The opinions of the general public are as important as those of the elite if a country wishes to achieve a comprehensive self-assessment process in terms of the African Peer Review Mechanism (APRM). But gathering and measuring the opinion of ordinary people is not a simple matter.

The author of this paper, Robert Mattes, Professor in the Department of Political Studies at the University of Cape Town, has immense experience in planning and conducting opinion surveys in Africa, notably in his role as co-founder of Afrobarometer. Here he warns against the traps and pitfalls awaiting the unwary.

The first of these traps is the belief that a more representative assessment of public opinion can be obtained by contacting an ever larger number of people. The law of diminishing returns comes into play, and the cost of increasing the sample size can outweigh the benefits. Professor Mattes argues that, while a representative survey is an irreplaceable element of the national self-review process, relatively small random probability samples of ordinary citizens can produce accurate and cost-effective results.

However, other elements must be in place to ensure the survey’s credibility. These include freedom to travel for fieldworkers; the availability of accurate census data; and the avoidance of inappropriate mechanisms, like polling heads of households instead of the people who reside in them.

He warns, too, that it is important to establish what can be learnt from ordinary citizens – and what is out of their domain.