Weighting (Post-stratification)

Also known as: Post-stratification, Survey Weighting, Sample Balancing

Statistical adjustment of survey data to correct imbalances between sample composition and target population.

Weighting (or Post-stratification Weighting) is the statistical process of adjusting the weights of individual survey responses so that the final sample correctly reflects the distribution of the target population in key variables such as age, gender, socioeconomic level, and geographic region.

For example, if the collected sample is 60% women but the target population is 50/50, weighting gives more weight to men's responses and less to women's responses until the weighted distribution is 50/50.

Weighting improves result representativeness but has limits: if a subgroup is very underrepresented in the sample (e.g., only 5 men aged 65+ in a sample of 1000), weighting doesn't solve the underlying statistical problem.

Atlantia applies standard weighting in all its quantitative studies to guarantee representativeness.