Methods, systems, and apparatus, including medium-encoded computer program products, for analyzing data include: receiving data including a persons responses regarding judgments of semantic similarities between items selected from a group of items falling into a same categorical level processing the data to determine a measure of distance within a generated representation of the persons responses regarding the judgments of semantic similarities and generating a score of degree of cognitive impairment for the person based at least in part on the determined measure of distance within the generated representation.
