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The dispersity of graphene oxide (GO) has an important effect on the properties of epoxy resin (EP) composites. Many modification and dispersion methods require the use of inert solvents which do not participate in the modification reaction, although GO can be uniformly dispersed in water and alcohol solvents. Based on this requirement, several inert solvents were selected as dispersion solvents to find out the suitable inert solvent for GO dispersion into EP matrix.

Several inert solvents with different solubility parameters were selected as dispersion solvents to prepare GO/EP composite. The microstructure, mechanical properties, insulation properties, dielectric properties and thermal property of the composite were characterized, which was due to find suitable inert solvent for GO dispersion into EP matrix.

The dispersity of N, N-dimethylformamide (DMF) was the best stable suspension state when it was used as solvent instead of occurring sedimentation and agglomeration. Moreover, DMF was further confirmed as a suitable inert solvent for the dispersion of GO into EP according to the mechanical properties, insulation properties and thermal conductivity characterization.

The dispersion of GO in solvents has already been researched, but the traditional solvents, such as alcohols and water, has shown their limitations with the increase of modification methods, which were not suitable for the modification environment such as cyanate graft modification. Therefore, it was very important to choose a kind of inert solvent for dissolving EP matrix and dispersing GO better.

Several inert solvents were used to disperse GO into EP, and the influence of different dispersing solvents on the adhesive was discussed through the analysis of the mechanical properties, insulation properties and thermal conductivity, which was due to explore the inert solvent suitable for GO dispersion.

The purpose of this study is to find the role of online informediaries on the perspective of price comparison and information aggregator. Specifically, the author wants to explain how the level of product involvement moderates the effect of price dispersion and product information quality on attitude toward product in online informediaries.

The data for this study are obtained from a three‐way factorial experimental research design. Data were collected from 258 college students who have an experience with an online informediary. Combining ANCOVA and regression analysis enables the study of attitude formation and yields encouraging results.

The study finds that high‐involvement consumers focus on systematic cues (e.g. product attributes) in evaluating product quality. However, when they feel that their initial search yields insufficient results, causing them to perceive more product performance risk, they search for additional cues (e.g. price dispersion). Low‐involvement consumers are mainly affected by price dispersion, which is a heuristic cue, and they evaluate the product more favorably under a high (vs low) level of price dispersion.

This paper is one of the first to consider and empirically test a heuristic‐systematic model for attitude toward product in online informediaries. It also uniquely tests the level of price dispersion to discern the important motivating factors.

To study the rheological behavior of aqueous dispersions of collagen gelled media and to bring it into relation with the gel stiffness and microstructure.

Collagen gelled media were prepared at different concentrations and their stiffness was measured with dynamic elastic modulus (DEM) technique. The gelled media were reduced into dispersions of micelles and gel liquid phase and the apparent viscosity of these systems was investigated as a function of the gap thickness, the shear rate and the collagen concentration. The gap thickness was varied between 20 and 200 μm. The microstructure of the broken gelled media was finally explored with optical microscopy.

DEM analysis has given values of the collagen gel stiffness ranging between 3 × 10⁻⁴ and 3.3 × 10⁻³ MPa. It has been shown that apparent viscosity grows with the increase of the gap thickness from 2 to 5 Pa s at constant collagen concentration and applied shear rate (4 percent, 100 s⁻¹). A rise in the collagen concentration has produced an increase in the apparent viscosity of gelled media dispersions. Nevertheless, the phenomenological law does not obey previously proposed equations but follows a sigmoid modal. Shear‐thinning phenomenon has been observed when the shear rate is varied between 10 and 2,000 s⁻¹.

The gel breaking process, which may cause changes in the microstructure of the micelles and hence in the rheological behavior of the dispersions, should be characterized measuring the forces acting on the samples during the rupture.

The paper provides useful information on the rheological behavior of aqueous dispersions of collagen gelled media.

Existing research concerning the impact of unions on relative wages provides evidence for the existence of significant union/non‐union wage differentials. However, union practices are deemed to have a more pervasive effect on the overall distribution of wages, reducing wage differentials across and within establishments. Attempts to explore union effects on wage dispersion in the context of the Italian labour market. Several indicators of wage dispersion are computed, using both industry and establishment level data, in the attempt to ascertain the different routes through which union presence affects the structure of wages. The empirical evidence shows that Italian trade unions have pursued “egalitarian” objectives and have succeeded in shaping pay policies which, through central and local negotiations, raise low wages and reduce wage differentials both among skill categories and across establishments.

The purpose of this paper is to understand different aspects of structural dispersion in virtual teams (VTs). The study measures five types of dispersion, their impact on VT performance and the moderating effect of electronic communication.

The authors collected data from 44 globally distributed VTs representing 403 members. The authors used details of the members’ locations to measure five elements of dispersion for each team: spatial, time-zone, number of locations, extent of numerical balance across locations and extent of isolated members for a team. The authors used two items to assess effective electronic communication and measured team performance on four items from three sources – members, leaders and third-party stakeholders.

Using regression, the authors found that the number of sites, degree of team balance and isolation had a negative impact on team performance. Spatial and temporal dispersion did not impact performance. Effective electronic communication moderated the relationship of team performance with team balance and the number of sites.

Study presents novel findings on the role of team configuration in VTs. Limitations: the study provides pointers to the likelihood of a non-linear relationship between spatial distance and performance; however, the scope of the paper does not permit an examination of this model. Future research can study this relationship. Second, the study does not examine how team configuration impacts the team processes that discount performance. Finally, the study treats each index of dispersion as independent of the others. The analysis does not study the interplay between and among the indices.

The findings provide clear indicators for managers and researchers of VTs on the issues associated with the location and configuration of the teams. Managers, while designing and managing dispersed members are now informed of the impact of the number of sites and the sub-group dynamics. The study underscores the importance of effective electronic communication in managing dispersion.

The study presents how faultiness based on location of VT sub-groups (as represented in the configuration of a team) can hamper performance. Literature suggests that this faultiness can also extend to social identities (based on gender, culture, etc.). The indicators provided by this study in this respect provide a topical focus for research because diverse dispersed teams are becoming more prevalent.

The study is the first empirical exploration of dispersion in VTs beyond the traditionally acknowledged dimensions of spatial distance and time-zones. It is a timely response to the recent trends in literature. Additionally, the study derives data from a unique data set of global VTs, thus making findings easily generalizable.

The purpose of this paper is to examine the impact of wage dispersion on sickness absenteeism observed in Belgian firms.

The authors use detailed linked employer-employee panel data for the period 1999-2006 that allow the authors to compute a conditional wage dispersion indicator following the Winter-Ebmer and Zweimüller (1999) methodology and to estimate the relationship between sickness absenteeism and wage dispersion while controlling for time-invariant workplace characteristics.

The authors find a positive and hump-shaped relationship between intra-firm wage dispersion and sickness absenteeism, the turning point of this relation being extremely high. In addition, the magnitude of the influence of wage dispersion on sickness absenteeism is found to be stronger in firms employing a larger share of blue-collar workers.

The results could therefore suggest that wage dispersion, suggestive of larger pay-for-performance mechanisms, decreases worker satisfaction and the workplace climate in general. Only a minority of workers, who are less sensitive to equity and cohesion considerations, would be less absent as pay-for-performance increases.

While numerous approaches analyse the link between wage dispersion and firm productivity, very few studies we are aware of are devoted to the relationship between wage dispersion and sickness absenteeism. Yet, the outcomes in terms of productivity and sickness absenteeism may be different. Furthermore, the influence of wage dispersion on sickness absenteeism does not seem unambiguous from a theoretical point of view. To the authors knowledge, it is the first time that this relation is analysed with Belgian data.

The purpose of this paper is to explore the scope of robust dispersion control charts in a distribution-free environment, which is a specific case of non-normal control charts. These control charts are skewness-based structures designed to monitor skewed-type processes whilst equally performing under symmetric processes. Moreover, the choice of a suitable control chart for a particular non-normal situation is also suggested.

The probability control limits approach is considered as an alternative way to determine the skewness-based structure of dispersion control charts. The proposals of five robust and two conventional Shewhart-type dispersion control charts are suggested as efficient competitors of skewness correction (SC) dispersion control charts. The evaluation of robust proposals and competing dispersion control charts is done through false alarm rate (FAR) and probability to signal (PTS) measures.

The proposed dispersion control charts are found robust and efficient alternatives of SC dispersion control charts in both normal and non-normal distributions. The FARs and PTS properties of proposed control charts are impressive in all studied cases, and a real-data example also verifies the dominance of proposed control charts.

Conventional dispersion control charts quickly lose their efficiency as underlying process distribution deviates from normality; however, robust control charts emerge as most suitable candidates in such situations. This paper proposes the idea of robust dispersion control charts under a distribution-free structure for the skewed-type process, which is not yet explored.

The purpose of this paper is to examine the impact of management’s choice of forecast precision on the subsequent dispersion and accuracy of analysts’ earnings forecasts.

Using a sample of 3,584 yearly management earnings per share (EPS) forecasts and 10,287 quarterly management EPS forecasts made during the period of 2002-2007 and collected from the First Call database, the authors controlled for factors previously found to impact analysts’ forecast accuracy and dispersion and investigate the link between management forecast precision and attributes of the analysts’ forecasts.

Results provide empirical evidence that managements’ disclosure precision has a statistically significant impact on both the dispersion and the accuracy of subsequent analysts’ forecasts. It was found that the dispersion in analysts’ forecasts is negatively related to the management forecast precision. In other words, a precise management forecast is associated with a smaller dispersion in the subsequent analysts’ forecasts. Evidence consistent with accuracy in subsequent analysts’ forecasts being positively associated with the precision in the management forecast was also found. When the present analysis focuses on range forecasts provided by management, it was found that lower precision (a larger range) is associated with a larger dispersion among analysts and larger forecast errors.

Evidence suggests a consistency in inferences across both annual and quarterly earnings forecasts by management. Accordingly, recent calls to eliminate earnings guidance through short-term quarterly management forecasts may have failed to consider the linkage between the attributes (precision) of those forecasts and the dispersion and accuracy in subsequent analysts’ forecasts.

This study contributes to the literature on both management earnings forecasts and analysts’ earnings forecasts. The results assist in policy deliberations related to calls to eliminate short-term management earnings guidance.

The purpose of this paper is to investigate the effects of corporate dispersion on tax avoidance from geographical and institutional dispersion perspectives by using evidence from China.

Using a panel data of Chinese listed firms during 2003-2015, this paper estimates with correlation analysis and multiple regression analysis.

Both geographical and institutional dispersion are negatively associated with the degree of corporate tax avoidance. Furthermore, corporate governance mechanisms and female chief executive officers can mitigate the negative relation between corporate dispersion and tax avoidance. The results also indicate that ineffective internal control is one of the channels through which corporate dispersion reduces tax avoidance.

This is the first paper about the impact of firm dispersion on the degree of tax avoidance, complementing the research content of diversification and corporate decision-making.

Financial analysts have been found to be overconfident. The purpose of this paper is to study the ramifications of that overconfidence on the dispersion of earnings estimates as a predictor of the US business cycle.

Whether aggregate analyst forecast dispersion contains information about turning points in business cycles, especially downturns, is examined by utilizing the analyst earnings forecast dispersion metric. The primary analysis derives from logit regression and Markov switching models. The analysis controls for sentiment (consumer confidence), output (industrial production), and financial indicators (stock returns and turnover). Analyst data come from Institutional Brokers Estimate System, while the economic data are available at the Federal Reserve Bank of St Louis Economic Data site.

A rise in the dispersion of analyst forecasts is a significant predictor of turning points in the US business cycle. Financial analyst uncertainty of earnings estimate contains crucial information about the risks of US business cycle turning points. The results are consistent with some analysts becoming overconfident during the expansion period and misjudging the precision of their information, thus over or under weighting various sources of information. This causes the disagreement among analysts measured as dispersion.

This is the first study to show that analyst forecast dispersion contributions valuable information to predictions of economic downturns. In addition, that dispersion can be attributed to analyst overconfidence.