295 research outputs found
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Five Years Later: Lessons from the Financial Crisis
The deepest economic collapse in 75 years occurred because of a widespread failure across the financial system rather than a single cause. In order to safeguard the economy in the future, I propose in this paper that strong regulation, implementation and enforcement of systemic protections and emergency lending capabilities are needed. I examine the problems that converged to create the financial crisis, and provide 10 insights from that period. Among the causes of the crisis I examine: global imbalances, a housing bubble, loose monetary policy, a very large increase in short-term market financing of broker dealers and portfolios, excessive leverage, and shadow banking. The paper provides new insight into how the crisis is connected to the fall of residential mortgage-backed securities prices and their drop in value as collateral. It also discusses the connection to incentive compensation and to opacity driven by complex financial instruments such as collateralized debt obligations (CDOs), derivatives, and exotic mortgages, which may not have been fully understood by many who dealt with them, including those who designed them
Crafting A Human Resource Strategy To Foster Organizational Agility: A Case Study
A decade ago, the CEO of Albert Einstein Healthcare Network (AEHN), anticipating a tumultuous and largely unpredictable period in its industry, undertook to convert this organization from one that was basically stable and complacent to one that was agile, “nimble, and change-hardy”. This case study briefly addresses AEHN’s approaches to business strategy and organization design, but focuses primarily on the human resource strategy that emerged over time to foster the successful attainment of organizational agility. Although exploratory, the study suggests a number of lessons for those who are, or will be, studying or trying to create and sustain this promising new organizational paradigm
A storage architecture for data-intensive computing
The assimilation of computing into our daily lives is enabling the generation of data at unprecedented rates. In 2008, IDC estimated that the "digital universe" contained 486 exabytes of data [9]. The computing industry is being challenged to develop methods for the cost-effective processing of data at these large scales. The MapReduce programming model has emerged as a scalable way to perform data-intensive computations on commodity cluster computers. Hadoop is a popular open-source implementation of MapReduce. To manage storage resources across the cluster, Hadoop uses a distributed user-level filesystem. This filesystem --- HDFS --- is written in Java and designed for portability across heterogeneous hardware and software platforms. The efficiency of a Hadoop cluster depends heavily on the performance of this underlying storage system.
This thesis is the first to analyze the interactions between Hadoop and storage. It describes how the user-level Hadoop filesystem, instead of efficiently capturing the full performance potential of the underlying cluster hardware, actually degrades application performance significantly. Architectural bottlenecks in the Hadoop implementation result in inefficient HDFS usage due to delays in scheduling new MapReduce tasks. Further, HDFS implicitly makes assumptions about how the underlying native platform manages storage resources, even though native filesystems and I/O schedulers vary widely in design and behavior. Methods to eliminate these bottlenecks in HDFS are proposed and evaluated both in terms of their application performance improvement and impact on the portability of the Hadoop framework.
In addition to improving the performance and efficiency of the Hadoop storage system, this thesis also focuses on improving its flexibility. The goal is to allow Hadoop to coexist in cluster computers shared with a variety of other applications through the use of virtualization technology. The introduction of virtualization breaks the traditional Hadoop storage architecture, where persistent HDFS data is stored on local disks installed directly in the computation nodes. To overcome this challenge, a new flexible network-based storage architecture is proposed, along with changes to the HDFS framework. Network-based storage enables Hadoop to operate efficiently in a dynamic virtualized environment and furthers the spread of the MapReduce parallel programming model to new applications
Quantifying the impact of dissimilar HPV vaccination uptake among Manitoban school girls by ethnicity using a transmission dynamic model
BACKGROUND: Gardasil, a human papillomavirus (HPV) vaccine, began among grade 6 girls in Manitoba, Canada in 2008. In Manitoba, there is evidence that First Nations, Metis, and Inuit women (FNMI) have higher HPV prevalence, lower invasive cervical cancer (ICC) screening, and higher ICC incidence than all other Manitoban (AOM) women. We developed a mathematical model to assess the plausible impact of unequal vaccination coverage among school girls on future cervical cancer incidence. METHODS: We fit model estimated HPV prevalence and ICC incidence to corresponding empirical estimates. We used the fitted model to evaluate the impact of varying levels of vaccination uptake by FNMI status on future ICC incidence, assuming cervical screening uptake among FNMI and AOM women remained unchanged. RESULTS: Depending on vaccination coverage, estimated ICC incidence by 2059 ranged from 15% to 68% lower than if there were no vaccination. The level of cross-ethnic sexual mixing influenced the impact that vaccination rates among FNMI has on ICC incidence among AOM, and vice versa. The same level of AOM vaccination could result in ICC incidence that differs by up to 10%, depending on the level of FNMI vaccination. Similarly, the same level of FNMI vaccination could result in ICC incidence that differs by almost 40%, depending on the level of AOM vaccination. CONCLUSIONS: If we are unable to equalize vaccination uptake among all school girls, policy makers should prepare for higher levels of cervical cancer than would occur under equal vaccination uptak
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