A psychologist wants to know whether subjects respond faster to a go/no go stimulus or a choice stimulus. With the go/no go stimulus, subjects must respond to a particular stimulus by pressing a button and disregard other stimuli. In the choice stimulus, the subjects respond differently depending on the stimulus. The psychologist randomly selects 20 subjects, and each subject is presented a series of go/no go stimuli and choice stimuli. The mean reaction time to each stimulus is compared.

Determine whether the sampling is dependent or independent. Indicate whether the response variable is qualitative or quantitative.