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30 Years of economics for development

Frequently asked questions

Q: Why are there several estimates reported per country and year?

A: Unlike national accounts data, there is no agreed basis of definition for the construction of income/consumption distribution data. In general, one can not consider any source to be 'the official one'. Several sources report estimates based on different surveys, income/consumption concepts, population concepts, weighting procedures etc. Our task is only to report these estimates, to try to give as a precise documentation as possible and to evaluate the quality of the estimates.

Q: How do I know which estimate to choose if several ones are reported per country and year?

A: The answer depends upon the purpose of the study in which the data will be used, but in general we would suggest the following:

a) read the user guide to understand which set of underlying concepts we have defined as our preferred one and try to choose estimates according to that
b) make sure that the quality rating is the highest possible
c) if you use time series data for a country, strive to use data from the same source
d) read the country information sheets to understand if there are any special features in any of the sources

Please send your questions and observations to the database manager.

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