Simulation modelling of complex distribution systems

AbstractIn many lines of business distribution enterprises take over the burden of synchronization of the demand and supply aspects of the supply chain. Their part increases especially on very dynamic markets, with variable demand and a short product life cycle. Then one of the strategy is to postpone production and shift its last stage from the part of industrial companies to distributional enterprises. The article will discuss the issue of network configuration for the needs of complex realization of non-standard orders. The investigation has been conducted on the basis on enterprises designing interorganizational relations in networks of cooperating enterprises

The Flexibility and Specialization of Resources - Competitive Strategies of Materials Decoupling Points of a Network Supply Chain of Metallurgic Products

AbstractThe configuration of the supply chain which realizes the postponed production strategy, requires consideration of the issue of formation of network relations in order to increase the supply potential. The increase in the number of network relations shaped by materials decoupling point of the supply chain can be a consequence of an endeavour to reduce the logistic costs, improvement in the level of the customer service or an increase in innovativeness. In the model presented in the article the authors considered the issue of reducing logistic costs with the established high level of the customer service, taking into account the problem of the flexibility of resources

Managing the flow components in supply chains

Identification and evaluation of the frequency and the power of influence as well as effects of disruptions, are essential problems noticed both by practitioners and theoreticians of the management of flows in supply chains. They are a widely discussed problem of the resilience of the supply chain. This paper considers the strategy of strengthening the resilience by production postponement and constructing network relations with subcontractors and participants of distribution channels. The study took into account two locations of the material decoupling point in supply chains of metallurgic products. Due to the aim of the research, attention was focused on the material decoupling point of the supply chain: assembly to order

Social Networks in The Boardroom

This paper provides empirical evidence consistent with the facts that (1) social networks may strongly affect board composition and (2) social networks may be detrimental to corporate governance. Our empirical investigation relies on a large dataset on executives and outside directors of corporations listed on the Paris stock exchange over the 1992-2003 period. This data source is a matched employer employee dataset providing both detailed information on directors/CEOs and information on the firm employing them. We first find a very strong and robust correlation between the CEO's network and that of his directors. Networks of former high ranking civil servants are the most active in shaping board composition. Our identification strategy takes into account (1) firm and directors' fixed effects and (2) matching of firms and director along one observable and one unobservable characteristic. We then turn to real effects of such network activity. We find that firms where these networks are most active are less likely to change CEO when they underperform. This suggests that social networks in the board room impair corporate governance.

Does Entry Regulation Hinder Job Creation? Evidence from the French Retail Industry

Does entry regulation hinder job creation? We investigate this question in the context of the French retail industry, a sector that has experienced especially low rates of job creation over the last 25 years. Since the early 70s, the French government has required regional zoning board approval for the creation or extension of any large retail store. Using a unique database that provides time and regional variation in boards' approval decisions, we show that this requirement created barriers to entry in the retail sector. We also show that these barriers to entry, either measured directly by approval rates or predicted by the political composition of the boards, weakened employment growth in the retail industry. Our findings indicate that retail employment could have been more than 10% higher today had entry regulation not been introduced. Promoting product market competition may thus be a key reform for countries with poor employment performance.

When strong ties are strong Networks and youth labor market entry

The conditions under which young workers find their first real post-graduation jobs are both very important for the young’s future careers and insufficiently known given their public policy implications. To study these conditions, and in particular the role played by networks, we use a Swedish population-wide linked employer-employee data set of graduates from all levels of schooling which includes detailed information on family ties, neighborhoods, schools, and class composition over a period covering high as well as low unemployment years. We find that strong social ties (parents) are an important determinant of where young workers find their first job. This remarkably robust effect is estimated controlling for all confounding factors related to time, location, education, occupation, and the interaction of these. The effect is larger if the graduate’s position is “weak” (low education) or during high unemployment years, a pattern which does not emerge when analyzing the role of weak ties (neighbors or friends as measured using classmates and their parents). On the hiring side, by contrast, the effects are larger if the parent’s position is “strong” (e.g. by tenure or wage). We find no evidence of substitution in recruitment over time and fields induced by “family ties hires”. However, we do find that, just after their child is hired in their plant, parents experience a sharp drop in their wage growth. Overall, our results show that strong (family) ties are more important in the job finding process of young workers in weak positions than those weak ties usually measured in the literature (neighbors, in particular), suggesting that labor market experience and education are essential conditions for weak ties to be strong.Weak ties; social networks; youth employment

Teachers' Training, Class Size and Students' Outcomes: Learning from Administrative Forecasting Mistakes

This paper studies the impact of different teacher and class characteristics on third graders' outcomes. It uses a feature of the French system in which some novice teachers start their jobs before receiving any training. Three categories of teachers are included in the sample: experienced teachers, trained novice teachers and untrained novice teachers. To identify the effects, we use administrative mistakes in forecasting the number of teachers. We find that trained and untrained novice teachers are assigned to similar classes, whereas experienced teachers have better students located in better environments. Hence, in order to match similar students and classes, we focus on pupils with novice teachers and discard those with experienced teachers. In addition, we show that the same sample can be used to estimate the causal effect of class size on students' outcomes. Our findings are: (1) teachers' training substantially improves students' test scores in mathematics; (2) this training effect does not rely on different teaching practices, but mainly on subject matter competence; untrained teachers who majored in sciences at university improve their students' achievement as much as trained teachers do; (3) the class size effect is substantial and significant; class size does not seem to be correlated with instructional practices; (4) teachers' training does not improve the scores of initially low-achieving students and classes; on the contrary, a smaller class is more beneficial to low-achieving students within classes and to all students in low-achieving classes.teachers' training, class size