Effect of Data Annotation, Feature Selection and Model Choice on Spatial Description Generation in French

In this paper, we look at automatic generation of spatial descriptions in French, more particularly, selecting a spatial preposition for a pair of objects in an image. Our focus is on assessing the effect on accuracy of (i) increasing data set size, (ii) removing synonyms from the set of prepositions used for annotation, (iii) optimising feature sets, and (iv) training on best prepositions only vs. training on all acceptable prepositions. We describe a new data set where each object pair in each image is annotated with the best and all acceptable prepositions that describe the spatial relationship between the two objects. We report results for three new methods for this task, and find that the best, 75% Accuracy, is 25 points higher than our previous best result for this task.