Norway: Polling institutes at a glance

The PolitPro Score evaluates the reliability of polling institutes based on their accuracy in elections and neutrality toward political parties. Significant biases in favor of or against parties compared to election trends result in deductions. The maximum score is 100.

The accuracy indicates how closely pre-election polls matched the actual election results.

We compare pre-election polls from the institutes with the actual election results. This involves calculating the average deviation of party values and deriving an overall average. All parties with an election result of 3% or higher are included in the calculation.

Election polls typically have a margin of error of 2-3 percentage points. Average deviations of up to one percentage point are rated as very good (green), up to two percentage points as good (yellow). Deviations of up to three percentage points are rated as okay (orange) but may already show significant outliers for some parties. Average deviations exceeding three percentage points indicate issues with accuracy and reliability and are rated as poor (red).

The deviation measures how often an institute’s values significantly differ from the election trend. Frequent deviations for individual parties may indicate favoritism or disadvantage.

We calculate an institute’s deviation based on the values assigned to individual parties in election polls. To do this, we compare each party’s value with the PolitPro election trend, which calculates a weighted average from current polls. If a party’s value is within +/-1 percentage point of the election trend, it is rated as equal. If it is lower, it is rated as lower, and if higher, it is rated as higher.

From all surveys, we calculate how often an institute rates a party higher or lower (see the overview on the institute subpages). Deviations of up to 20% are considered normal. We sum all deviations above 20% for each institute. Example: If an institute rates a party higher than the election trend in 30% of cases, 10 points are added to the deviation score.

Based on this total score, we evaluate the deviation: A score of 0 is rated as "very low" (dark green). Scores between 1-30 are rated as "low" (light green). Scores from 31-60 show significant deviations from the election trend and are rated as "medium." Institutes with a total score of 61 or higher show clear deviations for one or more parties and are accordingly rated as "high" (orange).

Note: We recommend evaluating deviation in combination with election accuracy.