Skip to content

2018 House · IA-4

Change Research · fieldwork ended 2018-10-28 (9 days before the election) · 631 respondents · Text-to-Web/Online Ad

The poll said

Democrat 44% · Republican 45%

R+1.0

The certified result

Democrat 47.04% · Republican 50.37%

R+3.3

The arithmetic

  1. Poll margin = 44 − 45 = -1.00
  2. Actual margin = 47.037 − 50.368 = -3.331
  3. Signed miss = -1.00 − (-3.331) = 2.332
  4. Absolute miss = |2.332| = 2.332

The poll overstated the Democrat by 2.3 points and had the right leader.

Where these numbers come from

Poll and result: 538 raw_polls.csv. Poll ID 56535, race ID 300 (538 database).