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  1. Open source software (OSS), a form of Digital or Knowledge Commons, underlies much of the technology that we use in our daily lives. The existence and continuation of OSS relies on the contribution of private resources – personal time, volunteer energy, and effort of numerous actors (e.g., software developers’ time as a common-pool resource) – to public goods, the benefits of which are enjoyed by everyone. Nonprofit organizations such as the Apache Software Foundation (ASF) attempt to aid this process by providing various collective services to OSS projects, acting as a second-order actor in the production of the public good. To this end, the ASF Incubator has created policies – essentially rules or norms – that serve to protect its interests and, as they say, increase the sustainability of the projects. Each policy requires investment by ASF (in terms of money or the use of volunteer time) or an incubating project (in terms of taking project personnel time), the benefits of which can accrue to either party. Such policies may impose additional costs on incubating projects, leading to a decreased production of the OSS public good. Using the ASF Incubator policy documents, we construct a dataset that records who – ASF or an incubating project – bears the cost and who enjoys the benefit of each policy and procedure. We can code most policy statements as costing one party and benefiting one party. The distribution of costs and benefits according to party indicates whether the second-order actor is contributing to an increase in the public good and if they are doing so sustainably. Through a two-way ANOVA, we characterize the impact of ASF policies on the production of public goods (OSS). Being a part of ASF imposes some costs on projects, but these costs may make projects more sustainable. Our analysis shows that the distribution of costs and benefits is fairly symmetric between the ASF and incubating projects. Thus, the configuration of policies or the “institutional design” of the ASF could aid in producing the OSS public good by providing services that projects require. 
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  2. Abstract

    The Mado Megamullion is an oceanic core complex (OCC) in the Shikoku back‐arc basin within the Philippine Sea Plate. Mantle peridotites (serpentinized) recovered by six dredge and submersible cruises exhibit signatures of extensive deformation. Amorphous pseudomorphs after plagioclase in many of the samples, as well as plagioclase‐spinel intergrowths, are clear evidence of melt stagnation and mantle reaction. Spinels show a wide range of compositions in terms of their Cr#, Mg#, and TiO2content. The presence of apparently magmatic high‐temperature pargasitic amphibole in veins and as replacement of clinopyroxene suggests that it may be a primary or near‐primary mineral crystallized from a hydrous melt which is unusual for abyssal peridotites. Two trace‐element populations of clinopyroxenes are in equilibrium with depleted and enriched basaltic melts, respectively. Rare‐earth element (REE) in the most depleted clinopyroxenes are modeled by 10% fractional melting except for a ubiquitous La‐Ce “kick.” Multiple models of open system melting combined with subsequent mixing of an enriched melt can explain the REE data. Broadly it appears that the peridotites underwent variable degrees of partial melting with moderate influx of enriched melts, which agrees with the other textural and chemical evidence of melt‐rock reaction and re‐fertilization. The compositions of the accumulated melts simulated by the open system models reproduce the enrichments in fluid mobile elements (Ba, U, and Pb) observed in basalts dredged from the Shikoku basin. Back‐arc basin peridotites at Mado Megamullion appear to have a unique petrographic and geochemical character that is distinct from those of peridotites exposed at the seafloor after formation from mid‐ocean ridges.

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