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The paper aims to develop expressions for calculating the mutual impedance between isolated conductors buried in homogeneous earth. The conductors have finite length and arbitrary position.

The conductors are represented by the use of elementary electric dipoles. Well‐known existing expressions are employed for the electric field of these dipoles. The induced voltages are evaluated and the final expressions for the mutual impedance are derived. The resulting expressions involve infinite double integrals, evaluated by using adaptive quadratures that are, however, time consuming. Therefore, an alternative approach is followed involving Sommerfeld integrals (SI) for representing the electric field of a dipole and a recently devised method for computing the SI, in the spatial domain, by using calculation of discrete complex images.

Final expressions for parallel and perpendicular conductors were derived and numerical results for several values of frequency, conductors' length and horizontal distance between them, were produced. Comparison to results produced with the well‐known Pollaczek formula showed excellent agreement.

For future research, it is possible to use the developed expressions for earthing systems study, where the grounding grid is discretized and the moment method is invoked.

Currently, the formulas used for calculating mutual impedance are valid for parallel conductors of infinite length. With the present work, accurate expressions are given for finite length and arbitrary horizontal positioned conductors. In addition, the use of SI and the discrete complex image method results in a rapid and efficient tool for massive impedance calculations.

The purpose of this paper is to comprehensively review a large and heterogeneous body of academic literature on investors' feedback trading, one of the most popular trading patterns observed historically in financial markets. Specifically, the authors aim to synthesize the diverse theoretical approaches to feedback trading in order to provide a detailed discussion of its various determinants, and to systematically review the empirical literature across various asset classes to gauge whether their feedback trading entails discernible patterns and the determinants that motivate them.

Given the high degree of heterogeneity of both theoretical and empirical approaches, the authors adopt a semi-systematic type of approach to review the feedback trading literature, inspired by the RAMESES protocol for meta-narrative reviews. The final sample consists of 243 papers covering diverse asset classes, investor types and geographies.

The authors find feedback trading to be very widely observed over time and across markets internationally. Institutional investors engage in feedback trading in a herd-like manner, and most noticeably in small domestic stocks and emerging markets. Regulatory changes and financial crises affect the intensity of their feedback trades. Retail investors are mostly contrarian and underperform their institutional counterparts, while the latter's trades can be often motivated by market sentiment.

The authors provide a detailed overview of various possible theoretical determinants, both behavioural and non-behavioural, of feedback trading, as well as a comprehensive overview and synthesis of the empirical literature. The authors also propose a series of possible directions for future research.

The present paper is part of a study associated with the migration phenomenon and the formation of intercultural social and economic relations which emerged in Italy in the nineteenth century and its practical and social implications in the twenty‐first century. The city of Trieste, Italy consists of a case study which examines the formation of organizational networks in the Mediterranean and in Europe which consist of the basic body of the so called Greek commercial dispersion.

This study presents data collected from the analysis of archival documents. It is part of the scientific field of social anthropology and is a case study where participative observation was employed. Interviews with people offered the researchers ground to explain the purposes and reasons for the implementation of decisions related to the creation of the organizational networks.

The article discusses the relation between the national group with its unique cultural identity and entrepreneurship, emphasizing the cultural characteristics of such relation. The consequences from the existence of these networks in all sectors of the life of the community of these areas are investigated. To a third level of discussion, the mapping and analysis of the cultural interactions which emerged as a result of these networks shaping an integrated cultural identity is examined.

The project succeeds in making a theoretical and practical contribution to the way the development of organizational networks presented for Trieste, Italy can consist of a typical recourse for other areas of the Mediterranean where cultures and identities intermingle nowadays and migration and policy directions need to be implemented.

The authors apply topic sentiment analysis (several relatively new text analysis methods) to the study of public opinion as expressed in social media by comparing reactions to the Trayvon Martin controversy in spring 2012 by commenters on the partisan news websites the Huffington Post and Daily Caller.

Topic sentiment analysis is a text analysis method that estimates the polarity of sentiments across units of text within large text corpora (Lin & He, 2009; Mei, Ling, Wondra, Su, & Zhai, 2007).

We apply topic sentiment analysis to public opinion as expressed in social media by comparing reactions to the Trayvon Martin controversy in spring 2012 by commenters on the partisan news websites the Huffington Post and Daily Caller. Based on studies that depict contemporary news media as an “outrage industry” that incentivizes media personalities to be controversial and polarizing (Berry & Sobieraj, 2014), we predict that high-profile commentators will be more polarizing than other news personalities and topics.

Results of the topic sentiment analysis support this prediction and in so doing provide partial validation of the application of topic sentiment analysis to online opinion.

The purpose of this paper is to examine two novel theories that concern the relationship between stock market development (SMD) and foreign direct investment (FDI). The authors focus on Greece that was demoted to the emerging market category in 2013–2014 in the international lists.

This study is based on the period 1988–2014 that includes the sub-periods 1988–2001 (emerging market) and 2002–2014 (developed market). The authors adopt cointegration methods examining, on the one hand, if the relationship between SMD and FDI is positive or negative and, on the other hand, if it is long run or short run. The authors complete the analysis using the Markov Switching regression model for the test of robustness.

The results exhibit a weak positive and symmetric long-run relationship for the full period. In the first sub-period, the relationship is strong but in the second sub-period it is not significant. The results are confirmed by the Markov Switching regression model.

The precise definition of a theoretical framework that is tested by a compact empirical methodology leads to a novel suggested policy that will upgrade the Greek market to developed market as soon as possible.

This research aspires to contribute in the area of exploration of the psychological traits evolving by practitioners within the project management profession. Specifically, it investigates whether there is any difference in optimism levels among experienced project management practitioners and newcomers in the profession.

The research used the life orientation test-revised (LOTR) (Scheier et al., 1994) to calculate respondents’ optimism scores. With these scores at hand, the researchers could then apply inferential statistics in order to deduce any differences observed among optimism score and the respondents’ characteristics (age, years of experience etc.).

Based on the results of this research, several demographic variables were shown to be statistically significant with optimism. These were (1) the number of years of experience the respondent had in managing projects, (2) working in a government organisation and (3) possessing specific project management certifications, all of which were found to adversely affect the respondent’s optimism score.

This research was unique in applying a well-known psychological test instrument (LOTR) to provide insight into the psychological impacts of a career as an information technology (IT) project manager. It is also highly likely that this correlation between the length of time working as a project manager and the adverse impact on their optimism would also apply to not just IT project managers but all experienced project managers.