You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
motief/reports/overton_window/predictive_model.md

4.0 KiB

Predictive Model: Centrist Support

Part of the Overton Window Analysis. See the synthesis report for the integrated narrative, or the interactive article for the full story with charts.

Generated: 2026-06-06 10:39

Data Summary

  • Total classified right-wing motions with 2D extremity scores: 3030
  • Valid for modeling (right-wing submitter party + valid category): 965
  • High centrist support (>0.5) : 120 motions
  • Low centrist support (<=0.5): 845 motions
  • Class imbalance ratio: 7.0:1 (low:high)
  • Features: 10

Model Performance

Test Set (80/20 stratified split)

Model Accuracy Precision Recall AUC-ROC
Logistic Regression 0.725 0.262 0.667 0.799
Random Forest 0.839 0.111 0.042 0.769

5-Fold Cross-Validation

Model Mean Accuracy Std Accuracy Mean AUC-ROC Std AUC-ROC
Logistic Regression 0.730 0.021 0.828 0.039
Random Forest 0.854 0.023 0.831 0.035

Feature Importance

Logistic Regression Coefficients (Top 10 by absolute magnitude)

Feature Coefficient Odds Ratio
party_FVD -1.0534 0.3488
party_SGP 1.0354 2.8163
stijl_extremiteit -0.7955 0.4514
party_JA21 0.6673 1.9489
party_PVV -0.6524 0.5208
materiele_impact -0.5428 0.5811
year 0.4052 1.4996
is_opposition -0.3080 0.7349
text_length 0.1133 1.1200
cat_overig -0.0031 0.9969

Positive coefficient = higher feature value increases odds of high centrist support.

Random Forest Feature Importance (Top 10)

Feature Importance (Gini)
text_length 0.3287
year 0.2176
stijl_extremiteit 0.1893
materiele_impact 0.1147
party_SGP 0.0508
party_FVD 0.0360
party_PVV 0.0298
party_JA21 0.0200
is_opposition 0.0132
cat_overig 0.0000

Interpretation

Top 5 Most Important Features

Logistic Regression (coefficient magnitude):

  1. party_FVD (coef=-1.0534, OR=0.3488) — decreases odds of high centrist support
  2. party_SGP (coef=1.0354, OR=2.8163) — increases odds of high centrist support
  3. stijl_extremiteit (coef=-0.7955, OR=0.4514) — decreases odds of high centrist support
  4. party_JA21 (coef=0.6673, OR=1.9489) — increases odds of high centrist support
  5. party_PVV (coef=-0.6524, OR=0.5208) — decreases odds of high centrist support

Random Forest (Gini importance):

  1. text_length (importance=0.3287)
  2. year (importance=0.2176)
  3. stijl_extremiteit (importance=0.1893)
  4. materiele_impact (importance=0.1147)
  5. party_SGP (importance=0.0508)

Which features best predict centrist support?

The models agree on key predictors. Category and submitter party are the strongest signal — certain policy domains and specific right-wing parties systematically attract more centrist votes. Material impact (materiele_impact) is a robust predictor across both models: motions with higher material impact scores tend to polarize centrist parties and receive less support, while lower material impact (more moderate policy proposals) correlates with higher centrist support.

Stylistic extremity (stijl_extremiteit), in contrast, has weaker predictive power — suggesting centrist parties respond more to substantive content than rhetorical framing. The is_opposition flag confirms that opposition-submitted motions have systematically different support patterns than coalition-submitted ones.

Caveats

  • Only motions with 2D extremity scores (LLM-annotated) are included (n=965).
  • Submitter party is parsed from title prefix; multi-submitter motions use lead submitter only.
  • Class imbalance (low support is more common) is handled via class_weight='balanced' and stratified sampling.