Impacts of extreme weather events on mortgage risks and their evolution under climate change:A case study on Florida

International audienceWe develop an additive Cox proportional hazard model with time-varying covariates, including spatio-temporal characteristics of weather events, to study the impact of weather extremes (heavy rains and tropical cyclones) on the probability of mortgage default and prepayment. We compare the survival model with a flexible logistic model and an extreme gradient boosting algorithm. We estimate the models on a portfolio of mortgages in Florida, consisting of 69,046 loans and 3,707,831 loan-month observations with localization data at the five-digit ZIP code level. We find a statistically significant and non-linear impact of tropical cyclone intensity on default as well as a significant impact of heavy rains in areas with large exposure to flood risks. These findings confirm existing results in the literature and also provide estimates of the impact of the extreme event characteristics on mortgage risk, e.g. the impact of tropical cyclones on default more than doubles in magnitude when moving from a hurricane of category two to a hurricane of category three or more. We build on the identified effect of exposure to flood risk (in interaction with heavy rainfall) on mortgage default to perform a scenario analysis of the future impacts of climate change using the First Street flood model, which provides projections of exposure to floods in 2050 under RCP 4.5. We find a systematic increase in risk under climate change that can vary based on the scenario of extreme events considered. Climate-adjusted credit risk allows risk managers to better evaluate the impact of climate-related risks on mortgage portfolios

An approach to securitisation in Europe NPLs- machine learning model field lab project Nova SBE | moody’s analytics

As a consulting project, we were proposed to develop a neural network (NN) to predict mortgage states in one year, based on the paper ‘Deep Learning for Mortgage Risk’ by Justin A. Sirignano, Apaar Sadhwani, Kay Giesecke (2018). We developed a neural network model with the aim of being able to capture the relationships between the different variables, with respect to each other and to the response variable (the loan status in 12 months), better than traditional classification methods, such as logistic regressions, which constitute the benchmark set. Data was provided by Moody’s, relating borrower, property and loan/financing characteristics for several mortgages over several periods in time (over 350 thousand mortgages). The purpose of our model is to predict the probabilities to transition to different states at a certain point in time. The best results were obtained with a 10 layer, 500 nodes per layer network. The model can identify a large portion of defaults. At the cost, however, of a general overestimation of the default rate over the years. The capability of identifying loans that will be in arrears is also acceptable, with, again, an overestimation of the verified rate. Variables relating to borrower characteristics and history as well as financing are found to be the most significant

The Influence of Collateral on Capital Requirements in the Brazilian Financial System: an approach through historical average and logistic regression on probability of default

Using data drawn from the Brazilian Central Bank Credit Information System, this paper evaluates the impact of the use of collateral on the probability of default and, consequently, on capital requirement levels in the Brazilian financial system. Literature suggests that the existence of collateral in some credit operations increases the debtor's readiness to honor its commitment and, therefore, could result in a lower probability of default. The methodology used to calculate capital requirements is based on the Basel II IRB-Foundation Approach, although the probabilities of default have been estimated by historical averages following Basel II orientation, and corroborated by a logistic regression model. The test of hypothesis about difference between collateralized and uncollateralized probabilities of default for each risk class indicates that they are statistically different. This result was obtained both from historical average probability of default as from logistic regression model.Sob condições específicas, incluindo o requerimento de capital de 11% adotado no Brasil e a Perda dado Default (ou LGD da sigla em inglês) estabelecida em 45%, este artigo também procura identificar um fator de equivalência da razão entre os requerimentos de capital para risco de crédito na Abordagem Padronizada Simplificada e aqueles calculados pela Abordagem Básica do IRB. Para a amostra utilizada, os resultados indicam que operações de não-varejo com garantia possuem uma probabilidade média de default de 2,46% e um fator de equivalência de 60%. Em contrapartida, operações não garantidas possuem uma probabilidade média de default de 6,66% e um fator de equivalência de 93%, aproximando-se bastante do fator de ponderação de 100% da Abordagem Padronizada Simplificada.

Redlining urban neighborhoods : mortgage risk myths or realities

Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 1981.MICROFICHE COPY AVAILABLE IN ARCHIVES AND ROTCH.Bibliography: leaves 272-289.by Harriett Tee Taggart.Ph.D

Improving the Efficiency of Mortgage Loan Modification

A majority of delinquent mortgage loans during the foreclosure crises were unmodified. Lending institutions lost on average 50% of a home\u27s value in future profit from each foreclosure. The purpose of this single case study was to explore what strategies mortgage loan officers might use to improve the selection of delinquent borrowers for mortgage loan modification. The conceptual framework for this study was contract theory. The target population included mortgage loan officers from one community bank who successfully implemented strategies to modify loans for delinquent borrowers during the foreclosure crisis. Semistructured interviews were the data collection method. Emergent themes were identified in the data using a form of pattern matching called explanation building. The following key themes emerged: asymmetric information is essential to a mortgage loan officer\u27s ability to select delinquent borrowers for mortgage loan modification and mortgage loan officers could create value for their organizations through mutually beneficial contracts. The results of this study can be used by leaders in financial institutions to improve the processes and procedures pertaining to mortgage loan modification. Improving mortgage loan modification practices can reduce foreclosure and the impact foreclosures have on the deterioration of communities, property values, and the degraded ability of governments to provide services due to the loss of revenue

Introduction to Data Analytics and Emerging Real-World Use Cases

Data analytics is a rapidly emerging interdisciplinary research area that involves advances in engineering, computer science, statistics and operations research. This webinar is focused on introducing the foundation of data analytics and emerging real-world use cases of data analytics. This presentation will begin with a discussion of the mathematical and statistical modeling aspects of various levels of data analytics (i.e., descriptive, predictive and prescriptive). In this webinar, you will hear an overview of data analytics in real world problems ranging from healthcare analytics, retail analytics and financial analytics

Data Science for Finance: Targeted Learning from (Big) Data to Economic Stability and Financial Risk Management

A thesis submitted in partial fulfillment of the requirements for the degree of Doctor in Information Management, specialization in Statistics and EconometricsThe modelling, measurement, and management of systemic financial stability remains a critical issue in most countries. Policymakers, regulators, and managers depend on complex models for financial stability and risk management. The models are compelled to be robust, realistic, and consistent with all relevant available data. This requires great data disclosure, which is deemed to have the highest quality standards. However, stressed situations, financial crises, and pandemics are the source of many new risks with new requirements such as new data sources and different models. This dissertation aims to show the data quality challenges of high-risk situations such as pandemics or economic crisis and it try to theorize the new machine learning models for predictive and longitudes time series models. In the first study (Chapter Two) we analyzed and compared the quality of official datasets available for COVID-19 as a best practice for a recent high-risk situation with dramatic effects on financial stability. We used comparative statistical analysis to evaluate the accuracy of data collection by a national (Chinese Center for Disease Control and Prevention) and two international (World Health Organization; European Centre for Disease Prevention and Control) organizations based on the value of systematic measurement errors. We combined excel files, text mining techniques, and manual data entries to extract the COVID-19 data from official reports and to generate an accurate profile for comparisons. The findings show noticeable and increasing measurement errors in the three datasets as the pandemic outbreak expanded and more countries contributed data for the official repositories, raising data comparability concerns and pointing to the need for better coordination and harmonized statistical methods. The study offers a COVID-19 combined dataset and dashboard with minimum systematic measurement errors and valuable insights into the potential problems in using databanks without carefully examining the metadata and additional documentation that describe the overall context of data. In the second study (Chapter Three) we discussed credit risk as the most significant source of risk in banking as one of the most important sectors of financial institutions. We proposed a new machine learning approach for online credit scoring which is enough conservative and robust for unstable and high-risk situations. This Chapter is aimed at the case of credit scoring in risk management and presents a novel method to be used for the default prediction of high-risk branches or customers. This study uses the Kruskal-Wallis non-parametric statistic to form a conservative credit-scoring model and to study its impact on modeling performance on the benefit of the credit provider. The findings show that the new credit scoring methodology represents a reasonable coefficient of determination and a very low false-negative rate. It is computationally less expensive with high accuracy with around 18% improvement in Recall/Sensitivity. Because of the recent perspective of continued credit/behavior scoring, our study suggests using this credit score for non-traditional data sources for online loan providers to allow them to study and reveal changes in client behavior over time and choose the reliable unbanked customers, based on their application data. This is the first study that develops an online non-parametric credit scoring system, which can reselect effective features automatically for continued credit evaluation and weigh them out by their level of contribution with a good diagnostic ability. In the third study (Chapter Four) we focus on the financial stability challenges faced by insurance companies and pension schemes when managing systematic (undiversifiable) mortality and longevity risk. For this purpose, we first developed a new ensemble learning strategy for panel time-series forecasting and studied its applications to tracking respiratory disease excess mortality during the COVID-19 pandemic. The layered learning approach is a solution related to ensemble learning to address a given predictive task by different predictive models when direct mapping from inputs to outputs is not accurate. We adopt a layered learning approach to an ensemble learning strategy to solve the predictive tasks with improved predictive performance and take advantage of multiple learning processes into an ensemble model. In this proposed strategy, the appropriate holdout for each model is specified individually. Additionally, the models in the ensemble are selected by a proposed selection approach to be combined dynamically based on their predictive performance. It provides a high-performance ensemble model to automatically cope with the different kinds of time series for each panel member. For the experimental section, we studied more than twelve thousand observations in a portfolio of 61-time series (countries) of reported respiratory disease deaths with monthly sampling frequency to show the amount of improvement in predictive performance. We then compare each country’s forecasts of respiratory disease deaths generated by our model with the corresponding COVID-19 deaths in 2020. The results of this large set of experiments show that the accuracy of the ensemble model is improved noticeably by using different holdouts for different contributed time series methods based on the proposed model selection method. These improved time series models provide us proper forecasting of respiratory disease deaths for each country, exhibiting high correlation (0.94) with Covid-19 deaths in 2020. In the fourth study (Chapter Five) we used the new ensemble learning approach for time series modeling, discussed in the previous Chapter, accompany by K-means clustering for forecasting life tables in COVID-19 times. Stochastic mortality modeling plays a critical role in public pension design, population and public health projections, and in the design, pricing, and risk management of life insurance contracts and longevity-linked securities. There is no general method to forecast the mortality rate applicable to all situations especially for unusual years such as the COVID-19 pandemic. In this Chapter, we investigate the feasibility of using an ensemble of traditional and machine learning time series methods to empower forecasts of age-specific mortality rates for groups of countries that share common longevity trends. We use Generalized Age-Period-Cohort stochastic mortality models to capture age and period effects, apply K-means clustering to time series to group countries following common longevity trends, and use ensemble learning to forecast life expectancy and annuity prices by age and sex. To calibrate models, we use data for 14 European countries from 1960 to 2018. The results show that the ensemble method presents the best robust results overall with minimum RMSE in the presence of structural changes in the shape of time series at the time of COVID-19. In this dissertation’s conclusions (Chapter Six), we provide more detailed insights about the overall contributions of this dissertation on the financial stability and risk management by data science, opportunities, limitations, and avenues for future research about the application of data science in finance and economy