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
Riff-driven songs are largely a product of jazz, blues, and post-blues era music (rock and pop). The musical goal of riff-driven songs is akin to the classical continuo effect, but raised to much higher importance (in fact, the repeated riff is used to anchor the song in the ears of the listener).