This study offers an in-depth analysis of four rumors that spread through Twitter after the 2013 Boston Marathon Bombings. Through qualitative and visual analysis, we describe each rumor's origins, changes over time, and relationships between different types of rumoring behavior. We identify several quantitative measures-including temporal progression, domain diversity, lexical diversity and geolocation features-that constitute a multi-dimensional signature for each rumor, and provide evidence supporting the existence of different rumor types. Ultimately these signatures enhance our understanding of how different kinds of rumors propagate online during crisis events. In constructing these signatures, this research demonstrates and documents an emerging method for deeply and recursively integrating qualitative and quantitative methods for analysis of social media trace data.

Shared mental models (SMMs) provide an approach to improving team learning and performance. SMM means that team members share common expectations about the team processes, results, !and individual roles in achieving the team's objective. Our model of antecedents and consequences of SMMs demonstrates how cognitive capabilities contribute to effective software development teams. Higher scores on two meta-level cognitive skills (A-shaped skills and T-shaped skills) and a personality characteristic (agreeableness), which help teammates coordinate their skills and knowledge, enhance the development of an SMM and thereby enhance team performance. The results open new and important areas for research into both the meta-level cognitive skills and the agreeable characteristic required for team effectiveness. There is also promise for new approaches to team building.

Knowledge management systems (KMSs) have been criticized as having a North American bias. The cultural dimension of KMSs, particularly the relationship of learning and culture in KM projects, are rarely discussed. This paper addresses these concerns in a review of the conceptual foundations for KM and by examining implementations of KM projects. Despite the evolutionary changes in how KM is viewed, KMSs, as they have been designed, implemented, and reported, do not appear to provide for cultural diversity among users. Instead, the reports of KMSs indicate that such systems seek to create and maintain a homogeneous organizational culture, and the adoption of such a shared culture appears to be a prerequisite for success. The paper discusses KMSs as systems that exhibit boundary spanning objects and processes in three different categories, and an analysis of reported projects reveals that boundary spanning across national and ethnic boundaries is rare.

article Free Access Share on Remarks on “The Digital Approximation of Contours” Authors: Robert M. Mason View Profile , R. E. Cordray View Profile Authors Info & Claims Journal of the ACMVolume 4Issue 4Oct. 1957 pp 524–529https://doi.org/10.1145/320893.320909Published:01 October 1957Publication History 1citation260DownloadsMetricsTotal Citations1Total Downloads260Last 12 Months3Last 6 weeks1 Get Citation AlertsNew Citation Alert added!This alert has been successfully added and will be sent to:You will be notified whenever a record that you have chosen has been cited.To manage your alert preferences, click on the button below.Manage my Alerts New Citation Alert!Please log in to your account Save to BinderSave to BinderCreate a New BinderNameCancelCreateExport CitationPublisher SiteeReaderPDF

Introduction.Information about the spacing and orientation of atoms and molecules in a crystal is often related pictorially by means of contour maps.Bowden [1] cites a method, similar to that of Booth and Booth [2], for having computers print a field of numbers depicting levels of the electron density distribution as a function of two variables.The output typewriter is caused to associate a different character with each level and if sufficiently flexible in format it is also made to suppress zeros.Figure 1 shows such a representation.The map is then hand drawn by smoothly outlining groups of like characters on the answer sheet.Gerberich [3] describes, in a different connection, a method wherein the machine retains a complete number field in its memory until it has found all pairs of consecutive meshpoints valued on opposite sides of the contour lines.Then it prints out linearly interpolated coordinates defining the map.This approach is well adapted to problems in which high-speed storage is not at a premium.This paper reports on experiments in computing contours conducted on the NAREC, a high-speed digital computer at the Naval Research Laboratory.The distinguishing feature of the method is that the functional values are not computed over the whole two-dimensional field, but rather over a small number of one-dimensional contours.An iterative process is used to select the next meshpoint at which to evaluate the function.In principle, the function exists apart from any specific path connecting meshpoints.But here only those paths are followed which lie adjacent to predesignated contour lines.The determination of which point to evaluate next is based uponwhether the last functional value computed was above or below the particular density level specified.Thus, the immediately preceding values of the function become a part of the iterative process and influence the direction in which the machine charts the contours. Application of the method to a simple contour.To illustrate the method in detail, Figure 2 shows the path that the machine might follow in tracing the outer contour of Figure 1 over a coarse grid.The computation begins at a meshpoint, (x,y).By comparing several functional values in this vicinity with the specified contour level, k, the machine first determines the direction of steepest descent (ascent) to the equivalue line.Proceeding in this direction, say the y-direction, a sequence of values f(x, y + nay); n = 1, 2, 3, • • • is computed.At each new point the algebraic sign of the quantity f --kis ascertained.When a change in sign is detected, the machine has just crossed the contour line.The coordinates of the last inside point are recorded and saved for comparison later to signal the completion of a closed contour.Once a contour has been found, two rules governing changes in the scanning direction are brought into play to prevent losing it; namely, I.The path turns clockwise ninety degrees at each outside point.