Partially Identified Prevalence Estimation under Misclassification using the Kappa Coefficient

We discuss a new strategy for prevalence estimation in the presence of misclassification. Our method is applicable when misclassification probabilities are unknown but independent replicate measurements are available. This yields the kappa coefficient, which indicates the agreement between the two measurements. From this information, a direct correction for misclassification is not feasible due to non-identifiability. However, it is possible to derive estimation intervals relying on the concept of partial identification. These intervals give interesting insights into possible bias due to misclassification. Furthermore, confidence intervals can be constructed. Our method is illustrated in several theoretical scenarios and in an example from oral health, where prevalence estimation of caries in children is the issue

Reden von »uns« und »ihnen« : eine soziologische Streitschrift von Frank-Olaf Radtke

Rezension zu: Frank-Olaf Radtke: Kulturen sprechen nicht. Die Politik grenzüberschreitender Dialoge. Hamburg 2011, Hamburger Edition, ISBN 978-3-86854-238-7, 151 Seiten, 12 Euro

Low-Complexity Energy-Efficient Broadcasting in One-Dimensional Wireless Networks

In this paper, we investigate the transmission range assignment for N wireless nodes located on a line (a linear wireless network) for broadcasting data from one specific node to all the nodes in the network with minimum energy. Our goal is to find a solution that has low complexity and yet performs close to optimal. We propose an algorithm for finding the optimal assignment (which results in the minimum energy consumption) with complexity O(N^2). An approximation algorithm with complexity O(N) is also proposed. It is shown that, for networks with uniformly distributed nodes, the linear-time approximate solution obtained by this algorithm on average performs practically identical to the optimal assignment. Both the optimal and the suboptimal algorithms require the full knowledge of the network topology and are thus centralized. We also propose a distributed algorithm of negligible complexity, i.e., with complexity O(1), which only requires the knowledge of the adjacent neighbors at each wireless node. Our simulations demonstrate that the distributed solution on average performs almost as good as the optimal one for networks with uniformly distributed nodes.Comment: 17 page

The Full ESWAN Destination-Based Approach: Operations And Evaluation

In response to the growing need to support better than best-effort (BE) quality of service (QoS) in mobile ad-hoc and sensor networks, many QoS models have been proposed. SWAN independent QoS model is introduced to operate on wireless ad-hoc networks. As a cross layer QoS model, SWAN is flexible and may run over any routing protocol or Media Access Control (MAC) layers. SWAN provides some advantages over competitive models However, SWAN is vulnerable to problems related to mobility and false admission. The original SWAN model discusses the two problems as part of a dynamic regulation of real-time flows, and introduced two solutions, namely source and network-based regulation algorithms. This paper criticizes both regulation algorithms and show why destination-based algorithm selects real-time victim flows in a better way. Then we provide test results to analyze and evaluate the destination-based approach

An interactive whiteboard for immersive telecollaboration

In this paper, we present CollaBoard, a collaboration system that gives a higher feeling of presence to the local auditory and to the persons on the remote site. By overlaying the remote life-sized video image atop the shared artifacts on the common whiteboard and by keeping the whiteboard's content editable at both sites, it creates a higher involvement of the remote partners into a collaborative teamwork. All deictic gestures of the remote user are shown in the right context with the shared artifacts on the common whiteboard and thus preserve their meaning. The paper describes the hardware setup, as well as the software implementation and the performed user studies with two identical interconnected system