• An Assessment of Validity in Small Business and Entrepreneurship Research

      Buelens, Marc; Bouckenooghe, Dave; De Clercq, Dirk; Willem, Annick (UGent, Fac. Economie & Bedrijfskunde, 2005)
    • An efficient hybrid search algorithm for various optimization problems

      Vanhoucke, Mario (2006)
      This paper describes a detailed study of a recursive search algorithm for different optimization problems. Although the algorithm has been originally developed for a project scheduling problem with financial objectives, we show that it can be extended to many other application areas and therefore, can serve as a sub-procedure for various optimization problems. The contribution of the paper is threefold. First, we present a hybrid recursive search procedure for the project scheduling problem with net present value maximization and compare it with state-of-the-art procedures by means of computational tests. Second, we show how the procedure can be adapted to two other application areas: project scheduling with work continuity minimization and the open pit mining problem. Last, we highlight some future research areas where this hybrid procedure might bring a promising contribution.
    • An electromagnetism meta-heuristic for the nurse scheduling problem

      Maenhout, Broos; Vanhoucke, Mario (Vlerick Business School, 2005)
      In this paper, we present a novel meta-heuristic technique for the nurse scheduling problem (NSP). This well-known scheduling problem assigns nurses to shifts per day taking both hard and soft constraints into account. The objective is to maximize the preferences of the nurses and to minimize the total penalty cost from violations of the soft constraints. The problem is known to be NP-hard. Due to its complexity and relevance, many algorithms have been developed to solve practical, and often case-specific versions of the NSP. The enormous amount of different constraints has led to an overwhelming amount of exact and meta-heuristic procedures, and hence comparison and state-of-the-art reporting of standard results seem to be a utopian idea. The contribution of this paper is twofold. First, we present a meta-heuristic procedure for the NSP based on the framework proposed by Birbil and Fang (2003). The Electromagnetic (EM) approach is based on the theory of physics, and simulates attraction and repulsion of sample points in order to move towards a promising solution. Second, we present computational experiments on a standard benchmark dataset, and solve problem instances under different assumptions. We show that our procedure performs consistently well under many different circumstances, and hence, can be considered as robust against case-specific constraints. Keywords: meta-heuristics, electromagnetism, nurse scheduling
    • An electromagnetism Meta-Heuristic for the Resource-Constrained Project Scheduling Problem

      Debels, Dieter; Vanhoucke, Mario (UGent, Fac. Economie & Bedrijfskunde, 2004)
    • An electromagnetism Meta-heuristic for the resource-constrained project scheduling problem

      Debels, Dieter; Vanhoucke, Mario (Vlerick Business School, 2005)
      Recently, a new heuristic algorithm for global optimization has been proposed by Birbil and Fang (2003), referred to as Electromagnetism (EM). This technique is based on the electromagnetism theory of physics, and simulates attraction and repulsion of sample points in order to move towards an optimal solution. In this paper, we have extended the EM methodology for combinatorial optimization problems. To that purpose, we use the EM framework for solving the well-known resource-constrained project scheduling problem (RCPSP) heuristically. We rely on problem-specific characteristics to adapt the original EM framework to the problem under study. We present computational experiments on a standard benchmark dataset, compare the results of the different modifications on the original EM framework with current state-of-the-art heuristics, and show that the procedure is capable of producing consistently good results for challenging instances of the resource-constrained project scheduling problem. We also give directions for future research in order to make the EM framework competitive with the current state-of-the-art heuristics. Keywords: electromagnetism, meta-heuristics, resource-constrained project scheduling
    • An empirical analysis of asset-backed securitization

      Vink, Dennis; Thibeault, André (2008)
    • An empirical examination of financial reporting lags among small firms

      Van Caneghem, Tom; Van Uytbergen, Steve; Luypaert, Mathieu
      This paper studies how the presence of cross-border as opposed to domestic venture capital investors is associated with the growth of portfolio companies. For this purpose, we use a longitudinal research design and track sales, total assets and payroll expenses in 761 European technology companies from the year of initial venture capital investment up to seven years thereafter. Findings demonstrate how companies initially backed by domestic venture capital investors exhibit higher growth in the short term compared to companies backed by cross-border investors. In the medium term, companies initially backed by cross-border venture capital investors exhibit higher growth compared to companies backed by domestic investors. Finally, companies that are initially funded by a syndicate comprising both domestic and cross-border venture capital investors exhibit the highest growth. Overall, this study provides a more fine-grained understanding of the role that domestic and cross-border venture capital investors can play as their portfolio companies grow and thereby require different resources or capabilities over time.
    • An exploratory study on principals' conceptions about their role as school leaders

      Bouckenooghe, Dave; Devos, Geert (2007)
      This inquiry, by means of the case study method, explored how the conceptions of principals about their role of school leader contribute to a better understanding of their behavior and the impact on school climate. The results showed that differences of how principals conceive their role as a leader affect indirectly through their leadership practices (i.e. initiating structure and supportive leadership), the unity in vision, collegial relations, collaboration, innovativeness and satisfaction of teachers. Based on a content analysis of interviews with 46 Belgian school leaders we distinguished three profiles: (1) the ‘people minded profile' with an emphasis on people, educational matters and thus on creating a professional teaching community, (2) the ‘administrative minded profile' with the focus on paperwork and the implementation of formal procedures and rules, and (3) the ‘moderate minded profile' with no explicit preference for people, educational or administrative matters. Drawing on three prototypical cases we described in depth that these types of principals often work under different school climate conditions. We relied on semi-structured interviews to gather data on principals' thoughts about their role as school leaders. Also, survey questionnaires were administered among 700 teachers in 46 schools to assess several features of school climate (i.e. goal orientedness, participation, formal and informal relationships, innovativeness), satisfaction of teachers, and leadership role behavior (i.e. initiating structure and supportive leadership behavior).
    • An inquiry on the relationship between self-other agreement on supervisor's transformational leadership and subordinates' assessment of supervisor's performance

      Ertürk, Alper; Verbrigghe, Jasmijn; Van den Broeck, Herman (2013)
      Given the importance of the extent to which supervisors and their subordinates agree in their assessment of supervisors' leadership, this study investigates the possible relationship between self-other agreement on supervisors' transformational leadership and subordinates' perceptions of supervisors' in-role and extra-role performance, through the mediating role of leader member exchange. Self-other agreement was conceptualized as the degree of congruence between supervisors' self-assessment and subordinates' assessment of supervisors' transformational leadership. Data were collected from 36 supervisors and 189 of their subordinates. Statistical analyses revealed that self-other agreement on vision and individual support are positively associated with subordinates' perception of leader member exchange, and in turn leader member fully mediates the relationship between self-other agreement and subordinates' perceptions regarding their supervisors' performance. Additionally, results from polynomial analyses indicate that subordinates' ratings of LMX would be higher for in-agreement/good and underestimator supervisors, and would be lower for in-agreement/poor and overestimator supervisors. Some managerial implications are also discussed.
    • Antecedents and consequences of performance management enactment by front line managers

      Dewettinck, Koen; Vroonen, Wim (Vlerick Business School, 2013)
    • Antecedents of task conflict in the entrepreneur-investor relationship: an effectuation perspective

      Appelhoff, Daniel; Mauer, René; Collewaert, Veroniek; Brettel, M. (2012)
      Survey data from 175 entrepreneurs confirm the theory of planned behavior as an appropriate
    • Are acquisitions worthwile? An empirical study of the post-acquisition performance of privately held Belgian companies involved in take-overs

      De Langhe, Tine; Ooghe, Hubert (Vlerick Business School, 2001)
      Few studies have addressed the performance of smaller unquoted companies involved in take-overs, especially in the Continental European countries. Therefore this study addresses the post-take-over financial characteristics of privately held companies involved in 143 Belgian take-overs between 1992 and 1994. Specifically, this paper examines the financial performance of the acquiring firm after the take-over, using statistical analysis of industry-adjusted variables. Our findings show that following the take-over, the profitability, the solvency and the liquidity of most of the combined companies decline. This decline is also reflected in the failure prediction scores. With respect to the added value, take-overs are found to be accompanied by increases in the labour productivity, caused by the general improvement of gross added value per employee of Belgian companies in the last ten years and partly caused by laying off the target's workers. So it seems that, contrary to the general expectations and beliefs, take-overs usually do not seem to improve the acquirer's financial performance.
    • Are biotech investments different? The perspective of the Venture Capitalist

      Manigart, Sophie; Baeyens, Katleen; Vanacker, Tom (Vlaamse Overheid - Dep. EWI, 2004)