We revisit the influential work of Borjas (1995) on the economic gain to the host population from immigration-"the immigration surplus." We develop his analysis by using a general equilibrium endogenous growth model with endogenous capital and several sectors, including an R&D sector driving growth. Skilled immigration leads to a bigger R&D sector share resulting in higher long-term growth. If skilled labor and physical capital are complements, this growth gain increases. Growth effects on the immigration surplus dominate the purely static effects of Borjas, but are not sufficient to eliminate the emergence of losers (skilled natives) within the host population. Copyright Blackwell Publishing, Inc. 2007

Using a two-bloc endogenous growth model calibrated to two generic sending and receiving countries of equal size, we assess the growth and welfare impact of world migration flows of different skill compositions. The sending country (East) has a lower total factor productivity and a lower endowment of skilled labour. Migration can induce two growth-enhancing effects: an efficiency effect from the more efficient use of labour in the receiving country (West) and a sectoral reallocation effect from a fall in the host country skilled-unskilled wage rates. Despite growth gains there are both winners (migrants, the representative Western non-migrant household) and losers (the representative Eastern household remaining). Remittances can see the latter group joining the winners.JEL Classification: F22, F43, O41

The safety of patients is an important responsibility of health care providers, and significant compensation costs may arise if providers are negligent. A widely debated option involves liability for such compensation being placed with the hospital rather than the individual clinician, a system known as "enterprise liability". In the US, partial adoption of enterprise liability, and proposals for its universal introduction, have accompanied high profile "malpractice insurance crises" in the last two decades.Hospitals in England and Wales have been subject to this system since 1990, and risk pooling arrangements have emerged subsequently allowing hospitals to transfer their liability risk to an agency known as the NHS Litigation Authority. We explore some of the mechanisms used by this agency to provide hospital management with financial incentives to take care. We estimate the influence of these arrangements on the use of diagnostic imaging tests within hospitals, using a panel data set covering the period 2000-2004, during which period a policy shift took place leading to a form of "natural experiment". Our results suggest that the use of diagnostic tests did not respond to the incentives created during this period. We speculate that certain types of patient care activity, including the use of diagnostic tests, may be less responsive to incentives placed at the level of the hospital by comparison with incentives placed at the level of the clinician. Our findings may have implications for jurisdictions contemplating a move to enterprise liability, as well as wider implications for public sector organizations faced with financial incentives to improve service quality. DRAFT -DO NOT QUOTE

The UK, with its relatively liberal immigration policies following recent enlargements, has been one of the main recipients of migrants from new EU member states. What factors would contribute to immigration/emigration benefits/costs and economic growth driven by migration? Who are the winners and losers in both the sending and host regions? We utilize an endogenous growth two-bloc model with labour mobility of different skill compositions to address these questions. We show that migration, in general, is beneficial to the receiving country and increases the world growth rate. With remittances, the sending country in aggregate can also benefit. The only exception is in the case of unskilled migration, which can actually have a detrimental impact on the world growth rate. Winners are migrants, and the skill group in the region that sees its relative size decrease.JEL Classification: F22, F43, J24, J61, O41