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Construction projects managers try their best for the project to go according to the plans. They always attempt to complete the projects on time and consistent with the predetermined budgets. Amid so many problems in project planning, the most critical and well-known problem is the Resource-Constrained Project Scheduling Problem (RCPSP). The purpose of this paper is to solve RCPSP using hybrid algorithm ICA/PSO.

Due to the existence of various forms for scheduling the problem and also the diversity of constraints and objective functions, myriad of research studies have been conducted in this realm of study. Since most of these problems are NP-hard ones, heuristic and meta-heuristic methods are used for solving these problems. In this research, a novel hybrid method which is composed of meta-heuristic methods of particle swarm optimization (PSO) and imperialist competitive algorithm (ICA) has been used to solve RCPSP. Finally, a railway project has been examined for RCPS Problem in a real-world situation.

According to the results of the case study, ICA/PSO algorithm has better results than ICAs and PSO individually.

ICA/PSO algorithm could be used for solving problems in a multi-mode situation of activities or considering more constraints on the resources, such as the existence of non-renewable resources and renewable. Based on the case study in construction project, ICA/PSO algorithm has a better solution than PSO and ICA.

In this study, by combining PSO and ICA algorithms and creating a new hybrid algorithm, better solutions have been achieved in RCPSP. In order to validate the method, standard problems available in PSPLib library were used.

Libraries need to develop information processing systems for evaluation, budgeting, planning, and operations. Electronic spreadsheets lend themselves to a variety of applications, but are time‐consuming to create. A model template and macros that can be used in many different types of library data analysis have been developed here. The procedures demonstrated here can build an essential set of tools for meeting fundamental goals of administrative efficiency, effective use of library resources, staff motivation, and rational policy making.

We augment a standard bilateral gift-exchange game to allow employees to communicate their gratitude for, or disapproval toward, the wage assigned to them by their manager. This provides employees with a means of reciprocation or emotion expression toward the employee which is not available in a standard gift-exchange game and may substitute for the higher-than-equilibrium efforts commonly seen in this environment. We find that employees express gratitude or disapproval according to the wage received, but these messages are not a substitute for monetary reciprocation as the relationship between wages and effort is unchanged. These results suggest that employees view the messages as a form of emotional expression independent from rewarding or punishing managers. Average wage levels are little affected by allowing messages, although wages do fall more over time in the absence of messages and individual managers’ wage choices are affected by the messages they receive.

This chapter analyzes the effects of introducing a graduated minimum wage in a model with optimal income taxation in which a government seeks to maximize social welfare. It shows that the optimal graduated minimum wage increases social welfare by increasing the low-productivity workers’ consumption and bringing it closer to the first-best. The chapter also describes how the graduated minimum wage in a social welfare optimum depends on important economy characteristics such as the government’s revenue needs, the social welfare weight of low-productivity workers, and the numbers and productivities of the different types of workers.

Working time accounts (WTAs) allow firms to smooth hours worked over time. The purpose of this paper is to analyze whether this increase in flexibility has also affected how firms adjust employment in Germany over the business cycle.

This paper uses rich microeconomic panel data and fixed effects estimations to compare the employment adjustment of firms with and without WTAs.

The authors show that firms with WTAs show a similar separation and hiring behavior in response to revenue changes as firms without WTAs. One possible explanation is that firms without WTAs used short-time work (STW) to adjust hours worked instead. However, the authors find that firms with WTAs use STW more than firms without WTAs.

These findings call into question the popular hypothesis that WTAs were the key driver of the unusually small increase in German unemployment in the Great Recession.

The purpose of this paper is to assess the change in the Italian and Spanish wage polarization degree in a time of economic crisis, taking into account the factors affecting labor force heterogeneity. Gender differences in the evolution of social fractures are considered by carrying out the analysis separately for males and females.

The approach by Palacios-Gonzánlez and García-Fernández (2012) on polarization is applied to the microdata provided by the EU Living Conditions Surveys (2007, 2010 and 2012). According to Palacios-Gonzánlez and García-Fernández’s approach, polarization is generated by two tendencies that contribute to the generation of social tension: the homogeneity or cohesion within group and the heterogeneity between groups. The following labor force characteristics are considered: gender, level of education, type of contract, occupational status and job status.

The results for Italy reveal a higher increase of polarization for women than for men from the perspective of the type of contract. In Spain, the wage polarization of women also increases more intensively compared to men from the perspectives of level of education, job status and occupational status, while in Italy the reduction of the wage polarization index by level of education can be related, above all, to an increase in overqualification of women.

While the empirical literature on polarization has made considerable investigation into employment and job polarization, this paper explores the rather less explored matter of wage polarization. Furthermore, particular attention is paid to the impact on polarization of the Great Recession.

The purpose of this paper is to show that entrepreneurship can be fruitfully analyzed by positing that entrepreneurs are searching for rates of return exceeding the risk-adjusted market rate of return, i.e., they try to create or discover economic rents.

A conceptual paper trying to bridge the gap between neoclassical economics and the entrepreneurship field by seeing entrepreneurship as the search for and creation of (entrepreneurial) rents.

In the short to medium term the search for and creation of entrepreneurial rents give rise to supernormal profits if successful. In the longer term these rents are dissipated and accrue to society at large as cheaper and better products. Entrepreneurial rents are crucial for bringing about the innovation and continuous structural change required to generate economic growth.

The search for entrepreneurial rents is crucial for economic development. Without the possibility to earn entrepreneurial rents, no entrepreneur would be willing to exercise entrepreneurship and exploit entrepreneurial opportunities. Successful entrepreneurship attracts imitating firms that push back profits to normal levels and the benefits of the innovation will be diffused to consumers.

Understanding the role of entrepreneurship and its compensation is crucial for analyses of potential policy measures. High ex post compensation for successful entrepreneurship cannot be taxed harshly without affecting entrepreneurs’ willingness to supply effort.

The entrepreneurial function and its compensation are often neglected in neoclassical economics. This is a major shortcoming, as the presence of and search for entrepreneurial rents are necessary for bringing about the innovation and structural change that result in economic growth.

The purpose of this paper is to estimate whether sexual activity is associated with wages, and also to estimate potential interactions between individuals’ characteristics, wages and sexual activity.

The central hypothesis behind this research is that sexual activity, alike health indicators and mental well-being, may be thought of as part of an individual’s set of productive traits that affect wages. Using two-stage estimations the author examines the relationship between adult sexual activity and wages.

The author estimates that there is a monotonic relationship between the frequency of sexual activity and wage returns, whilst the returns to sexual activity are higher for those between 26 and 50 years of age. In addition, heterosexuals’ sexual activity does not seem to provide higher or lower wage returns than that of homosexuals, but wages are higher for those health-impaired employees who are sexually active. Over-identification tests, robustness checks, falsification tests, as well as, decomposition analysis and sample selection modelling enhance study’s strength.

Contemporary social analysis suggests that health, cognitive and non-cognitive skills and personality are important factors that affect wage level. Sexual activity may also be of interest to social scientists, since sexual activity is considered to be a barometer for health, quality of life, well-being and happiness.

The paper adds to the literature on the importance of unobserved characteristics in determining labour market outcomes.

It is increasingly important to study labour market outcomes for people who are not in employment, education, or training (NEET). Where most studies focus solely on young people, the purpose of this paper is to include both younger and older NEETs to find out if there is any long-term scarring effect, and if the effect is different between these two groups.

This study uses a twin-based estimation method for the first time to measure the long-term effect of economic inactivity on income. The analysis is based on biological twins, in order to control for individuals’ unobservable heterogeneity. It is assumed that twins are similar to each other and the only unobservable heterogeneity is at the family level. Register-based data from Statistics Sweden is used.

The result indicates a significant negative income effect for those who have been in NEET, and is larger for those who have been in NEET for several consecutive periods of time. Individuals who were in NEET during 2001-2003 had on average 62 per cent lower income compared with their twin in 2011. The corresponding number for individuals who were in NEET for just one period was 33 per cent. Hence, time in NEET reduces income. The results show that the long-term scarring effect is not affected by age.

This study utilises for the first time a twin-based estimation method to measure the long-term effect of inactivity. Most studies focus solely on young people, but the authors also include an older group of people.