Do local elections matter? In Britain, like in many other countries, we often see them as crucial indicators of the future general election performance of political parties and their leaders. They also have national political significance. Local election success in 2009 brought good press for former Prime Minister David Cameron before his national victory a year later; huge losses in local elections in 2019 helped sink the leadership of his successor Theresa May. Yet, the methods used to study local elections in Britain do not provide a clear or consistent indicator of how well parties are doing nationwide or how they will go on to fair at future national polls. The 2022 local elections, for instance, provided just such a …

When does traditional statistical modelling (TSM) become machine learning (ML)?[i] “Machine learning” has truly become a buzzword that is applied rather liberally to a wide range of modelling applications. But, the difference is far from a question of semantics: there are fundamental differences between ML and TSM that data practitioners should keep in mind. Similarities But, let’s start off with some commonalities between ML and TSM. In both disciplines our aim is to build a (statistical) model (to use TSM terminology) that minimises loss, that is, that achieves the smallest possible difference between observed values and the values estimated by the model. In so doing, we have to achieve a successful balance between model complexity and generalisability: pick too complex a …

A few months ago, I published an exceptionally short paper presenting experimental evidence on a particular issue of survey methodology. This experience has taught me valuable lessons about conveying the necessary information under extreme restrictions on the word count. In its original version, my paper was 2,300 words long and it was formatted in accordance with the convention of the field: an introduction highlighting the relevance of the research question and the gaps in the existing literature, an empirical section describing the methods and presenting the results, and a conclusion discussing implications, limitations, and offering directions for future research. Since the study relied on experimental methods and was already short, I decided to submit this contribution to the Journal of …