Bringing power and progress to Africa in a financially and environmentally sustainable manner

EXECUTIVE SUMMARY: The future of electricity supply and delivery on the continent of Africa represents one of the thorniest challenges facing professionals in the global energy, economics, finance, environmental, and philanthropic communities. Roughly 600 million people in Africa lack any access to electricity. If this deficiency is not solved, extreme poverty for many Africans is virtually assured for the foreseeable future, as it is widely recognized that economic advancement cannot be achieved in the 21st Century without good electricity supply. Yet, if Africa were to electrify in the same manner pursued in developed economies around the world during the 20th Century, the planet’s global carbon budget would be vastly exceeded, greatly exacerbating the worldwide damages from climate change. Moreover, due to low purchasing power in most African economies and fiscal insolvency of most African utilities, it is unclear exactly how the necessary infrastructure investments can be deployed to bring ample quantities of power – especially zero-carbon power – to all Africans, both those who currently are unconnected to any grid as well as those who are now served by expensive, high-emitting, limited and unreliable electricity supply. With the current population of 1.3 billion people expected to double by 2050, the above-noted challenges associated with the African electricity sector may well get substantially worse than they already are – unless new approaches to infrastructure planning, development, finance and operation can be mobilized and propagated across the continent. This paper presents a summary of the present state and possible futures for the African electricity sector. A synthesis of an ever-growing body of research on electricity in Africa, this paper aims to provide the reader a thorough and balanced context as well as general conclusions and recommendations to better inform and guide decision-making and action. [TRUNCATED]This paper was developed as part of a broader initiative undertaken by the Institute for Sustainable Energy (ISE) at Boston University to explore the future of the global electricity industry. This ISE initiative – a collaboration with the Global Energy Interconnection and Development Cooperation Organization (GEIDCO) of China and the Center for Global Energy Policy within the School of International and Public Affairs at Columbia University – was generously enabled by a grant from Bloomberg Philanthropies. The authors gratefully acknowledge the support and contributions of the above funders and partners in this research

Practical Batch Bayesian Sampling Algorithms for Online Adaptive Traffic Experimentation

Online controlled experiments have emerged as industry gold standard for assessing new web features. As new web algorithms proliferate, experimentation platform faces an increasing demand on the velocity of online experiments, which encourages adaptive traffic testing methods to speed up identifying best variant by efficiently allocating traffic. This paper proposed four Bayesian batch bandit algorithms (NB-TS, WB-TS, NB-TTTS, WB-TTTS) for eBay's experimentation platform, using summary batch statistics of a goal metric without incurring new engineering technical debts. The novel WB-TTTS, in particular, demonstrates as an efficient, trustworthy and robust alternative to fixed horizon A/B testing. Another novel contribution is to bring trustworthiness of best arm identification algorithms into evaluation criterion and highlight the existence of severe false positive inflation with equivalent best arms. To gain the trust of experimenters, experimentation platform must consider both efficiency and trustworthiness; However, to the best of authors' knowledge, trustworthiness as an important topic is rarely discussed. This paper shows that Bayesian bandits without neutral posterior reshaping, particularly naive Thompson sampling (NB-TS), are untrustworthy because they can always identify an arm as the best from equivalent best arms. To restore trustworthiness, a novel finding uncovers connections between convergence distribution of posterior optimal probabilities of equivalent best arms and neutral posterior reshaping, which controls false positives. Lastly, this paper presents lessons learned from eBay's experience, as well as thorough evaluations. We hope this work is useful to other industrial practitioners and inspires academic researchers interested in the trustworthiness of adaptive traffic experimentation

Moving Metric Detection and Alerting System at eBay

At eBay, there are thousands of product health metrics for different domain teams to monitor. We built a two-phase alerting system to notify users with actionable alerts based on anomaly detection and alert retrieval. In the first phase, we developed an efficient anomaly detection algorithm, called Moving Metric Detector (MMD), to identify potential alerts among metrics with distribution agnostic criteria. In the second alert retrieval phase, we built additional logic with feedbacks to select valid actionable alerts with point-wise ranking model and business rules. Compared with other trend and seasonality decomposition methods, our decomposer is faster and better to detect anomalies in unsupervised cases. Our two-phase approach dramatically improves alert precision and avoids alert spamming in eBay production.Comment: The work is oral presented on the AAAI-20 Workshop on Cloud Intelligence, 202

Understanding fragmentation of prostate cancer survivorship care

BACKGROUND: Cancer survivors are particularly prone to the effects of a fragmented health care delivery system. The implications of fragmented cancer care across providers likely include greater spending and worse quality of care. For this reason, the authors measured relations between increasing fragmentation of cancer care, expenditures, and quality of care among prostate cancer survivors. METHODS: A total of 67,736 patients diagnosed with prostate cancer between 1992 and 2005 were identified using Surveillance, Epidemiology, and End Results (SEER)‐Medicare data. Using the Herfindahl‐Hirschman Index and a measure of the average number of prostate cancer providers over time, patients were sorted into 3 fragmentation groups (low, intermediate, and high). The authors then examined annual per capita survivorship expenditures and a measure of quality (ie, repetitive prostate‐specific antigen [PSA] testing within 30 days) according to their fragmentation exposure using multinomial logistic regression. RESULTS: Patients with highly fragmented cancer care tended to be younger, white, and of higher socioeconomic status (all P < .001). Prostate cancer survivorship interventions were most common among patients with the highest fragmentation of care across providers ( P < .001). After adjustment for clinical characteristics and prostate cancer survivorship interventions, higher degrees of fragmentation continued to be associated with repetitive PSA testing (13.6% for high vs 7.0% for low fragmentation; P < .001) and greater spending, particularly among patients not treated with androgen deprivation therapy. CONCLUSIONS: Fragmented prostate cancer survivorship care is expensive and associated with potentially unnecessary services. Efforts to improve care coordination via current policy initiatives, electronic medical records, and the implementation of cancer survivorship tools may help to decrease fragmentation of care and mitigate downstream consequences for prostate cancer survivors. Cancer 2011;. © 2011 American Cancer Society. Fragmented prostate cancer survivorship care is expensive and associated with potentially unnecessary services. Efforts to improve care coordination via current policy initiatives, electronic medical records, and the implementation of cancer survivorship tools may help to decrease fragmentation of care and mitigate downstream consequences for prostate cancer survivors.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/91344/1/26601_ftp.pd