2018 House · PA-1
The New York Times/Siena College · fieldwork ended 2018-10-28 (9 days before the election) · 502 respondents · Live Phone
The poll said
Democrat 45.98% · Republican 47.31%
R+1.3
The certified result
Democrat 48.74% · Republican 51.26%
R+2.5
The arithmetic
- Poll margin = 45.98 − 47.31 = -1.33
- Actual margin = 48.740 − 51.260 = -2.520
- Signed miss = -1.33 − (-2.520) = 1.189
- Absolute miss = |1.189| = 1.189
The poll overstated the Democrat by 1.2 points and had the right leader.
Where these numbers come from
Poll and result: 538 raw_polls.csv. Poll ID 56500, race ID 491 (538 database).