ANES Time Series studies 1948-1992 were released without respondent-level weights that adjust for nonresponse or within-household selection. Beginning in 1994, however, weights which provide these adjustments in combination with post-stratification (matching sample proportions to Current Population Study [CPS] estimates) have been included in Time Series study releases.
Weight variables used for the production of Guide Tables
Tables in the ANES Guide to Public Opinion and Electoral Behavior were produced from variables of the ANES Time Series Cumulative Data File. For select questions that have been administered comparably in 3 or more Time Series studies, the CDF combines data over time in cross-year variables.
Guide tables apply CDF weighting. In order to provide the best available estimates for each point in time, CDF cross-year weights represent optimal weighting available for each individual Time Series year. CDF data 1948-1992** are weighted to 1 (as they remain in the Time Series study releases for those years) but 1994-later data are weighted with the same nonresponse, within-household selection and post-stratification adjustments present in the release weights for these later Time Series studies.
Three weight variables from the CDF (VCF0009z, VCF0010z, VCF0011z) were used for production of Guide tables. The 3 weights are identical across all years except 1970. For 1970, each variable corresponds to one of 3 variable-level weights used in 1970 to select and weight respondents appropriately for the type of question -- 'Type 0,' 'Type 1,' or 'Type 2' (type '0' questions selected all respondents, weighted 1).
- VCF0009z applies when a CDF variable includes 1970 data from a type '0' variable
- VCF0010z applies when a CDF variable includes 1970 data from a type '1' variable.
- VCF0011z applies when a CDF variable includes 1970 data from a type '2' variable.
It should be noted that, for pre-post studies after 1994, variables VCF0009z,VCF0010z, and VCF0011z represent weighting from the the pre-election wave.
** (1970: type 0 vars)