Testing the validity of social capital measures in the study of information and communication technologies

Social capital has been considered a cause and consequence of various uses of new information and communication technologies (ICTs). However, there is a growing divergence between how social capital is commonly measured in the study of ICTs and how it is measured in other fields. This departure raises questions about the validity of some of the most widely cited studies of social capital and ICTs. We compare the Internet Social Capital Scales (ISCS) developed by Williams [2006. On and off the ’net: scales for social capital in an online era. Journal of Computer-Mediated Communication, 11(2), 593–628. doi: 10.1111/j.1083-6101.2006.00029.x] – a series of psychometric scales commonly used to measure ‘social capital’ – to established, structural measures of social capital: name, position, and resource generators. Based on a survey of 880 undergraduate students (the population to which the ISCS has been most frequently administered), we find that, unlike structural measures, the ISCS does not distinguish between the distinct constructs of bonding and bridging social capital. The ISCS does not have convergent validity with structural measures of bonding or bridging social capital; it does not measure the same concept as structural measures. The ISCS conflates social capital with the related constructs of social support and attachment. The ISCS does not measure perceived or actual social capital. These findings raise concerns about the interpretations of existing studies of ‘social capital’ and ICTs that are based on the ISCS. Given the absence of measurement validity, we urge those studying social capital to abandon the ISCS in favor of alternative approaches.     

Risk Assessment of Human Listeriosis from Semisoft Cheeses Made from Raw Sheep's Milk in Lazio and Tuscany (Italy)

Semisoft cheese made from raw sheep's milk is traditionally and economically important in southern Europe. However, raw milk cheese is also a known vehicle of human listeriosis and contamination of sheep cheese with Listeria monocytogenes has been reported. In the present study, we have developed and applied a quantitative risk assessment model, based on available evidence and challenge testing, to estimate risk of invasive listeriosis due to consumption of an artisanal sheep cheese made with raw milk collected from a single flock in central Italy. In the model, contamination of milk may originate from the farm environment or from mastitic animals, with potential growth of the pathogen in bulk milk and during cheese ripening. Based on the 48‐day challenge test of a local semisoft raw sheep's milk cheese we found limited growth only during the initial phase of ripening (24 hours) and no growth or limited decline during the following ripening period. In our simulation, in the baseline scenario, 2.2% of cheese servings are estimated to have at least 1 colony forming unit (CFU) per gram. Of these, 15.1% would be above the current E.U. limit of 100 CFU/g (5.2% would exceed 1,000 CFU/g). Risk of invasive listeriosis per random serving is estimated in the 10^?12 range (mean) for healthy adults, and in the 10^?10 range (mean) for vulnerable populations. When small flocks (10–36 animals) are combined with the presence of a sheep with undetected subclinical mastitis, risk of listeriosis increases and such flocks may represent a public health risk.     

Mobilizing on Campus: Conservative Movements and Today’s College Students1

Social movement scholars have known for some time that students, and particularly college students, play an important role in modern social movements. Yet the full extent of conservative mobilizing, both today and in the past, is frequently overlooked. This article highlights the critical role college campuses have played in the rise of conservative movements in the United States over the last 40 years. In doing so, it develops a concept of transition points to help explain the mechanisms responsible for the longstanding finding that college students form an important core of many social movements. Transition points are marked by both changes in routines and changes in social network configuration. The utility of the transition point concept is explored through ethnographic and interview data from the American pro‐life movement.     

On credible coalitional deviations by prudent players

In this paper we first explore the predictive power of the solution notion called conservative stable standard of behaviour (CSSB), introduced by Greenberg (The theory of social situations, 1990), in environments with farsighted players (as modelled in Xue, Econ Theory 11:603–627, 1998) as intuitively it is quite nice. Unfortunately, we find that CSSB has a number of undesirable properties: most importantly, it makes vacuous predictions for most natural social environments. Therefore, we introduce an intuitive refinement of this solution which we call conservative stable weak predictor. In settings of proper voting games, we explore some existence properties of this new solution and also show that it may not be unique. However, unfortunately, this refinement may also lead to non-intuitive vacuous predictions.     

Final outcome probabilities for SIR epidemic model

Abstract

We consider an SIR stochastic epidemic model in which new infections occur at rate f(x, y), where x and y are, respectively, the number of susceptibles and infectives at the time of infection and f is a positive sequence of real functions. A simple explicit formula for the final size distribution is obtained. Some efficient recursive methods are proved for the exact calculation of this distribution. In addition, we give a Gaussian approximation for the final distribution using a diffusion process approximation.     

ISLAMIC MOBILIZATION:

This article examines the emergence and growth of the Muslim Brotherhood in Egypt from the 1930s through the 1950s. It begins by outlining and empirically evaluating possible explanations for the organization's growth based on (1) theories of political Islam and (2) the concept of political opportunity structure in social movement theory. An extension of these approaches is suggested based on data from organizational documents and declassified U.S. State Department files from the period. The successful mobilization of the Muslim Brotherhood was possible because of the way in which its Islamic message was tied to its organizational structure, activities, and strategies and the everyday lives of Egyptians. The analysis suggests that ideas are integrated into social movements in more ways than the concept of framing allows. It also expands our understanding of how organizations can arise in highly repressive environments.     

Regional Computable General Equilibrium models: A review

Computable General Equilibrium (CGE) models are very popular for analyzing a wide range of policy issues. CGE applications vary from estimating the welfare impact of tax reform and alternative energy policies to the effect of foreign trade reforms, labour markets and employment. CGE models are commonly developed at the country level; however, modified versions of CGE, so called Regional CGE (RCGE) models, can be used at subnational disaggregation to examine impacts studied at the national counterparts on a specific region. RCGE models have grown in popularity as an alternative to the Input-Output (I-O) models, which are regularly used for regional analysis. RCGE models can provide comprehensive information, which make them more desirable analytical models for many researchers. Yet, RCGE models have not yet become a “go-to” for governmental policy practitioners when they are developing regional public policies. This paper reviews the current state of regional CGE models, describes their features, contributions and limitations and surveys some applications of the main three classes of RCGE models: region-specific, bottom-up, and top-down models. This paper concludes that the applications of RCGE are quite variable and flexible, with a new and more complex type of application to be developed with the advancement of computation economics. The paper offers recommendations on the micro, meso and macro conditions that are necessary to increase policy practitioners’ utilization of RCGE models.