2009 House · NY-20
Siena College · fieldwork ended 2009-03-25 (6 days before the election) · 917 respondents · Live Phone
The poll said
Democrat 47% · Republican 43%
D+4.0
The certified result
Democrat 43.53% · Republican 42.62%
D+0.9
The arithmetic
- Poll margin = 47 − 43 = 4.00
- Actual margin = 43.528 − 42.620 = 0.908
- Signed miss = 4.00 − (0.908) = 3.092
- Absolute miss = |3.092| = 3.092
The poll overstated the Democrat by 3.1 points and had the right leader.
Where these numbers come from
Poll and result: 538 raw_polls.csv. Poll ID 64252, race ID 1804 (538 database).