The 2014 Debrief · post-mortem · permanent archive
How did the polling industry do this cycle?
The 2014 industry MAE landed at 4.8pt — graded across 479 historical races with a known outcome — and 225 polls were analyzed across 86 pollsters. Signed bias −3.06pt: pollsters again systematically over-predicted Democrats.
INDUSTRY MAE
4.8pt
vs midterm avg
SIGNED BIAS
−3.06pt
D-leaning
POLLS · POLLSTERS
225
86 firms
RACES SCORED
479
w/ known outcome
Industry mean absolute error · 2002–2014
Per-pollster scorecard · 2014 · sorted by MAE
Signed bias · ±5.3pt
MAE · 0–5.5pt
Biggest-miss races · 2014
| Race | Expected | Actual | Miss | Direction |
|---|---|---|---|---|
| us-governor-2014-oh | R+19.00 | R+30.61 | -11.6pt | R-margin underestimate |
| us-governor-2014-sd | R+36.00 | R+45.04 | -9.0pt | R-margin underestimate |
| us-governor-2014-ny | D+23.00 | D+15.13 | -7.9pt | D-margin overestimate |
| us-governor-2014-ks | D+3.50 | R+3.69 | -7.2pt | D-overestimate |
| us-governor-2014-ar | R+7.00 | R+13.95 | -7.0pt | R-margin underestimate |
| us-governor-2014-il | D+2.00 | R+3.92 | -5.9pt | D-overestimate |
| us-governor-2014-sc | R+9.00 | R+14.48 | -5.5pt | R-margin underestimate |
| us-governor-2014-md | D+1.50 | R+3.78 | -5.3pt | D-overestimate |