2010 Senate · PA
Muhlenberg College Institute of Public Opinion · fieldwork ended 2010-10-18 (15 days before the election) · 403 respondents · Live Phone
The poll said
Democrat 44% · Republican 41%
D+3.0
The certified result
Democrat 48.99% · Republican 51.01%
R+2.0
The arithmetic
- Poll margin = 44 − 41 = 3.00
- Actual margin = 48.992 − 51.008 = -2.016
- Signed miss = 3.00 − (-2.016) = 5.017
- Absolute miss = |5.017| = 5.017
The poll overstated the Democrat by 5.0 points and had the wrong leader.
Where these numbers come from
Poll and result: 538 raw_polls.csv. Poll ID 32607, race ID 1537 (538 database).