An Institutional Approach to Donor Control: From Dyadic Ties to a Field‐Level Analysis

Literature on the nonprofit sector focuses on charities and their interactions with clients or governmental agencies; donors are studied less often. Studies on philanthropy do examine donors but tend to focus on microlevel factors to explain their behavior. This study, in contrast, draws on institutional theory to show that macrolevel factors affect donor behavior. It also extends the institutional framework by examining the field‐level configurations in which donors and fundraisers are embedded. Employing the case of workplace charity, this new model highlights how the composition of the organizational field structures fundraisers and donors alike, shaping fundraisers’ strategies of solicitation and, therefore, the extent of donor control.

Living with Jesus: Practical Christologies in Two Boston American Baptist Churches

This dissertation, an exercise in practical theology, undertakes two tasks. First, it examines how the story of Jesus is appropriated and embodied in the corporate practices of worship and mission (congregational christology) and in the daily lives of ordinary believers (everyday christology) at First Baptist Church in Jamaica Plain and Ruggles Baptist Church in Boston, Massachusetts. Second, it places these practical christologies in dialogue with the academic christology of James McClendon to see what creative and critical insights emerge. A key assumption of the study is that doctrinal reflection is precipitated when the story of Jesus interacts with human stories in both autobiographical and public domains. "Living with Jesus" contends that the understandings of Jesus present in the everyday lives of believers and in a congregation's worship and mission merit the attention of scholars in the disciplines of sociology and theology. This dissertation demonstrates that scholarly research on the visible church, everyday religion, and Christian doctrine pays limited attention to the theologies operative in the everyday lives of believers and congregational practices. A gap exists in scholarly knowledge, which "Living with Jesus" attempts to redress. The empirical results of qualitative research fieldwork are set in the context of historical overviews and contemporary snapshots of First Baptist Church in Jamaica Plain and Ruggles Baptist Church. "Living with Jesus" identifies three types of practical christology operative across the two congregations in corporate practices and the everyday lives of individuals: evangelical christology; exemplarist christology; and prophetic christology. The empirical research shows that for a significant minority of people in the sample, the prevailing understanding of Jesus can best be described as a hybrid christology. By paying attention to McClendon's treatment of the Jesus story and placing the three identified practical christologies in dialogue with his christology, it becomes apparent that each practical christology is simultaneously liberating and limiting. This dissertation argues that evaluating a particular practical christology in relation to the Gospel requires an intentional and disciplined effort on the part of congregations, ordinary believers, and theologians. Questions are proposed to assist further christological reflection on worship, mission, pastoral care, and Christian education.

Detour-Based Mobility Coordination in DTNs

Commonly, research work in routing for delay tolerant networks (DTN) assumes that node encounters are predestined, in the sense that they are the result of unknown, exogenous processes that control the mobility of these nodes. In this paper, we argue that for many applications such an assumption is too restrictive: while the spatio-temporal coordinates of the start and end points of a node's journey are determined by exogenous processes, the specific path that a node may take in space-time, and hence the set of nodes it may encounter could be controlled in such a way so as to improve the performance of DTN routing. To that end, we consider a setting in which each mobile node is governed by a schedule consisting of a ist of locations that the node must visit at particular times. Typically, such schedules exhibit some level of slack, which could be leveraged for DTN message delivery purposes. We define the Mobility Coordination Problem (MCP) for DTNs as follows: Given a set of nodes, each with its own schedule, and a set of messages to be exchanged between these nodes, devise a set of node encounters that minimize message delivery delays while satisfying all node schedules. The MCP for DTNs is general enough that it allows us to model and evaluate some of the existing DTN schemes, including data mules and message ferries. In this paper, we show that MCP for DTNs is NP-hard and propose two detour-based approaches to solve the problem. The first (DMD) is a centralized heuristic that leverages knowledge of the message workload to suggest specific detours to optimize message delivery. The second (DNE) is a distributed heuristic that is oblivious to the message workload, and which selects detours so as to maximize node encounters. We evaluate the performance of these detour-based approaches using extensive simulations based on synthetic workloads as well as real schedules obtained from taxi logs in a major metropolitan area. Our evaluation shows that our centralized, workload-aware DMD approach yields the best performance, in terms of message delay and delivery success ratio, and that our distributed, workload-oblivious DNE approach yields favorable performance when compared to approaches that require the use of data mules and message ferries.

Seed Scheduling for Peer-to-Peer Networks

The initial phase in a content distribution (file sharing) scenario is a delicate phase due to the lack of global knowledge and the dynamics of the overlay. An unwise distribution of the pieces in this phase can cause delays in reaching steady state, thus increasing file download times. We devise a scheduling algorithm at the seed (source peer with full content), based on a proportional fair approach, and we implement it on a real file sharing client [1]. In dynamic overlays, our solution improves up to 25% the average downloading time of a standard protocol ala BitTorrent.