Benchmark Report for the 2008 American National Election S…

Benchmark Report for the 2008 American National Election Studies Time Series and Panel Study ANES Technical Report Series, no. NES012493 Summary This report compares estimates from the 2008 ANES studies to authoritative population statistics to reveal accuracies and inaccuracies in weighted, post-stratified ANES estimates. The report examines descriptive statistics for November 2008. With poststratification weights, the Time Series data estimate 84 percent (36 of 43) of population proportions examined here accurately to within 5 percentage points or less of the corresponding benchmark, including presidential vote choice and many demographic characteristics. The Time Series data over-estimate voter turnout by 15 points and miss population benchmarks by more than 5 percentage points for the percentage of the population identifying as white, homeowners, home renters, the percentage of people living in a one-person household, and the percentage of people living in households with incomes of $14,999 or less or $100,000 or more. Excluding turnout, the average absolute error across all proportions examined was 1.9 percentage points. The internet Panel Study cross-sectional estimates (with poststratification weights) are accurate within 5 points of the benchmark for 84 percent of statistics examined (36 of 43). The Panel Study over-estimates voter turnout by 22 points and also differs from benchmarks by more than 5 points for the ...