31 research outputs found
The returns to vocational education in Italy
Several studies promote vocational education as an effective solution to the school-to-work transition issues, which have become endemic for the most advanced economies. However, individuals choosing this track may face a trade-off among a labour-market advantage at early stage of their individual careers and quicker skills’ depreciation in the long-run, due to less adaptability and technological change, becoming less competitive than skills provided by academic-based education, in a lifelong learning perspective. Using microdata from the Survey of Household Income and Consumption (SHIW), we follow individuals over their life-cycle for at least 40 years, to investigate whether this view has empirical support in a borderline country-level labour market, stressing outcomes’ differences among school-based vocational education and a more traditional academic-based education at upper-secondary school level. We find strong and robust support to this trade-off,
evidencing how a critical labour-market shock as the 2007–08 Financial Crisis has diluted the early advantage of vocational skills. We further address for selectivity in education investigating whether outcomes may vary between cohorts from different decades. Whilst differences in youth employment appears in contrast among birth cohorts, there are no significant results for wages, but it seems clear that vocational skills have weakened moving through years
EFFECTS OF FIRE AND HERBIVORY ON THE STABILITY OF SAVANNA ECOSYSTEMS
Savanna ecosystems are characterized by the co-occurrence of trees and grass-es. In this paper, we argue that the balance between trees and grasses is, to a large extent, determined by the indirect interactive effects of herbivory and fire. These effects are based on the positive feedback between fuel load (grass biomass) and fire intensity. An increase in the level of grazing leads to reduced fuel load, which makes fire less intense and, thus, less damaging to trees and, consequently, results in an increase in woody vegetation. The system then switches from a state with trees and grasses to a state with solely trees. Similarly, browsers may enhance the effect of fire on trees because they reduce woody biomass, thus indirectly stimulating grass growth. This consequent increase in fuel load results in more intense fire and increased decline of biomass. The system then switches from a state with solely trees to a state with trees and grasses. We maintain that the interaction between fire and herbivory provides a mechanistic explanation for observed discontinuous changes in woody and grass biomass. This is an alternative for the soil degradation mechanism, in which there is a positive feedback between the amount of grass biomass and the amount of water that infiltrates into the soil. The soil degradation mechanism predicts no discontinuous chang-es, such as bush encroachment, on sandy soils. Such changes, however, are frequently ob-served. Therefore, the interactive effects of fire and herbivory provide a more plausible explanation for the occurrence of discontinuous changes in savanna ecosystems