James David Griffiths

@jamesdgriffiths.bsky.social

668 Followers 231 Following

Research Fellow at the British Election Study, Wrexham and Wales fan

Graph showing the number of votes a party would need to win one more seat in each constituency
Graph showing a heat map of the vote share received by the six major parties in the 2026 Senedd election.
Left graph shows votes (constituency+region) and seat shares of Senedd election in 2021, and right graph shows the same for 2026
Graph showing the Gallagher index for every Senedd and UK General election in Wales. UK General Elections are very disproportional, the Senedd elections less so, but the new election system wasn't an improvement.
Graph showing the percentage vote share that the winning party received for each seat round in the 2026 Senedd election. Parties needed sequentially fewer votes to win each seat.
Three graphs showing within-individual change in Britishness in Britain between 2016 (pre-referendum) and 2020. The top left graph shows the results from an OLS regression, where someone's Britishness in 2016 is subtracted from their Britishness in 2020. The value indicates the average difference between the two values among Remain voters and Leave voters. The top right graph shows the results from a Latent Growth Curve Model, which represents the average change in Britishness between 2016 and 2020 among Remain and Leave voters. The bottom graph shows the results of a two-way fixed-effects model, indicating the average within-individual change in Britishness among Remainers relative to Leavers between 2016 and 2020. All models show the same thing: Britishness declined far much more during this period among Remainers than it did among Leavers.
Graph showing the reasons given why someone thought Labour was doing a bad job in the Welsh Goverment, split by vote intention for British/right/conservative parties (Reform and Tories) and Welsh/left/liberal parties (Labour, Green, Plaid Cymru, Liberal Democrats). Most commonly cited reasons are the NHS, a general non-specific dissatisfaction, the cost of living, transport, and wasteful spending. Data was open text, and then coded by Claude and verified by manual coding.
Graph showing the percentage of people who like a party who said that they did (in 2024) or would (in 2025) vote for that specific party. Greens convert the fewest people who strongly like them into voters, even in 2025 (when their vote share has increased).
Video of a man talking about the by-election in Gorton and Denton.
Graph showing support for the Welsh/left bloc and British/right bloc by national identity in 2021 and 2025. Labour has lost basically all support among Welsh identifiers to Plaid, whereas the Tories have lost the support of British identifiers to Reform
Like ratings for the major political parties by pre-referendum/pre-election vote intention in 2016, 2019, and 2024, excluding the party that someone said they'd vote for
Vote choice for the left-liberal and right-conservative blocs among the four constitutional camps in Scotland (Yes/Remain, Yes/Leave, No/Remain, and No/Leave). Most Remain voters are aligned on Brexit, whereas Leave voters are less so (but still mostly aligned) due to independence.
Vote choice for the left-liberal and right-conservative blocs by age in 2015, 2017, 2019, and 2024. Most young people back left-liberal parties in each era (but particularly post-Brexit) and most older people back right-conservative parties (but particularly post-Brexit). Labour has lost support among younger people, but they went mostly to the Greens and Liberal Democrats. Conservatives have lost support to everyone, but they mostly went to Reform.
Mean perceived positions of political parties on redistribution, (left-right), EU integration, and immigration (liberal-authoritarian), in 2019 and 2024 in Britain. Redistribution: 0: Government should try to make incomes equal; 10: Government should be less concerned about equal incomes. Immigration: 0: Many fewer; 10: Many more (we flip the order so that both scales move from 0 = support, 10 = oppose). EU Integration: 0: Unite fully with the European Union; 10: Protect our independence.
Sankey diagram showing vote flows between 2019 and 2024. Most people who backed Leave in 2019 still backed a pro-Leave party in 2024, whereas most people who backed Remain in 2019 still backed a pro-Remain party in 2024.
4 graphs showing overall volatility, the pedersen index, two party (Conservative and Labour) vote share, and the effective number of parties in Britain between 1964 and 2024. Taken together, the graphs show that things have been becoming more volatile and more fragmented over time.