Unfortunately, I think the Guardian article got a few things wrong.
1. The Guardian article links to accurate official statement that the Chinese spend more than half of their foreign aid in Africa but then disregards the official published Chinese statistics on aggregate official aid to Africa (which would be a total of about $26 billion up to 2012*) in favor of the overblown figure circulated by AidData ($80 billion between 2000 and 2012). The article strongly implies that the AidData figure is an official figure. It is not. It purports to include all finance from China (real and "under discussion" including commercial loans, export credits, and other trade-related finance). Further, despite some improvements, AidData still gets a lot of these figures wrong, as our SAIS-CARI spot check of their hydropower project data revealed. They over count, by a big margin.
2. This misunderstanding continues in this sentence: "Researchers took data that China published on its foreign assistance," and geo-coded it. Whoa, Nelly! China did not publish that data, it was AidData that collected it, mainly from media reports.
3. The Guardian article also said that African leaders are three times more likely to spend Chinese aid in areas where they have ethnic ties. The paper in question actually said that they found no evidence for this. Their purported finding was that all things being equal, Chinese finance is more likely to go to the region of birthplace of an African leader than to another given region.
Readers of this blog know that I have been critical of AidData in the past. This summer our team looked again at their data and found that it had been improved -- although they still have a large number of "false positives" (projects that AidData says have been promised finance, but where our investigations show that these projects were wishful thinking on the part of an African government or a Chinese contractor: many never secured finance). But -- perhaps because of their name -- they cannot stop describing their numbers as "Chinese aid" even when their own discussions suggest that much of what they are tracking is trade and investment finance, for generating business.
* In the 2011 White Paper, the Chinese total for all aid provided globally from the start of the aid program up to 2009 was $37.7 billion with the 2014 White Paper announcing another $14.4 billion between 2009 and 2012. Assuming the percentage going to Africa was about half, this would have been $26 billion.