# Predeclared case-selection rules

These rules were recorded before inspecting the selected parties' position estimates.

## Trajectory figure

The figure will use parties selected for cross-national recognition, family diversity, long election coverage, and relevance to interpreting movement on the two scales. Selection is not based on the magnitude of the estimated movement.

Preselected parties:

- Germany: Social Democratic Party of Germany (PartyFacts 383)
- Germany: Christian Democratic Union (PartyFacts 1375)
- United Kingdom: Labour Party (PartyFacts 1516)
- United Kingdom: Conservative Party (PartyFacts 1567)
- Denmark: Social Democratic Party, short name SD (PartyFacts 379)
- Sweden: Sweden Democrats (PartyFacts 409)
- United States: Democratic Party (PartyFacts 432)
- United States: Republican Party (PartyFacts 809)

The final display may use a subset only to preserve legibility, but exclusions must be based on panel layout or insufficient coverage rather than unattractive results. Both posterior means and 95% latent-position credible intervals will be shown. Text will not infer a cause of movement from the estimates alone.

## Two-dimensional landmarks

Landmarks will be selected from recognizable party-election cases, with representation of economically left/right, culturally cosmopolitan/traditionalist, and moderate combinations. Target years are declared before checking exact positions; if the requested year is absent, the nearest election within three years will be used and disclosed.

- German Social Democratic Party: 1972 and 2021
- German Christian Democratic Union: 1983 and 2021
- UK Labour Party: 1983 and 1997
- UK Conservative Party: 1979 and 2019
- Swedish Social Democratic Labour Party (PartyFacts 487): 1994 and 2022
- Sweden Democrats: 2010 and 2022
- French National Front (PartyFacts 433): 1988 and 2022
- German The Left (PartyFacts 1545): 2021
- US Democratic Party: 2020
- US Republican Party: 2020

Labels may be pruned only to avoid overlap. The plotting-data table will retain all declared cases, including missing cases and substitutions.