Skip to content

2018 House · MI-6

Change Research · fieldwork ended 2018-11-03 (3 days before the election) · 460 respondents · Text-to-Web/Online Ad · partisan sponsor (DEM)

The poll said

Democrat 42% · Republican 40%

D+2.0

The certified result

Democrat 45.69% · Republican 50.24%

R+4.6

The arithmetic

  1. Poll margin = 42 − 40 = 2.00
  2. Actual margin = 45.693 − 50.244 = -4.551
  3. Signed miss = 2.00 − (-4.551) = 6.551
  4. Absolute miss = |6.551| = 6.551

The poll overstated the Democrat by 6.6 points and had the wrong leader.

Where these numbers come from

Poll and result: 538 raw_polls.csv. Poll ID 56812, race ID 370 (538 database).