Processing count queries over event streams at multiple time granularities

Management and analysis of streaming data has become crucial with its applications in web, sensor data, network tra c data, and stock market. Data streams consist of mostly numeric data but what is more interesting is the events derived from the numerical data that need to be monitored. The events obtained from streaming data form event streams. Event streams have similar properties to data streams, i.e., they are seen only once in a fixed order as a continuous stream. Events appearing in the event stream have time stamps associated with them in a certain time granularity, such as second, minute, or hour. One type of frequently asked queries over event streams is count queries, i.e., the frequency of an event occurrence over time. Count queries can be answered over event streams easily, however, users may ask queries over di erent time granularities as well. For example, a broker may ask how many times a stock increased in the same time frame, where the time frames specified could be hour, day, or both. This is crucial especially in the case of event streams where only a window of an event stream is available at a certain time instead of the whole stream. In this paper, we propose a technique for predicting the frequencies of event occurrences in event streams at multiple time granularities. The proposed approximation method e ciently estimates the count of events with a high accuracy in an event stream at any time granularity by examining the distance distributions of event occurrences. The proposed method has been implemented and tested on di erent real data sets and the results obtained are presented to show its e ectiveness

EPA Guidelines for Regulatory Impact Analysis

On February 17, 1981, the President issued Executive Order 12291 mandating that regulatory agencies must prepare regulatory impact analyses (RIAs) on all major regulations. Before taking action, the agencies must send all RIAs and proposed regulations to the Office of Management and Budget (OMB) for review. These guidelines discuss the analytical techniques that may be used and the information to be developed by the U.S. Environmental Protection Agency when (l) stating the need for the proposed regulatory action; (2) examining alternative approaches to the problem; (3) quantifying benefits and costs and valuing them in dollar terms (where feasible); and (4) evaluating the findings on benefits, costs, and distributional effects. This document provides guidance for preparing Regulatory Impact Analyses. It includes four appendices and one supplement in addition to the main document.

Situating the Next Generation of Impact Measurement and Evaluation for Impact Investing

In taking stock of the landscape, this paper promotes a convergence of methods, building from both the impact investment and evaluation fields.The commitment of impact investors to strengthen the process of generating evidence for their social returns alongside the evidence for financial returns is a veritable game changer. But social change is a complex business and good intentions do not necessarily translate into verifiable impact.As the public sector, bilaterals, and multilaterals increasingly partner with impact investors in achieving collective impact goals, the need for strong evidence about impact becomes even more compelling. The time has come to develop new mindsets and approaches that can be widely shared and employed in ways that will advance the frontier for impact measurement and evaluation of impact investing. Each of the menu options presented in this paper can contribute to building evidence about impact. The next generation of measurement will be stronger if the full range of options comes into play and the more evaluative approaches become commonplace as means for developing evidence and testing assumptions about the processes of change from a stakeholder perspective– with a view toward context and systems.Creating and sharing evidence about impact is a key lever for contributing to greater impact, demonstrating additionality, and for building confidence among potential investors, partners and observers in this emergent industry on its path to maturation. Further, the range of measurement options offers opportunities to choose appropriate approaches that will allow data to contribute to impact management– to improve on the business model of ventures and to improve services and systems that improve conditions for people and households living in poverty.

Crying over Spilt Milk: A Critical Assessment of the Ecological Modernisation of New Zealand’s Dairy Industry

Ecological modernization theory holds that capitalist economic structures can be transformed to avoid long-term environmental damage, through the introduction of modern environmental technologies and reforming modern institutions. Empirical evidence, drawing on ecological modernization practices in some European and North American contexts, lends support to this view. However, it is not clear yet whether the practices of ecological modernization can be applied with equal success to agricultural industries (such New Zealand's dairy sector), based on farmers as multiple producers. The New Zealand dairy industry faces political and commercial pressure to improve its environmental performance while maintaining commercial competitiveness in a global marketplace. In response to such pressures, the industry's main umbrella organization (Fonterra) has taken steps to improve the environmental management practices of the farmers who supply milk. The New Zealand dairy industry offers an example from which to assess the relevance of economical modernization theory

On Shelf Availability: A Literature Review & Conceptual Framework

On-Shelf Availability (OSA) is a key performance indicator for the retail industry, greatly impacting profit and customer loyalty. Strong competition in the industry causes retailers and suppliers to put heavy emphasis on improving performance in an effort to satisfy consumers and keep them coming back to their store or product. Over 40 years of research has been done on OSA and its complement, out-of stock (OOS), however very little progress has been made in improving performance in these areas, leading to the belief that gaps in extant research exist. In order to solve the OOS problem, the key drivers of OOS events must first be identified and then addressed. This paper focuses on identifying the drivers of poor OSA performance through a three step process. First, a comprehensive literature review was performed to identify the drivers of OOS addressed in existing literature. Second, interviews with industry professionals revealed potential drivers of poor OSA performance that have been explored at an industry level. Finally, the two lists were examined against each other and the potential drivers identified in the interviews that had yet to be researched were highlighted. This paper gives strategic direction for future research to help solve the OOS dilemma facing manufacturers and retailers today

Capital Ownership, Capital Structure and Capital Markets: Financial Constraints and the Decline of the Lancashire Cotton Textile Industry 1880-1965

The objective of this analysis is to provide a reinterpretation of the decline of the Lancashire cotton textile industry during the twentieth century. Its principal concerns are with the governance structure of the industry, the resultant capital structures of firms and the constraints thereby imposed on the activities of entrepreneurs. Its central thesis is that ownership of the industry, and the redistribution of ownership claims during booms and slumps, imposed pressures and constraints on decision-makers. These financial constraints dominated the strategic questions of re-equipment and modernisation