This has often been based on single-domain datasets, and examples include (for English unless otherwise noted) movie reviews collected from aggregator sites like IMDb.com (Pang and Lee, 2004;Maas et al., 2011) and RottenTomatoes.com (Pang and Lee, 2005;Socher et al., 2013), hotel reviews from TripAdvisor (Wang et al., 2010), book reviews (in Arabic) (Aly and Atiya, 2013), app reviews compiled from Apple App store and Google Play (Guzman and Maalej, 2014), and reviews of restaurants and other businesses in the Yelp open dataset.
5 the unbalanced nature of these datasets (single domains) can impose inherent limitations on the ability of 5 https://www.yelp.com/dataset models to generalize.