Carnegie Mellon University

About: Carnegie Mellon University is a education organization based out in Pittsburgh, Pennsylvania, United States. It is known for research contribution in the topics: Computer science & Robot. The organization has 36317 authors who have published 104359 publications receiving 5975734 citations. The organization is also known as: CMU & Carnegie Mellon.

Political resource allocation, controlled agendas, and the status quo

Abstract: Economic analysis requires modelling political as well as market resource allocation. Voting institutions, in particular two-candidate majority rule elections and voting on motions, have been a primary focus of recent analytical developments. In the case of a single good to be allocated politically, standard assumptions lead to 'single-peakedness' of voter preferences over the set of alternatives. When, in choosing between a pair of available alternatives, every voter votes for his preferred alternative, the allocative equilibrium is the 'Condorcet point' or political allocation most desired by the median voter (Bowen, 1943; Black, 1958; Riker and Ordeshook, 1973). This result concerning the dominance of the median voter's ideal allocation depends importantly on the nature of competition in the allocation process. In the context of the political allocation of economic goods, the 'median voter' outcome is typically justified on the basis of an underlying but usually unmodeled process of political competition between two candidates for elective office, wherein the dominant strategy for each candidate is to offer to provide the level of public spending that corresponds to the median voter's ideal expenditure. Such a view of equilibrium under majority rule (when equilibrium exists) may be very unrepresentative of political processes. Many such processes, particularly those related to collective expenditure determination, may be more appropriately characterized as ones in which some group has the power to make a proposal to the voters, and thereby set the agenda. This group, which we call the agenda setter, by having monopoly power over the proposal placed before the electorate, can confront the voters with a 'take it or leave it' choice. Because 'competitive' substitutes to the setter's proposal are not offered, the median voter cannot simply 'hold out' until the Condorcet point is proposed. When the setter has monopoly power, voters are forced to choose between

A Survey of Statistical Network Models

Abstract: Networks are ubiquitous in science and have become a focal point for discussion in everyday life. Formal statistical models for the analysis of network data have emerged as a major topic of interest in diverse areas of study, and most of these involve a form of graphical representation. Probability models on graphs date back to 1959. Along with empirical studies in social psychology and sociology from the 1960s, these early works generated an active "network community" and a substantial literature in the 1970s. This effort moved into the statistical literature in the late 1970s and 1980s, and the past decade has seen a burgeoning network literature in statistical physics and computer science. The growth of the World Wide Web and the emergence of online "networking communities" such as Facebook, MySpace, and LinkedIn, and a host of more specialized professional network communities has intensified interest in the study of networks and network data. Our goal in this review is to provide the reader with an entry point to this burgeoning literature. We begin with an overview of the historical development of statistical network modeling and then we introduce a number of examples that have been studied in the network literature. Our subsequent discussion focuses on a number of prominent static and dynamic network models and their interconnections. We emphasize formal model descriptions, and pay special attention to the interpretation of parameters and their estimation. We end with a description of some open problems and challenges for machine learning and statistics.

An empirical study of speed and communication in globally distributed software development

Abstract: Global software development is rapidly becoming the norm for technology companies. Previous qualitative research suggests that distributed development may increase development cycle time for individual work items (modification requests). We use both data from the source code change management system and survey data to model the extent of delay in a distributed software development organization and explore several possible mechanisms for this delay. One key finding is that distributed work items appear to take about two and one-half times as long to complete as similar items where all the work is colocated. The data strongly suggest a mechanism for the delay, i.e., that distributed work items involve more people than comparable same-site work items, and the number of people involved is strongly related to the calendar time to complete a work item. We replicate the analysis of change data in a different organization with a different product and different sites and confirm our main findings. We also report survey results showing differences between same-site and distributed social networks, testing several hypotheses about characteristics of distributed social networks that may be related to delay. We discuss implications of our findings for practices and collaboration technology that have the potential for dramatically speeding distributed software development.

DAML-S: Web Service Description for the Semantic Web

Abstract: In this paper we present DAML-S, a DAML+OIL ontology for describing the properties and capabilities of Web Services. Web Services - Web-accessible programs and devices - are garnering a great deal of interest from industry, and standards are emerging for low-level descriptions of Web Services. DAML-S complements this effort by providing Web Service descriptions at the application layer, describing what a service can do, and not just how it does it. In this paper we describe three aspects of our ontology: the service profile, the process model, and the service grounding. The paper focuses on the grounding, which connects our ontology with low-level XML-based descriptions of Web Services.