Skip to content

2018 House · MI-8

Change Research · fieldwork ended 2018-11-03 (3 days before the election) · 501 respondents · Text-to-Web/Online Ad · partisan sponsor (DEM)

The poll said

Democrat 47% · Republican 46%

D+1.0

The certified result

Democrat 50.61% · Republican 46.78%

D+3.8

The arithmetic

  1. Poll margin = 47 − 46 = 1.00
  2. Actual margin = 50.610 − 46.776 = 3.834
  3. Signed miss = 1.00 − (3.834) = -2.834
  4. Absolute miss = |-2.834| = 2.834

The poll overstated the Republican by 2.8 points and had the right leader.

Where these numbers come from

Poll and result: 538 raw_polls.csv. Poll ID 56812, race ID 372 (538 database).