Confidence interval

All figures in CIM reach studies are based on a sample, and therefore inevitably have a margin of error. For this reason, CIM fact sheets traditionally report the margin of error or the 95% confidence interval for the metrics being described. There is a 95% chance that the true value in the population lies between the minimum and maximum of the 95% confidence interval. Nothing prevents the user, taking into account the sample size, from calculating this confidence interval for other reach indicators provided by CIM (the calculation method is included in the appendix of the methodology of the Press Study).