[A] Many now take issue with this view. Se

题目：

[A] Many now take issue with this view. Several economists reckon that the brain-drain hypothesis fails to account for the effects of remittances, for the beneficial effects of returning migrants, and for the possibility that being able to migrate to greener pastures induces people to get more education. Some argue that once these factors are taken into account, an exodus of highly skilled people could turn out to be a net benefit to the countries they leave. Recent studies of migration from countries as far apart as Ghana, Fiji, India and Romania have found support for this "brain gain" idea.

[B] There are more subtle ways in which the departure of some skilled people may aid poorer countries. Some emigrants would have been jobless had they stayed. Studies have found that unemployment rates among young people with college degrees in countries like Morocco and Tunisia are several multiples of those among the poorly educated, perhaps because graduates are more demanding. Migration may lead to a more productive pairing of people’s skills and jobs. Some of the benefits of this improved match then flow back to the migrant’s home country, most directly via remittances.

[C] The possibility of emigration may even have beneficial effects on those who choose to stay, by giving people in Door countries an incentive to invest in education. A study of Cape Verdeans finds that an increase of ten percentage points in young people’s perceived probability of emigrating raises the probability of their completing secondary school by around eight points.

[D] When people in rich countries worry about migration, they tend to think of low-paid incomers who compete for jobs as construction workers, dishwashers or farmhands. When people in developing countries worry about migration, they are usually concerned at the prospect of their best and brightest decamping to Silicon Valley or to hospitals and universities in the developed world. These are the kind of workers that countries like Britain, Canada and Australia try to attract by using immigration rules that privilege college graduates.

[E] The most obvious way in which migrants repay their homelands is through remittances. Workers from developing countries remitted a total of $325 billion in 2010, according to the World Bank. A skilled migrant may earn several multiples of what his income would have been had he stayed at home. A study of Romanian migrants to America found that the average emigrant earned almost $12,000 a year more in America than he would have done in his native land, a huge premium for someone from a country where income per person is around $7,500.

[F] Lots of studies have found that well-educated people from developing countries are particularly likely to emigrate. By some estimates, two-thirds-of highly educated Cape Verdeans live outside the country. This "brain drain" has long bothered policymakers in poor countries. They fear that it hurts their economies, depriving them of much-needed skilled workers who could have taught at their universities, worked in their hospitals and come up with clever new products for their factories to make.

[G] It is true that many skilled migrants have been educated and trained partly at the expense of their governments. Some argue that poor countries should therefore rethink how much they spend on higher education. But a new study of remittances sent home by Ghanaian migrants suggests that on average they transfer enough over their working lives to cover the amount spent on educating them several times over. The study finds that once remittances are taken into account, the cost of education would have to be 5.6 times the official figure to make it a losing proposition for Ghana.

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