Poll Herding Regression
Identifies when pollster consensus is too perfect.
Overview
This pillar detects poll herding, a phenomenon where pollsters' results cluster too tightly together to avoid being outliers. Identifying this signals a fragile consensus and a higher probability of a surprise election outcome.
What It Does
It analyzes the statistical distribution of recent polls for a specific political race, focusing on the variance and standard deviation of the results. The model compares this current variance to a historical baseline for similar types of races. Unusually low variance for the current period triggers a high 'Herding Score', suggesting pollsters may be influencing each other's results.
Why It Matters
A herd mentality among pollsters can mask the true volatility of a race and create a false sense of certainty. This pillar provides a contrarian signal, highlighting markets where the favorite may be more vulnerable than the consensus believes, creating high-value trading opportunities.
How It Works
First, the system aggregates all qualifying polls for a given race over the last 30 days. It then calculates the standard deviation of the vote margin across these polls. This figure is compared to a pre-calculated historical average standard deviation for analogous races. A final score is generated based on how far below the historical norm the current polling variance falls.
Methodology
The core calculation is the Herding Index (HI) = (1 - (Current_SD / Historical_SD)) * 100. 'Current_SD' is the standard deviation of poll margins in a 30-day window. 'Historical_SD' is the average standard deviation from the final 30 days of all similar races (e.g., competitive Senate races) over the past three election cycles. An HI score over 60 is considered a strong signal of herding.
Edge & Advantage
This model offers an edge by quantifying a qualitative phenomenon. It moves beyond simple polling averages to analyze the second-order behavior of the pollsters themselves, revealing hidden risk in markets that appear stable.
Key Indicators
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Polling Standard Deviation
highMeasures the statistical spread of recent poll results. A very low value is a primary red flag for herding.
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Outlier Count
mediumThe number of polls falling outside two standard deviations of the mean. A count of zero can indicate herding.
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Historical Variance Ratio
highCompares the current polling variance to the historical average for similar races. A ratio below 0.7 suggests herding.
Data Sources
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Provides raw polling data and pollster ratings for U.S. elections, essential for historical baselines.
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Aggregates a wide range of polling data from various sources for current political races.
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Offers race ratings and historical context, helping to define 'similar races' for comparison.
Example Questions This Pillar Answers
- → Will the Republican candidate win the Senate race in Nevada?
- → What will be the final vote margin in the Ohio 13th congressional district election?
- → Will Democrats retain control of the Senate in the 2024 election?
Tags
Use Poll Herding Regression on a real market
Run this analytical framework on any Polymarket or Kalshi event contract.
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