Session 5: Attrition, weighting and imputation

• Non-response is a very important issue in all surveys
  • more so in household surveys
  • more so in panels
• Several types:
  • Item non-response: missing values in variable
  • Individual refusal within household: household info incomplete
  • Loss of individuals over time: attrition
• Of these only attrition is special to panel studies, because of the longitudinal orientation
• But all affect the BHPS and all require remedies: weighting for attrition and imputation for item/individual non-response