How reliable are Afrobarometer results?
Based on our scientific methods, including random selection of respondents, a sample size of 1 200 respondents can give a very good – but not perfect – indication of what all Zimbabweans think.
All survey research comes with a “margin of sampling error”.
With a population the size of Zimbabwe’s, the margin of sampling error for a sample with 1 200 randomly selected respondents is plus or minus 3% at a “95% confidence level”.
This means that we can be 95% confident that the results from our sample are within +/-3 percentage points of the results we would get if we interviewed every adult Zimbabwean.
So on the question about trust in the president, for example, there’s a 95% chance that if we interviewed every adult Zimbabwean, we would find that between 61% and 67% of Zimbabweans say they trust the president “somewhat” or “a lot,” and just a 5% chance that the true number is outside this range.
That’s not perfect – but it’s pretty good (and it is widely accepted survey research methodology).
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