Obtaining such questions is hard for two reasons: (1) teaching crowdworkers about coreference is challenging, with even experts disagreeing on its nuances (Pradhan et al., 2007;Versley, 2008; Re-Byzantines were avid players of tavli (Byzantine Greek: τάβλη), a game known in English as backgammon, which is still popular in former Byzantine realms, and still known by the name tavli in Greece.
a: Barack Obama; Obama; Senator Obama Beyond training workers with the detailed instructions shown above, we ensured that the questions are of high quality by selecting a good pool of 21 workers using a two-stage selection process, allowing only those workers who clearly understood the requirements of the task to produce the final set of questions.