Sampling method used by the Population Register Centre
When checking to verify statements of support submitted in paper form for a Finnish citizens’ initiative or for a European citizens’ initiative, the Population Register Centre uses random sampling. All statements of support submitted in paper form are put in random order and a sample is taken. The size of the sample depends on the number of statements. A 99 per cent confidence level is used in sampling. This is the highest possible level that can be achieved in random sampling,
A two per cent margin of error is used in sampling which is applied to the true error rate of the sample examined. This gives a confidence interval for the sample. The confidence interval is always interpreted favourably for the organiser of a citizens’ initiative so that a group based on the lowest per cent of the confidence interval is rejected from the total group of statements of support.
Example of the application of the sampling method in the Finnish citizens’ initiative
- The number of statements of support submitted in paper form is 50,000.
- The Population Register Centre chooses a random sample of these for checking. Checking indicates that 5 per cent of the random sample of statements of support are invalid.
- A 2 per cent margin of error is applied to the true error rate of 5 per cent achieved. This means that 3-7 per cent of the total 50,000 statements of support are invalid.
- The Population Register Centre complies with a favourable interpretation, which means that 3 per cent of the total initiatives statements of support are deemed as being invalid.
- Based on checking, the Population Register Centre certifies 48,500 of the statements of support and rejects 1,500. The conditions have thus not been met to submit the citizens’ initiative to the Parliament of Finland for consideration.
- If 52,000 statements of support had been submitted for checking, based on the factors above, the certified number of statements of support would have been 50,440, which would be a sufficient number to be submitted to the Parliament of Finland for consideration.