Hello Albert,
The question (vote7: voted in last general election) may refer to the same general elections in more than one wave, so the same event is in multiple waves. The reason behind this is the length of the fieldwork in UKHLS - it takes about 30 months to complete one wave so it might happen that some people are interviewed before the GE and then are asked about this election in later waves, and the irregularity of the elections calendar in the recent years has further complicated the process.
Please have a look at our long-term content plan to see the rotations patterns around the General election (self-completion) module. https://www.understandingsociety.ac.uk/sites/default/files/downloads/general/long-term-content-plan.pdf
Here is the breakdown of GEs by UKHLS waves:
1) 6-May-10 is asked in wave 2
2) 07-May-15 – is in wave 7
3) 08-Jun-17 – is in waves 8, 9, 10
4) 12-Dec-19 - is in waves 11, 12
Here is the universe by wave, you can check them at: https://www.understandingsociety.ac.uk/documentation/mainstage/dataset-documentation/questionnaire-modules
• Wave 2: if month = 5 thru 12 (Sample month is May 2010 to December 2010)
• Wave 7: if month = 5 thru 12 (Sample month is May 2010 to December 2010)
• Wave 8: if (GRIDVARIABLES.ModeType = 1 & CASISTART.scac = 1 thru 3) | (GRIDVARIABLES.ModeType = 2|3) (Mode is face-to-face and has agreed to self-completion OR mode is telephone or web) and if DOI is after 8th June 2017 & (W8 sample months 8JE2 to 8DE2) (If interview is after the General Election in 2017 AND issued in sample months June to December wave 8 year 2)
• Wave 9: if (GRIDVARIABLES.ModeType = 1 & CASISTART.scac = 1 thru 3) | (GRIDVARIABLES.ModeType = 2|3) (Mode is face-to-face and has agreed to self-completion OR mode is telephone or web) and if DOI is after 8th June 2017 & (W9 sample months 9JE1 to 9MY2) (If interview is after the General Election in 2017 AND issued in sample months June year 1 to May year 2 Wave 9)
• Wave 10: if (GRIDVARIABLES.ModeType = 1 & CASISTART.scac = 1 thru 3) | (GRIDVARIABLES.ModeType = 2|3) (Mode is face-to-face and has agreed to self-completion OR mode is telephone or web) and if Wave 10 sample months 10JA1 to 10MY1 (If issued in sample months January Year 1 to May Year 1)
• Wave 11: if (GRIDVARIABLES.ModeType = 1 & CASISTART.scac = 1 thru 3) | (GRIDVARIABLES.ModeType = 2|3) (Mode is face-to-face and has agreed to self-completion OR mode is telephone or web) and if ff_snapelect = 1 (General election held prior to end of fixed-term parliament)
• Wave 12: if (GRIDVARIABLES.ModeType = 1 & CASISTART.scac = 1 thru 3) | (GRIDVARIABLES.ModeType = 2|3) (Mode is face-to-face and has agreed to self-completion OR mode is telephone or web) and if ff_snapelect = 1 (General election held prior to end of fixed-term parliament)
I hope this information is helpful.
Best wishes,
Roberto Cavazos
Understanding Society User Support Team
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