That arises from inaccurate sampling frame, data clarification or verification methods, reporting or coding of data, and/or specifications. It may also arise from poorly designed survey questionnaires, improper sample allocation and selection procedures, and/or errors in estimation methodology.
riff (rÉªf) n. 1. an ostinato melodic phrase accompanying a soloist in jazz or rock music. 2. any variation or improvisation, as on an idea. v.i. 3. to perform a riff. [1930â35; perhaps alter. of refrain 2] riff Past participle: riffed Gerund: riffing
motif noun [C] (IDEA). âº an âidea that is used many âtimes in a âpiece of writing or âmusic: The motif of âbetrayal is âcrucial in all these âstories. (Definition of motif from the Cambridge Advanced Learnerâs Dictionary & Thesaurus Â© Cambridge University Press).