Skip to content

2008 President · N2

Impact Research · fieldwork ended 2008-10-14 (21 days before the election) · 400 respondents · Live Phone · partisan sponsor (DEM)

The poll said

Democrat 44% · Republican 48%

R+4.0

The certified result

Democrat 49.97% · Republican 48.75%

D+1.2

The arithmetic

  1. Poll margin = 44 − 48 = -4.00
  2. Actual margin = 49.966 − 48.753 = 1.213
  3. Signed miss = -4.00 − (1.213) = -5.213
  4. Absolute miss = |-5.213| = 5.213

The poll overstated the Republican by 5.2 points and had the wrong leader.

Where these numbers come from

Poll and result: 538 raw_polls.csv. Poll ID 74501, race ID 8703 (538 database).