For countries such as China that weaken their currencies to seek competitive advantage in global trade, there is a "distinction between the perception of the impact of a depreciation and the actual impact a depreciation can have", says Michele Ruta, one of the study's authors.
The reality today, he says, is that years of data show the impact is likely to be much less than it used to be.
There are a number of reasons for that. But the biggest, say Mr Ruta and his colleagues, is the advent of global supply chains over the past two decades and the reality that many products today are agglomerations of parts made in many different countries
The result is a much more complex calculus for many economies such as China's and products that have become necessities of modern life.
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Weaker currencies do still lower the cost and therefore raise the international competitiveness of many goods exports while increasing the cost of imports.
For something as simple as a bottle of Australian shiraz squeezed from grapes grown on Margaret River vines, that reality still holds and matters. A weak Australian dollar will lower the cost of an exported bottle and make it more attractive to offshore consumers. It will also increase the price of imports into Australia of French or Chilean rivals, providing another boost to the local industry.
But for more complex products, like many of the electronic items assembled in China, the real impact is far more difficult to calculate.
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In the case of a smartphone, for example, the screen may have been imported from Japan and the main chip from South Korea, while other parts are sourced in southeast Asia, Europe and even the US. So even as a weaker renminbi in theory lowers the price internationally of the finished product it also raises the cost of imported parts.
For that reason trade economists have increasingly begun to look at who gains the real "value-added" profits from products. Wherever you may buy an iPhone designed in California and assembled in China from parts from all over the world, most of the profits go to Apple not to Foxconn, the Taiwanese assembler or its workers in mainland China.
However, despite the shift in the global economy, in the case of China there is one reason why its exporters may gain more from a weaker currency than they once would have.
China's import intensity — how much of exports were made up of imported parts — has fallen dramatically in many categories over the past decade. China has been expanding its own homegrown supply chains, something trade economists have cited as one reason for slowing growth in global trade in recent years.