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Spatial tree data are required for the development of spatially explicit models and for the estimation of summary statistics such as Ripley’s K function. Such data are rare and expensive to gather. This paper presents an efficient method of synthesizing spatial tree point patterns from nearest neighbour summary statistics (NNSS) sampled in small circular subwindows, which uses a stochastic optimization technique based on simulated annealing and conditional simulation. This nonparametric method was tested by comparing tree point patterns, reconstructed from sample data, with the original woodland patterns of three structurally different tree populations. Analysis and validation show that complex spatial woodland structures, including long-range tree interactions, can be successfully reconstructed from NNSS despite the limited range of the subwindows and statistics. The influence of the NNSS varies depending on the woodland under study. In some cases, the sampling results can be improved by reconstruction. Furthermore, it is clearly shown that it is possible to estimate second-order characteristics such as Ripley’s K function from small circular subwindows through the reconstruction technique. The results offer new opportunities for adding value to woodland surveys by making raw data available for further work such as growth projections, visualization, and modelling. [ABSTRACT FROM AUTHOR]

This paper uses survey information to examine several common assertions about the institutional prerequisites for successful profitability when a First Nation enters an economic enterprise either independently or in joint effort with an outside firm. In the winter of 2004–2005, we interviewed managers on both the First Nations and private sides of joint ventures and other business alliances in Canada, to determine what affected their recent profitability experience. We gathered information on the ages, sizes, and activities of the firms. We also gathered information about the firms’ management structures and relationship with the First Nation, and the characteristics of the government of the First Nation. With a sample size of 40 firms that responded, we found that several institutional characteristics affected profit positively: strong separation of management from band governance, participation in management planning, and the use of staggered terms in band council elections. We found that the likelihood of profitability decreased if the band had been in third party management as well as if there was formal participation of elders or hereditary chiefs in decision making. We offer interpretations of these results. Cet article utilise les données d’un sondage réalisé au cours de l’hiver 2004–2005 afin d’examiner plusieurs assertions courantes au sujet des préalables institutionnels requis pour atteindre la profitabilité des entreprises initiées par des Premières nations agissant seules ou en partenariat avec des acteurs privés. Nous avons interviewé des gestionnaires impliqués dans de tels partenariats d’affaires au Canada et provenant tant des Premières nations que du secteur privé. Nous voulions déterminer ce qui affectait la profitabilité qu’ils avaient connue récemment. Nous avons rassemblé de l’information sur l’âge, la taille et les activités des entreprises. Nous avons aussi recueilli des données sur la structure de gestion des entreprises, les relations avec les Premières nations et les caractéristiques de la gouvernance en vigueur dans les communautés d’accueil. Un échantillon, regroupant les quarante entreprises qui ont répondu, nous permet d’observer que plusieurs caractéristiques institutionnelles, comme la séparation claire entre la gestion des projets et la gouvernance des communautés, la participation dans la planification managériale et le recours à des mandats échelonnés lors des élections au conseil de bande, affectent positivement les profits. Nous avons aussi remarqué que les chances de profitabilité diminuent si les conseils de bandes jouent un rôle en tant que de tierce partie dans la gestion des entreprises et si les aînés ou les chefs héréditaires participent formellement au processus décisionnel. Nous tentons d’interpréter ces résultats. [ABSTRACT FROM AUTHOR]

Indices quantifying spatial forest structure are frequently used to monitor spatial aspects of tree attributes including biodiversity in research plots of limited size. The treatment of edge trees, which are close to the plot boundaries, can affect the estimation of such indices that include neighbour effects, since some of their neighbours are likely to fall outside the plot. This paper investigates whether and under what circumstances edge-correction methods are necessary and evaluates the performance of six different approaches: no edge correction, translation, reflection, buffer zone, and two new nearest-neighbour methods. The performance of edge-correction methods depends strongly on the algorithmic structure of the indices and the spatial pattern of tree positions involved. Some edge-correction methods introduce more error than ignoring edge bias altogether. For indices accounting for the diversity of tree positions and especially for those computing angles, translation or buffer zone methods reduce the estimation error regardless of the sample size. The use of the reflection method is associated with large bias values. One of the new nearest-neighbour edge-correction methods proves to be capable of reducing the bias considerably. The results confirm the need for sufficiently large monitoring plots to avoid bias from edge effects. Where this is impossible, neighbours beyond the plot boundary need to be included in the survey, thus providing unbiased estimates but at the cost of extra measurements. Sensitivity analysis is required for newly introduced indices prior to their first application. [ABSTRACT FROM AUTHOR]