks - from a medium as noisy and complicated as social media? The quality of a user representation is ultimately task-dependent (e.g. does it improve classifier performance, make more accurate recommendations in a recommendation system) but there are proxies that are less sensitive to the specific task. Is the representation predictive of latent properties such as a person's demographic features, socioeconomic class, or mental health state? Is it predictive of the user's future behavior? In this thesis, we begin by showing how user representations can be learned from multiple types of user behavior on social media. We apply several extensions of generalized canonical correlation analysis to learn these representations and evaluate them at three tasks: predicting future hashtag mentions, friending behavior, and demographic features. We then show how user features can be employed as distant supervision to improve topic model fit. Finally, we show how user features can be integrated into and improve existing classifiers in the multitask learning framework. We treat user representations - ground truth gender and mental health features - as auxiliary tasks to improve mental health state prediction. We also use distributed user representations learned in the first chapter to improve tweet-level stance classifiers, showing that distant user information can inform classification tasks at the granularity of a single message.Comment: PhD thesi

Strategic Hedging and Middle Power Foreign Policy: The Case of Thailand as Viewed Through Neoclassical Realism

The Sino-American competition poses a challenge for all states, including Thailand. As a Southeast Asian middle power, Thailand must balance long-term security and short-term economic interests. Strategic hedging, deeply rooted in Thai history, involves engaging with competing great powers. This thesis explores Bangkok's foreign policy by examining its past, using neoclassical realist theory to analyze policy development and external factors. By studying centuries of strategy, this thesis fills a gap in literature on hedging and offers insights into Thailand's approach to the superpower rivalry

Concerning Beards

This Open Access book provides a new understanding of the meanings and motivations behind the wearing of beards, moustaches and whiskers, and their associated practices and practitioners. Concerning Beards offers an important new long-term perspective on health and the male body in British society. It argues that the male face has long been an important site for the articulation of bodily health and vigour, as well as masculinity. Through an exploration of the history of male facial hair in England, Alun Withey underscores its complex meanings, medical implications and socio-cultural significance from the mid-17th to the early 20th century. Herein, he charts the gradual shift in concepts of facial hair and shaving - away from ‘formal’ medicine and practice - towards new concepts of hygiene and personal grooming. The ebook editions of this book are available open access under a CC BY-NC-ND 3.0 licence on bloomsburycollections.com. Open access was funded by the Wellcome Trust. This book is part of the Facialities series, which explores the social, cultural and political significance of the face in human history

Front-Line Physicians' Satisfaction with Information Systems in Hospitals

Day-to-day operations management in hospital units is difficult due to continuously varying situations, several actors involved and a vast number of information systems in use. The aim of this study was to describe front-line physicians' satisfaction with existing information systems needed to support the day-to-day operations management in hospitals. A cross-sectional survey was used and data chosen with stratified random sampling were collected in nine hospitals. Data were analyzed with descriptive and inferential statistical methods. The response rate was 65 % (n = 111). The physicians reported that information systems support their decision making to some extent, but they do not improve access to information nor are they tailored for physicians. The respondents also reported that they need to use several information systems to support decision making and that they would prefer one information system to access important information. Improved information access would better support physicians' decision making and has the potential to improve the quality of decisions and speed up the decision making process.Peer reviewe