(i) Any test for extrasensory perception which uses target material and forms of response which do not allow a definite probability-value to be attached to the response items made; examples are most free-response tests, tests of psychometry, mediumistic utterances, and so on; statistical evaluation of such data must therefore proceed in an indirect fashion, by assigning a probability-value to the matching-performance of a judge; (ii) Any attempt to demonstrate qualitative phenomena. Compare Quantitative Experiment. [Ultimately derived from the Latin qualis, “what kind of?”]