A vision scientist was examining whether human depth perception relies on contextual visual information (i.e., depth cues). He constructed an experiment in which participants viewed an object in virtual reality and had to estimate how far away the object was. Participants repeated this many times and the researcher computed how accurately participants were able to infer the depth of the object. Accuracy was operationalized as the difference between participant estimates of object distance and the true distance of the object. On half of the trials, the object appeared in a long hallway with realistic dcor, thus providing contextual depth cues. On the other half of trials, the object appeared in a white void of empty space. Participants experienced both trial types in randomized order and their accuracy was compared between the hallway and void conditions. If depth is inferred from visual cues, accuracy should be lower in the void condition than in the hallway condition. What analysis should the vision scientist perform to examine whether subjects we less able to infer depth when deprived of depth cues?