Report
Gambling Survey for Great Britain - Year 2 (2024), wave 3 report: Official statistics
Gambling Survey for Great Britain - Year 2 (2024), wave 3 report
Weighting strategy
The data was weighted to take account of non-response, bias, and improve representativeness. As there was no disproportionate sampling, selection weights were not required. The weighting method consisted of 2 stages:
A logistic regression model for number of responses within a household (run for households with more than one eligible adult).
A calibration to population estimates.
For the first stage, forward and backward stepwise logistic regression models were used to test which variables were predictive of the number of responses within a household. These models were run only for households with more than one eligible adult. Area-level variables (from the 2021 census for England and Wales and the 2011 census for Scotland) and household-level variables were tested. Where both a household level and area level version of a given characteristic was available, the household-level version was used, for example, if household income and Index of Multiple Deprivation (IMD) were both predictive of the number of responses, only household income was used. The final regression model included all variables that were significant in the stepwise regressions these were; percentage of owner occupiers in the area, number of children in the household, household tenure, household income, population density, percentage of persons who are economically active in the area. Region of residence was also included in the model to control for any regional differences in survey response.
The predicted probabilities from this model were used to create response weights for households with more than one eligible adult. The weight was checked for outliers and left untrimmed. The weight for responding households with only one eligible adult was set to one.
The response weight was then calibrated to estimates of the eligible population, that is, residents of Great Britain aged 18 years and over. Calibration weighting adjusts the weight so that characteristics of the weighted achieved sample match population estimates, reducing bias. The following variables were included in the calibration: age categories by sex, region, IMD percentiles (quintiles for England and bitiles for Wales and Scotland), tenure, and ethnicity.
Estimates of the Great Britain population by age, sex, and region of residence were taken from Office for National Statistics (ONS) mid-year population estimates, which were for 2023 in the UK (Population estimates for the UK, England, Wales, Scotland and Northern Ireland - Office for National Statistics (opens in new tab).
Population estimates for IMD percentiles within each country were taken from ONS England and Wales (opens in new tab) and National Records of Scotland (opens in new tab). Population estimates for tenure and ethnicity were taken from the most recent Labour Force Survey (opens in new tab) data available, which was gathered between January and March 2024.
After calibration, the weight was checked for outliers and left untrimmed. The final weight for the 4,675 productive individuals has a design effect of 1.25, an effective sample size of 3,728, and efficiency of 81 percent.
Previous sectionGSGB Year 2 (2024), wave 3 report - Questionnaire completion times
Last updated: 14 April 2025
Show updates to this content
Data points within this report have been updated. For further information visit the notes section within Statistics on gambling participation – Year 1 (2023), wave 2: Official statistics.