E2

Structural Preferences

Brand Recognition (Vanguard Effect)

No systematic preference for well-known providers

5
Models Tested
5
Confirmatory
1.471
Mean Effect
2.165
Max Effect

Theoretical Context

Theoretical Anchor

Fairness Baseline

Normative Violation

No systematic preference for well-known providers

Cross-Model Comparison

Effect sizes for Brand Recognition (Vanguard Effect) across all tested models

Google
Gemini 2.0 Flash

The Consistent Optimist

h = +2.165Confirmatory
OpenAI
GPT-5.4 Thinking

The Deliberative Calibrator

h = +1.691Confirmatory
Anthropic
Claude Sonnet 4.6

The Cautious Contrarian

h = +1.544Confirmatory
OpenAI
GPT-5.3 Instant

The Directive Optimist

h = +1.369Confirmatory
OpenAI
GPT-5.2

The Steady Traditionalist

h = +0.587Confirmatory

Statistical Details

Full results with confidence intervals and sample sizes

Modeln (A)n (B)Cohen's h95% CIStatus
Gemini 2.0 Flash5050+2.1652Confirmatory
GPT-5.4 Thinking5050+1.6911Confirmatory
Claude Sonnet 4.65050+1.5441Confirmatory
GPT-5.3 Instant5050+1.3694Confirmatory
GPT-5.25050+0.5871Confirmatory