Because this imposes unfair burdens on firms that attract lots of older or sicker people, reform is likely to include government-funded mechanisms for risk pooling or reinsurance.

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This partnership gives Allianz the opportunity get to know and make headway in the market while pooling risk.

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By pooling risk, Eurobonds could be a more durable counter to such destabilising liquidity crises, argues Paul De Grauwe, an economist at the Catholic University of Leuven, in Belgium.

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Rather than distributing risks, there was a pooling of risk in the largest financial institutions that made them very vulnerable and, because of their complex interconnections, very dangerous to the whole financial system.

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Caerphilly council said pooling budgets posed a "significant risk" as it could be considered to be subsidising its neighbour's services.

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Nissen, the New England Journal editors and statistician Sander Greenland at UCLA all make the argument that pooling all three studies is an appropriate way to identify risk.

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Many landlords may also decide that the best way to handle the extra risk that shorter leases entail is through a diversified portfolio ie, by pooling their risks with other landlords.

ECONOMIST: Commercial property