The migratory birds stop at different stopover sites during migration. The presence of resources in these stopover sites is essential to regain the energy of these birds. This thesis aims to compare the resource abundance and intake at the two stopover sites: Reda and Wisla river estuaries. How a bird's mass changes during its stay at an estuary is considered as a proxy for the resource abundance of a site. The comparison is made on different subsets, including those which has incomplete data, i.e. next day is not exactly one day after the previous capture. Multiple linear regression, Generalized additive model and Linear mixed effect model are used for analysis. Expectation maximization and an iterative predictive process are implemented to deal with incomplete data. We found that Reda has higher resource abundance and intake as compared to that of Wisla river estuary.

El presente trabajo de investigación tiene como objetivo aplicar técnicas de análisis de regresión y aprendizaje automático (ML) para mejorar los resultados de estimación de sobre dilución en tajos explotados por el método de Sub Level Stoping (SLS) de la Compañía Minera Condestable (CMC) a través de la generación de ecuaciones de regresión y código en lenguaje de Python para las técnicas de ML. Para la estimación de sobre dilución se analizaron las reconciliaciones de tajos explotados con el método de SLS del período 2017-2019 con la aplicación de las técnicas: Análisis de Regresión Lineal Múltiple (ARLM), regresión no lineal múltiple (ARNM) y métodos de aprendizaje automático (ML) como Máquinas de Vectores de Soporte (SVM) y bosques aleatorios (RF), lo que permitió establecer comparaciones entre los resultados a nivel predictivo y tecnológico con la metodología de O’Hara aplicada actualmente en CMC para la estimación de sobre dilución de tajos SLS. La aplicación de las técnicas mencionadas implicó variables operativas como: nivel, buzamiento, densidad, burden, espaciamiento, altura, longitud, ancho, RQD, RMR y ratio de tonelada por metro de perforación (TMP) de los tajos evaluados, mientras que el objetivo o variable dependiente fue la sobre dilución. Ello permitió inicialmente identificar que las técnicas de regresión ARLM y ARNM mejoraron el coeficiente de determinación R2 de O’Hara en 5.5% y 4.4%. Luego, con la aplicación de herramientas de aprendizaje automático se identificó que ambas técnicas (SVM y RF) lograron la mejora en 0.3% y 18.5% respectivamente. El resultado de ello fue la reducción de la diferencia de costos estimados obtenidos con la metodología de O’Hara relacionados al costo adicional por carguío y transporte de carga rota de dilución. / This research work aims to apply Regression Analysis and Machine Learning (ML) techniques to improve the results of estimating over dilution in stopes mined by Sub Level Stoping (SLS) method at Compania Minera Condestable (CMC) through the generation of regression equations and code in Python language for ML techniques. For the estimation of over dilution, the reconciliations of stopes mined with the SLS method for the period 2017-2019 were analysed with the application of the techniques: Multiple Linear Regression Analysis (MLRA), Multiple Non-linear Regression Analysis (MLNRA) and Machine Learning (ML) methods such as Support Vector Machine (SVM) and Random Forests (RF), which allowed comparisons of the results at predictive and technological level with the O'Hara methodology currently applied at CMC for the estimation of over dilution of SLS stopes. The application of the afore mentioned techniques involved operational variables such as: level, dip, density, burden, spacing, height, length, width, RQD, RMR and tonne per metre drilling (TMP) ratio of the evaluated stopes, while the objective or dependent variable was over dilution. This initially identified that the ARLM and ARNM regression techniques improved O'Hara's R2 determination coefficient by 5.5% and 4.4%. Then, with the application of machine learning tools it was identified that both techniques (SVM and RF) achieved the improvement by 0.3% and 18.5% respectively. This resulted in a reduction of the estimated cost difference obtained with the O'Hara methodology related to the additional cost of loading and transporting broken stock from the dilution. / Tesis

El presente trabajo muestra la situación actual de la demanda de Gas Liquado de Petroleo (GLP) en el mercado peruano con respecto al parque automotor durante los últimos 6 años. El objetivo general es predecir la demanda de GLP para el segundo semestre del año 2021, a través de las variables más relevantes a fin de conocer si la producción local más la importación de este tipo de combustible (GLP) será la suficiente para cubrir la demanda del sector automotriz. La metodología utilizada por el equipo de ciencia de datos es Cross Industry Standard Process for Data Mining (CRISP-DM), la cual consiste en seguir una serie de diez etapas, en cada una de ellas se ira descubriendo y analizando las variables que serán relevantes para la elaboración del modelo deseado. El modelo seleccionado por el equipo de ciencia de datos es el modelo de aprendizaje predictivo ya que este agrupa varias técnicas estadísticas de modelización, lo cual incluye algoritmos de aprendizaje automático. Posteriormente las Herramientas que se utilizarán para un mejor Análisis y entendimiento de la problemática serán Power BI, KNime y Python. / This paper shows the current situation of Liquefied Petroleum Gas (LPG) demand in the Peruvian market with respect to the vehicle fleet during the last 6 years. The general objective is to predict the LPG demand for the second semester of the year 2021, through the most relevant variables to know if the local production plus the import of this type of fuel (LPG) will be enough to cover the demand of the automotive sector. The methodology used by the data science team is Cross Industry Standard Process for Data Mining (CRISP-DM), which consists of following a series of ten stages, in each of which the variables that will be relevant for the elaboration of the desired model will be discovered and analyzed. The model selected by the data science team is the predictive learning model because it groups several statistical modeling techniques, including machine learning algorithms. Subsequently, the tools to be used for a better analysis and understanding of the problem will be Power BI, KNime and Python. / Trabajo de investigación

Why do strong states, despite their far superior military capabilities, experience increasing difficulties in defeating small states in asymmetric conflicts? In this thesis I develop a conceptual framework based on Keohane & Nye's theory of complex interdependence, in which I argue that the increased degree of mutual interdependence among strong states leads to decreased cost-tolerance when exercising military power. This, in turn, leads to power being exercised in other forms such as different types of sanctions, influence on political agendas or through political pressure made possible by asymmetric vulnerabilities. The conceptual framework is tested with descriptive statistics and multiple linear regression on all 118 cases of asymmetric conflicts fought between 1945 and 2003. The results challenge existing knowledge about factors such as the importance of military power, troop commitment, external support, the nature of government and freedom of the press. At the same time, risks are identified in small states’ strategies that are based on external support. The result of the study indicates that such strategies lead to increased cost-tolerance among strong intervening states.

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Supply chain operations of construction industry including road projects in disaster regions results in exceeding project budget and timelines. In road construction projects, supply chain with poor performance can affect efficiency and completion time of the project. This is also the case of the road projects in disaster areas. Disaster areas consider both natural and man-made disasters. Few examples of disaster zones are; Pakistan, Afghanistan, Iraq, Sri Lanka, India, Japan, Haiti and many other countries with similar environments. The key factors affecting project performance and execution are insecurity, uncertainties in demand and supply, poor communication and technology, poor infrastructure, lack of political and government will, unmotivated organizational staff, restricted accessibility to construction materials, legal hitches, multiple challenges of hiring labour force and exponential construction rates due to high risk environment along with multiple other factors. The managers at all tiers are facing challenges of overrunning time and budget of supply chain operations during planning as well as execution phase of development projects. The aim of research is to develop a Multiple Linear Regression Model (MLRM) and a Rule Based Decision Support System by incorporating various factors affecting supply chain management of road projects in disaster areas in the order of importance. This knowledge base (KB) (importance / coefficient of each factor) will assist infrastructure managers (road projects) and practitioners in disaster regions in decision making to minimize the effect of each factor which will further help them in project improvement. Conduct of Literature Review in the fields of disaster areas, supply chain operational environments of road project, statistical techniques, Artificial Intelligence (AI) and types of research approaches has provided deep insights to the researchers. An initial questionnaire was developed and distributed amongst participants as pilot project and consequently results were analysed. The results’ analysis enabled the researcher to extract key variables impacting supply chain performance of road project. The results of questionnaire analysis will facilitate development of Multiple Linear Regression Model, which will eventually be verified and validated with real data from actual environments. The development of Multiple Linear Regression Model and Rule Based Decision Support System incorporating all factors which affect supply chain performance of road projects in disastrous regions is the most vital contribution to the research. The significance and novelty of this research is the methodology developed that is the integration of those different methods which will be employed to measure the SCM performance of road projects in disaster areas.

The Mississippi River Valley Alluvial Aquifer (MRVAA) is one of the most productive agricultural regions in the United States. The main objectives of this research are to identify long term trends and change points in hydrological variables (streamflow and rainfall), to assess the relationship between hydrological variables, and to evaluate the influence of global climate indices on hydrological variables. Non-parametric tests, MMK and Pettitt’s tests were used to analyze trend and change points. PCC and Streamflow elasticity analysis were used to analyze the relationship between streamflow and rainfall and the sensitivity of streamflow to rainfall changes. PCC and MLR analysis were used to evaluate the relationship between climate indices and hydrological variables and the combined effect of climate indices with hydrological variables. The results of the trend analysis indicated spatial variability within the aquifer, increase in streamflow and rainfall in the Northern region of the aquifer, while a decrease was observed in the southern region of the aquifer. Change point analysis of annual maximum, annual mean streamflow and annual precipitation revealed that statistically decreasing shifts occurred in 2001, 1998 and 1995, respectively. Results of PCC analysis indicated that streamflow and rainfall has a strong positive relationship between them with PCC values more than 0.6 in most of the locations within the basin. Results of the streamflow elasticity for the locations ranged from 0.987 to 2.33 for the various locations in the basin. Results of the PCC analysis for monthly maximum and mean streamflow showed significant maximum positive correlation coefficient for Nino 3.4. Monthly maximum rainfall showed a maximum significant positive correlation coefficient for PNA and Nino3.4 and the monthly mean rainfall showed a maximum significant positive correlation coefficient of 0.18 for Nino3.4. Results of the MLR analysis showed a maximum significant positive correlation coefficient of 0.31 for monthly maximum and mean streamflow of 0.21 and 0.23 for monthly maximum and mean rainfall, respectively. Overall, results from this research will help in understanding the impacts of global climate indices on rainfall and subsequently on streamflow discharge, so as to mitigate and manage water resource availability in the MRVAA underlying the LMRB.

This thesis examines which factors drive overall net inflows to a Swedish niche bank. It further investigates whether these factors are the same or different from the factors that drive net inflows to mutual funds as well as shares. To find the key factors, and to what degree they drive the different net inflows, three separate multiple linear regressions were performed. The data analysed was taken from the period January 2018 to February 2022, and was provided by Avanza Bank. The data for the driving factors were gathered from different sources online. 21 regressors were used for this analysis. The thesis conclusion in brief was that for total net inflows the main contributor was the number of customers, which positively impacted the net inflows. The two subcategories: mutual fund and stock inflows were more volatile and the number of customers proved not as important in these cases. Some seasonal patterns were recognized, e.g. January was always a significant month for total net inflows. Therefore, performing a time series analysis would be recommended to draw further conclusions. Other possible avenues for future research is to gain a deeper understanding of this applied area of mathematics and to gather more data both in terms of the analysed time period and number of regressors. / Detta arbete ämnar undersöka vilka faktorer som generellt driver nettoflöden till en svensk nischbank. Arbetet ämnar även att vidare undersöka om dessa eller andra faktorer är mest drivande för nettoflöden till kategorierna fonder och aktier. För att hitta dessa nyckelfaktorer, samt till vilken grad de driver nettoflöden, utfördes tre stycken regressionsanalyser. Datan som analyserades avsåg tidsperioden januari 2018 till februari 2022 och sammanställdes av Avanza Bank. Samtliga potentiella nyckelfaktorer för nettoinflödet samlades in från diverse källor online, totalt användes 21 stycken regressorer för analysen. Arbetets slutsats i korthet var att det för det totala nettoflöden är bankens totala antal kunder som är den största drivande faktorn, vilket har ett positivt samband med den beroende variabeln. För de två sub-kategorierna, nettoflöden till fonder och aktier var det svårare att bygga en modell och antal kunder visade sig inte ha en stor påverkan för dessa. Ett säsongsmönster kunde observeras i datan, exempelvis var januari alltid en signifikant månad för stora nettoflöden. Med detta som bakgrund kunde ett tidsserieanalys rekommenderas för att kunna dra bättre slutsatser inom ämnet. Andra möjliga alternativ för framtida forskning innefattar en djupare analys inom detta område av tillämpad matematik samt insamling av mer data både i fråga om den studerade tidsperioden samt antalet använda regressorer.

Investing in public real estate stocks can diversify a stock portfolio due to the nature of these companies. The industry is generally less sensitive to economic downturns and spikes in inflation are offset by increased real estate property and rent prices. Nevertheless, measures of the wider economy could be used as predictors of the real estate stock market.  This thesis attempts to model the Swedish real estate stock market with the index SX35PI (Stockholm Real Estate PI) using the fundamental economic factors and repo rate. Data was collected and formatted to a monthly interval for the period February 2012 to December 2021. This resulted in an exponential multiple regression model that used all the regressors that explained 95.7% of the variation in SX35PI, and an alternative autoregressive forecasting model that explained 82.3% of the variation in SX35PI. / Investeringar i fastighetsbolag kan diversifiera en aktieportfölj tack vare dessa bolags karaktär. Denna industri är nämligen mindre känslig för ekonomiska nedgångar och minskad efterfråga samt plötsliga ökningar i inflationen som vägs upp av ökningar i fastighetspriser och hyror. Aktiemarknaden för fastighetsaktier kan modelleras med makroekonomiska mått. Denna rapport försöker modellera aktiemarknaden för svenska fastighetsbolag med fundamentala ekonomiska mått samt reporäntan. Data samlades och transformerades för att få datapunkter varje månad under februari 2012 till december 2021. Resultatet blev en exponentiell multipel regressionsmodell som använde alla förklarande variabler vilka förklarade 95.7% av variationen i SX35PI, och en alternativ autoregressiv modell som förklarade 82.3% av variationen i SX35PI.