Examples of such models include the WASP system (Wong and Mooney, 2006) which regards the semantic parsing problem as a statistical machine translation problem, the UBL system (Kwiatkowski et al., 2010) which performs CCG-based semantic parsing using a log-linear model, as well as the <cite>relaxed hybrid tree</cite> model <cite>(Lu, 2014)</cite> which extends the generative hybrid tree model.