Giulio Ghellini

Estimating the Size of Street-Dwelling Populations Using Mark-Resighting Counts

Mark-resighting constitutes an advanced technology for estimating animal abundance. Joint hypergeometric maximum likelihood, Minta-Mangel and Bowden estimators are usually adopted with mark-resighting data. In presence of any tendency of animals to aggregate into groups, the Bowden estimator is the sole reliable method, providing that marks are quite evenly distributed among groups. In some cetacean surveys, marking disturbances are avoided through natural marking. Natural marking with Bowden criterion is used to estimate the abundance of street-dwelling populations. The marked individuals are persons identified and recorded in the initial part of the survey and recognizable in subsequent occasions. A simulation helps determine the performance of the Bowden estimator under a wide set of situations, taking into account key features of street-dwelling populations. When marked individuals are evenly distributed among groups, the strategy is efficient.

Labour Market Outcomes for Ph.D. Graduates

In the international framework a high presence of Ph.D. graduates in the labour market has often been identified as a key factor for innovation and for creating technological progress. The Ph.D. graduates are at the same time the most qualified people in terms of educational attainment and those who are trained and most inclined for research careers, therefore they are expected to contribute to the advancement and diffusion of knowledge and technologies. Recently a work at the OECD has raised a number of questions about their education-to-work transition, employment and mobility patterns [4] and one of the aim of the established organization of European Ph.D. students [9] was to improve working and studying conditions for young scientists in order to increase their commitment on European research and to improve the outcomes of European science. Consequentially in Europe it is becoming more and more frequent the adoption of well defined survey design on this population for monitoring their working careers. In spite of that, in Italy the information framework on training and working experience of Ph.D.s. seems to be quite inadequate and fragmented [20], even if Ph.D. studies have been introduced more than 20 years ago.