Understanding differences in construction project governance between developed and developing countries

Whereas most experts recognize the substantial differences in the construction sector between developed and developing countries, very little is known about how and to what extent construction project governance actually differs between the two contexts. In order to shed light on these differences, a suitable definition of project governance must be adopted and identical variables must be assessed in developed and developing contexts. Three characteristics of temporary multi-organizations that conduct construction projects (used here as categories of analysis) help identify these differences: formal structuring, informal structuring, and the role and participation of stakeholders. Based on three case studies, a survey, and semi-directed interviews, significant differences are found in how power and authority are exercised (and leadership styles applied), in the use of informality and in the roles assumed by stakeholders. Although the analysis of such differences is often considered a diagnosis of problems to be ‘fixed’ in projects in developing countries, we believe that these differences should be read as project governance mechanisms of adaptation to different environmental conditions, and therefore key elements that need to be fully understood by professionals working in developing countries.     

Resource provision ego-networks in small Greek construction firms

The prominence of small professional service providers in a fragmented construction sector in part relates to the ability to provide competitive advantage through the provision of a personalized service in a context where diseconomies of scale prevail. The Greek construction industry is particularly representative of this trend towards the dominance of small businesses. The small business owner relies upon their ability to secure critical resources through personal networks which provide information, advice, funding and brokerage. Resource provision ego-networks are investigated structurally using social network analysis. A multiple case study approach is employed with comparative social network analysis, focusing on the density of ego-networks and the prominence of resource providers and associated subgroups. Findings show that commercial development activity is promoted through high-density networks, which infers that higher levels of connectivity characterize networks operating in environments of uncertainty. As these critical resource networks mature, they appear to rely less on strong ties and temporary formal project networks. Contractual relationships appear to co-exist with reciprocal flows of resources outside the contract's scope.

L'importance des petits prestataires de services professionnels dans un secteur du bâtiment qui est fragmenté tient pour partie à la capacité à assurer un avantage concurrentiel par la fourniture d'un service personnalisé dans un contexte où les déséconomies d'échelle prévalent. L'industrie grecque du bâtiment est particulièrement représentative de cette tendance à la dominance des petites entreprises. Le propriétaire d'une petite entreprise s'appuie sur sa capacité à garantir des ressources critiques par des réseaux personnels qui fournissent des informations, des conseils, du financement et des services de courtage. Les ego-réseaux prestataires de ressources sont examinés d'un point de vue structurel en utilisant une analyse des réseaux sociaux. Il est employé une approche basée sur une étude de cas multiples s'accompagnant d'une analyse comparative des réseaux sociaux, centrée sur la densité des ego-réseaux et sur l'importance des prestataires de ressources et des sous-groupes associés. Les résultats constatés montrent que la promotion des activités de développement commercial se fait par les réseaux haute densité, ce qui induit que des niveaux supérieurs de connectivité caractérisent les réseaux fonctionnant dans des contextes marqués par l'incertitude. Au fur et à mesure que ces réseaux de ressources critiques mûrissent, ils semblent moins s'appuyer sur des liens forts et des réseaux temporaires en rapport avec des projets formels. Il apparaît que les relations contractuelles coexistent avec des flux de ressources réciproques en dehors du champ du contrat.

ego-réseaux ou réseaux personnels, activité entrepreneuriale, réseaux prestataires de ressources, PME du bâtiment, analyse des réseaux sociaux     

Novel quantification of coupled natural and cross-sectoral water and nutrient/pollutant flows for environmental management

Human water use and anthropogenic water pollution and ecosystem deterioration have increased so much that it is now a strategic challenge to maximize benefits from various possible water uses, while ensuring that basic human needs are met and the environment is protected. We propose and develop a novel use of input-output flow analysis as a relatively simple, compact and powerful tool for quantification of coupled natural and cross-sectoral flows of water, nutrients, and pollutants in catchments. The tool quantifies implications of various environmental regulation and management scenarios for both natural water systems and engineered-economic systems and sectors that use and impact natural waters for meeting human needs. Specific case study application to water and nitrogen flows in the Swedish Norrstr?m drainage basin indicates considerable nitrogen load contributions to surface and coastal waters from slow groundwater flow paths and legacies of accumulated nitrogen in subsurface and immobile water pools. This implies that effective nitrogen load abatement cannot focus only on active sources but must also include downstream measures, which can capture and abate nitrogen/pollutant loading from different types of known and yet unknown point and diffuse sources within associated catchments.     

Belief change and its determinants in a regional setting

A modification of the Osgood-Tannenbaum sociopsychological model of belief change is applied to University of Cincinnati student perceptions of Southwest Ohio and of the Kentucky Bluegrass. Students scale their beliefs about the two regions; after a week, they are given a factual presentation associating the two regions and asked to again scale their beliefs. The variable which proves most important in the resultant belief changes for the Kentucky Bluegrass is the separation of the two regions on a student's initial belief scale, suggesting the willingness of the students to believe the new information. Further analysis indicates that although objective differences in the regions affect initial beliefs, they play a negligible role in the degree to which students change their beliefs. A “halo effect” is also discovered, in which beliefs not mentioned in the presentation change in predictable directions. The empirical results appear encouraging to recent efforts which have been made to change popular impressions about places.     

Evaluation of networks of randomized trials

Randomized trials may be designed and interpreted as single experiments or they may be seen in the context of other similar or relevant evidence. The amount and complexity of available randomized evidence vary for different topics. Systematic reviews may be useful in identifying gaps in the existing randomized evidence, pointing to discrepancies between trials, and planning future trials. A new, promising, but also very much debated extension of systematic reviews, mixed treatment comparison (MTC) meta-analysis, has become increasingly popular recently. MTC meta-analysis may have value in interpreting the available randomized evidence from networks of trials and can rank many different treatments, going beyond focusing on simple pairwise-comparisons. Nevertheless, the evaluation of networks also presents special challenges and caveats. In this article, we review the statistical methodology for MTC meta-analysis. We discuss the concept of inconsistency and methods that have been proposed to evaluate it as well as the methodological gaps that remain. We introduce the concepts of network geometry and asymmetry, and propose metrics for the evaluation of the asymmetry. Finally, we discuss the implications of inconsistency, network geometry and asymmetry in informing the planning of future trials.     

Inland subsurface water system role for coastal nitrogen load dynamics and abatement responses

We simulate and analyze long-term dynamics of coastal nitrogen (N) loading and the inland source changes and processes that may have determined its development over the past 60-year period and may govern its possible future responses to various N source management scenarios. With regard to processes, the results show that average basin-scale N delivery fractions to the coast may not be representative of the coastal impacts of either diffuse or point inland sources. The effects of inland source changes may be greatly redistributed in space-time and delayed by slow N transport and mass transfer processes in the subsurface water system of coastal catchments. Extrapolation of current N transport-attenuation conditions for quantification of future abatement effects may therefore be misleading if the extrapolation models do not realistically represent delayed long-term influences of slow subsurface processes. With regard to policy, the results show that and why national Swedish and international Baltic Sea region policies for coastal N load abatement may be difficult or impossible to achieve by inland source abatement only. Large mitigation of both point and diffuse sources may be necessary to achieve targeted coastal N load reductions fast and maintain them also in the long term.     

Uncertainty-accounting environmental policy and management of water systems

Environmental policies for water quality and ecosystem management do not commonly require explicit stochastic accounts of uncertainty and risk associated with the quantification and prediction of waterborne pollutant loads and abatement effects. In this study, we formulate and investigate a possible environmental policy that does require an explicit stochastic uncertainty account. We compare both the environmental and economic resource allocation performance of such an uncertainty-accounting environmental policy with that of deterministic, risk-prone and risk-averse environmental policies under a range of different hypothetical, yet still possible, scenarios. The comparison indicates that a stochastic uncertainty-accounting policy may perform better than deterministic policies over a range of different scenarios. Even in the absence of reliable site-specific data, reported literature values appear to be useful for such a stochastic account of uncertainty.     

A concentric morphology model for the detection of masses in mammography

We propose a technique for the automated detection of malignant masses in screening mammography. The technique is based on the presence of concentric layers surrounding a focal area with suspicious morphological characteristics and low relative incidence in the breast region. Mammographic locations with high concentration of concentric layers with progressively lower average intensity are considered suspicious deviations from normal parenchyma. The multiple concentric layers (MCLs) technique was trained and tested using the craniocaudal views of 270 mammographic cases with biopsy proven malignant masses from the digital database of screening mammography. One-half of the available cases were used for optimizing the parameters of the detection algorithm. The remaining cases were used for testing. During testing, malignant masses were detected with 92%, 88%, and 81% sensitivity at 5.4, 2.4, and 0.6 false positive marks per image. Testing on 82 normal screening mammograms showed a false positive rate of 5.0, 1.7, and 0.2 marks per image at the previously reported operating points. Furthermore, additional evaluation on 135 benign cases produced a significantly lower detection rate for benign masses (61.6%, 58.3%, and 43.7% at 5.1, 2.8, and 1.2 false positives per image, respectively). Overall, MCL is a promising computer-assisted detection strategy for screening mammograms to identify malignant masses while maintaining the detection rate of benign masses considerably lower.