The dimensionality of the Scottish political space : results from an experiment on the 2011 Holyrood elections

This article introduces Voting Advice Applications (VAAs) as a data-generating tool that can be used to measure the positions of party supporters in multidimensional policy space. It begins with an overview of the state of the art as regards methods for locating parties on a common policy space, in terms of how data are gathered and also in terms of how policy dimensions are identified and measured. We then use a dimension reduction technique to identify latent policy dimensions from a dataset obtained from a VAA carried out in Scotland in 2011. These dimensions are used to map the policy positions of supporters of five Scottish political parties. We argue that this tool allows more leverage on understanding the relative locations of parties ‘in the electorate’ in multidimensional policy space