Skip to content

2018 Governor · SD

Mason-Dixon Polling & Strategy · fieldwork ended 2018-10-20 (17 days before the election) · 500 respondents · Live Phone

The poll said

Democrat 45% · Republican 45%

even

The certified result

Democrat 47.60% · Republican 50.97%

R+3.4

The arithmetic

  1. Poll margin = 45 − 45 = 0.00
  2. Actual margin = 47.597 − 50.974 = -3.377
  3. Signed miss = 0.00 − (-3.377) = 3.378
  4. Absolute miss = |3.378| = 3.378

The poll overstated the Democrat by 3.4 points and showed a tie.

Where these numbers come from

Poll and result: 538 raw_polls.csv. Poll ID 56431, race ID 161 (538 database).