Quantitative Measurement of Parliamentary Accountability using Text as Data: the Canadian House of Commons, 1945-2015

How accountable is Canada’s Westminster-style parliamentary system? Are minority parliaments more accountable than majorities, as contemporary critics assert? This dissertation develops a quantitative measurement approach to investigate parliamentary accountability using the text of speeches in Hansard, the historical record of proceedings in the Canadian House of Commons, from 1945-2015. The analysis makes a theoretical and methodological contribution to the comparative literature on legislative debate, as well as an empirical contribution to the Canadian literature on Parliament. I propose a trade-off model in which parties balance communication about goals of office-seeking (accountability) or policy-seeking (ideology) in their speeches. Assuming a constant context of speech, I argue that lexical similarity between government and opposition speeches is a valid measure of parliamentary accountability, while semantic similarity is an appropriate measure of ideological polarization. I develop a computational approach for measuring lexical and semantic similarity using word vectors and the doc2vec algorithm for word embeddings. To validate my measurement approach, I perform a qualitative case study of the 38th and 39th Parliaments, two successive minority governments with alternating governing parties. I find that similarity scores are positively related with the substantive quality of opposition questions and government responses. In the quantitative analysis phase, I study Question Periods from 1975-2010 and daily debates from 1945-2015 using the lexical similarity measurement. I find that minority parliaments are more account- able than majority governments since the 30th Parliament, but find no significant relationship between government seat percentage and parliamentary accountability. I show that Parliament becomes more accountable as a government’s popularity decreases. However, the data more strongly support a non-linear model. A structural break analysis yields one significant break at 33%: below this critical value, polling popularity and parliamentary accountability are positively related, and above, are negatively related. Finally, I confirm that the correlation between measures of lexical and semantic similarity varies in strength and direction across parliamentary sessions, suggesting two distinct generative processes are indeed at work.Ph.D