On requirements for federated data integration as a compilation process

Data integration problems are commonly viewed as interoperability issues, where the burden of reaching a common ground for exchanging data is distributed across the peers involved in the process. While apparently an effective approach towards standardization and interoperability, it poses a constraint to data providers who, for a variety of reasons, require backwards compatibility with proprietary or non-standard mechanisms. Publishing a holistic data API is one such use case, where a single peer performs most of the integration work in a many-to-one scenario. Incidentally, this is also the base setting of software compilers, whose operational model is comprised of phases that perform analysis, linkage and assembly of source code and generation of intermediate code. There are several analogies with a data integration process, more so with data that live in the Semantic Web, but what requirements would a data provider need to satisfy, for an integrator to be able to query and transform its data effectively, with no further enforcements on the provider? With this paper, we inquire into what practices and essential prerequisites could turn this intuition into a concrete and exploitable vision, within Linked Data and beyond

An evolutionary advantage of cooperation

Cooperation is a persistent behavioral pattern of entities pooling and sharing resources. Its ubiquity in nature poses a conundrum. Whenever two entities cooperate, one must willingly relinquish something of value to the other. Why is this apparent altruism favored in evolution? Classical solutions assume a net fitness gain in a cooperative transaction which, through reciprocity or relatedness, finds its way back from recipient to donor. We seek the source of this fitness gain. Our analysis rests on the insight that evolutionary processes are typically multiplicative and noisy. Fluctuations have a net negative effect on the long-time growth rate of resources but no effect on the growth rate of their expectation value. This is an example of non-ergodicity. By reducing the amplitude of fluctuations, pooling and sharing increases the long-time growth rate for cooperating entities, meaning that cooperators outgrow similar non-cooperators. We identify this increase in growth rate as the net fitness gain, consistent with the concept of geometric mean fitness in the biological literature. This constitutes a fundamental mechanism for the evolution of cooperation. Its minimal assumptions make it a candidate explanation of cooperation in settings too simple for other fitness gains, such as emergent function and specialization, to be probable. One such example is the transition from single cells to early multicellular life.Comment: 16 pages, 2 figure

Prospects and Limits of Tourism-Led Growth: The International Evidence

We investigate the relationship between tourism specialization and economic growth. We deviate from previous studies - which have reported mixed evidence - by allowing the relationship to take a nonlinear form. We find that tourism specialization is associated with higher rates of economic growth at relatively low levels of specialization but eventually diminishing returns set in and tourism's contribution becomes minimal. The policy lesson is that there is promise for tourism-led growth in developing countries but other economic activities must also be developed in order to carry the economy forward once the potential of tourism-led growth has been exhausted.tourism, tourism specialization, economic growth

Prospects and Limits of Tourism-Led Growth: The International Evidence

We investigate the relationship between tourism specialization and economic growth. We deviate from previous studies - which have reported mixed evidence - by allowing the relationship to take a nonlinear form. We find that tourism specialization is associated with higher rates of economic growth at relatively low levels of specialization but eventually diminishing returns set in and tourism's contribution becomes minimal. The policy lesson is that there is promise for tourism-led growth in developing countries but other economic activities must also be developed in order to carry the economy forward once the potential of tourism-led growth has been exhausted.Forecasting, agricultural economics