CBS News
Graded against the actual result across 6 races (from 22 polls, through 2016).
Every race (6)
Each race CBS News polled, scored on its final poll — the call right before the vote — against the actual Dem−Rep result. Click a race for its full detail.
| Race | Their call | Result | Miss | Call |
|---|---|---|---|---|
| 2016 US President | D+4.0 | D+2.2 | 1.8 | ✓ |
| 2012 US President | D+2.0 | D+3.9 | 1.9 | ✓ |
| 2008 US President | D+9.0 | D+7.4 | 1.6 | ✓ |
| 2004 US President | R+1.0 | R+2.4 | 1.4 | ✓ |
| 2002 SD Senate | R+3.0 | D+0.2 | 3.2 | ✗ |
| 2000 US President | D+1.0 | D+0.5 | 0.5 | ✓ |
Accuracy by time to election
Lower is better. Time to election runs right (election week) to left (~2 months out).
By the numbers
| Time to election | Polls | Avg miss | vs field | Called right |
|---|---|---|---|---|
| ≤1 wk | 9 | 3.02 | -1.26 | 78% |
| 3–6 wk | 10 | 3.19 | -2.55 | 70% |
vs field is this pollster's average miss minus all pollsters' at the same lead time — green beats the field, redtrails it. Our historical polls reach ~2 months out; earlier polling isn't in the record.
Track record by cycle — getting better?
| Year | Polls | Avg miss | Lean (house effect) |
|---|---|---|---|
| 2000 | 7 | 2.2 | R+0.2 |
| 2004 | 5 | 3.1 | R+1.4 |
| 2008 | 6 | 3.7 | D+2.3 |
Do we credit a pollster for fixing its bias? Each cycle, the model re-estimates every pollster's lean from all its earlier polls (walk-forward) and subtracts it before using the poll. We tested weighting recent cycles more — it doesn't help: a pollster's lean in one cycle barely predicts the next (correlation 0.28), so the swings above are mostly noise, and averaging over more history beats chasing the latest cycle. The all-time estimate we use came out within ~0.5% of the best option.