Total error is the sum of the sampling and non-sampling errors in a survey. Trace Analysis see indirect observation. Tracking Study is a study that provides periodic updating of company and competitor performances on criteria other than sales. Trade Off Analysis see conjoint analysis. Transcribing see data entry.
Treatment refers to the manipulation of one or more independent variables during an experiment.
Triad see friendship pair interview. Triangle Group is a focus group with three participants who each have differing viewpoints. Triangle Product Test is a type of blind test that involves two similar products to determine the degree to which potential consumers can differentiate between them. Two of the products are identical and one is different. Participants are asked to test all three and indicate which two are similar to each other.