TY  - CONF
T1  - The Opt-in Internet Panel: Survey Mode, Sampling Methodology and the Implications for Political Research
AU  - Hill, Seth
AU  - Lo, James
AU  - Vavreck, Lynn
AU  - Zaller, John
PY  - 2007
T2  - annual meeting of the Midwest Political Science Association
CY  - Chicago, IL
ER  -