🔎 What Was Studied
This study evaluates the claim that backbench members of the UK House of Commons have grown less distinctive in their speech over time — a question with clear normative and substantive implications. Prior theory and evidence on this topic are mixed and do not settle the issue.
🧾 A Century of Hansard Speeches
- Corpus: Hansard speeches spanning 1935–2018
- Population of interest: backbench MPs in the UK House of Commons
🧠 A New Model of Author "Style"
- Introduces a general statistical model of distinctiveness that extends traditional approaches to characterizing an author’s style (stylometry).
- Applies this model to the Hansard corpus to generate measures of how "different" each MP's speech is relative to others.
📈 Key Findings
- Aggregate pattern: No evidence that backbench MPs have become more homogeneous in speech across the full 1935–2018 period.
- Covariate effects at the MP level: Panel regression analysis shows that, on average, more senior backbenchers tend to be less distinctive in speech.
- Time change: The above seniority pattern is shifting — in recent years, more experienced MPs are the ones who speak most distinctively.
⚠️ Why It Matters
- The results complicate broad claims about growing speech homogeneity in Parliament by showing different patterns at aggregate and individual levels.
- Findings matter for theories of representation, career incentives, and parliamentary communication, and suggest that changes in who speaks distinctively are driven by covariates like seniority and changing temporal dynamics.
