We systematically analyse how parliamentary discussion changes in response to different types of events in Australian history.

We first create a dataset of what was said in the Australian Federal Parliament from 1901 through to 2017 based on available public records. To reduce the dimensionality of this dataset we use a correlated topic model, and then analyse the effect of various events using a Bayesian hierarchical Dirichlet model.

We find that:

• changes in government tend be associated with topic changes even when the party in power does not change;
• elections that do not result in a change in government are rarely associated with topic changes;
• economic events, such as financial crises, have less significant effects than other events such as terrorist attacks; and
• that the effect of events have become more pronounced in the past two decades.

Our findings have implications for how we think about the longer-term trajectory of government policymaking as the media and political cycles becomes increasingly focused on short-term events.

About the presenter:

Rohan Alexander is a PhD student at the Australian National University. His research focuses on Australian political history. His current projects involve exploring: the impact of various events on discussion in state and federal parliaments; who voted for Federation; and which politicians get an incumbency effect.