CMU CASOS

The CASOS center at Carnegie Mellon University released new versions of their network analysis tools *ORA and Automap.

New features of *ORA include improved coordination between components, a Word  Cloud generator, improved support for foreign languages and Geospatial reporting.

The text mining tool Automap has an improved user interface and better text extracting capabilities.

Dominic  Johnson and James Fowler propose an evolutionary model of overconfidence, suggesting that overconfident populations in resource-rich environments are evolutionarily stable.

Paper abstract:

“Confidence is an essential ingredient of success in a wide range of domains including job performance, mental health, sports, business, and combat. Many authors have suggested that overconfidence–defined here as believing you are better than you are in reality–is advantageous because it serves to increase ambition, resolve, morale, persistence, and/or the bluffing of opponents. Read the rest of this entry »

Does the online collection of ego-centered network data reduce data quality? An experimental comparison

Elsevier’s Social Networks journal has published a corrected proof of a paper written by Uwe Matzat and Chris Snijders comparing the quality of ego-network data collected online vs. offline.

Elsevier

Paper abstract:

“We analyze whether differences in kind and quality of ego-centered network data are related to whether the data are collected online or offline. We report the results of two studies. In the first study respondents could choose between filling out ego-centered data through a web questionnaire and being probed about their network in a personalized interview. The second study used a design in which respondents were allocated at random to either online or offline data collection. Our results show that the data quality suffers from the online data collection and the findings indicate that this is the consequence of the respondents answering “mechanically”. We conclude that network researchers should avoid to simply copy traditional network items into a web questionnaire. More research is needed about how new design elements specific for web questionnaires can motivate respondents to fill out network questions properly.”

Entropy-Based Centralization and its Sampling Distribution in Directed Communication Networks

Informaworld

In the last  issue of Communication Monographs Frank Tutzauer and  Benjamin Elbirt propose a new measure of centralization for networks characterized by path-transfer processes.

From the authors:

“This article proposes a new measure of network centralization and reports the results of a simulation designed to determine the sampling distribution of the proposed measure.
The measure is based on the information-theoretic concept of entropy and is appropriate for those networks in which traffic flows over paths and propagates by means of transference.Tables of critical values are constructed which allow the researcher to conduct tests of significance.”

“The structure of the paper is as follows: First, the example networks used in this article will be described. Following an overview of some of the key developments in the centrality and centralization literature, including Borgatti’s (2005) taxonomy, pathtransfer processes will be modeled stochastically and the centrality measure appropriate for such processes will be reviewed. This actor-based measure of centrality will then be used to construct a network-based measure of centralization. Next, a simulation will be conducted that will allow the constuction of tables of critical values.  Finally, the critical-value tables will be applied to the illustrative networks and a few concluding thoughts will be offered.”