10 Downing Street: who’s next? Seemingly unrelated regressions to forecast UK election results

Abstract

In recent years, the British polling industry has encountered difficulties in its attempts to measure voting intentions in important popular consultations, notably the referendum on Scottish independence, the 2015 general election and the EU membership referendum. In such a context, it is extremely valuable to explore how different forecasting models that use political and economic variables can be used to predict the outcome of elections. In this paper, we propose such a model by introducing a political economy equation to estimate the vote share obtained by the incumbent party in UK general elections three months before the vote as well as a set of seemingly unrelated regressions (SUR) to forecast the results of the Official Opposition, the Liberal Democrats and the remaining parties.

Forecasting the 2022 French Presidential Election: From a Left–Right Logic to the Quadripolarization of Politics

“…The SUR model was used because it considers the possibility that the determinants of voting for one candidate also may determine the vote for other candidates. Contrary to the ordinary least squares approach, the SUR model does not assume that the error term of an equation (i.e., roughly representing the relevant factors omitted from the analysis) is uncorrelated with the error term of the other equations-a highly improbable possibility when using election-results data (Mongrain 2021;Timm 2002;Tomz, Tucker, and Wittenberg 2002). 1 Our SUR model of the presidential election was estimated for the 1965-2017 period (i.e., 10 presidential elections) and included five equations.…”

Predicting in an (increasingly) unpredictable system? Forty years of election forecasting in France

“…The SUR method offers a worthy solution to the problems that would arise from the estimation of multiple and distinct equations. Since Arzheimer and Evans (2010), multiparty equation systems have also been proposed for British and German elections (see Jérôme et al 2017;Mongrain 2021;Quinlan et al 2022). as well as Jérome-Speziari and have recently applied this approach to the 2022 French presidential elections.…”

Forecasting Bloc Support in German Federal Elections: A Political-History Model

“…First, we spurn the dominantgovernment-versus-opposition paradigm and predict the performance of individual blocs. Although this approach is not new to the structural approach per se (Jérôme, Jérôme-Speziari, and Lewis-Beck 2013;Mongrain 2021;Stoetzer et al 2019), our effort eschews any public-opinion measures. Second, and more innovatively, we focus exclusively on the undermined dimension of a country's political history.…”