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
Answer: The word riff is used in such genres as pop, rock and jazz. An example of a song that has a memorable riff is Smoke on the Water played by Ritchie Blackmore of Deep Purple. This song has a rock riff that is played using the G pentatonic scale (G, A, B, D, E). It is memorable yet simple to play, that's why it's so popular and most beginning electric guitar players learn to play it first. Watch Ritchie Blackmore as he shows how to play the Smoke on the Water riff.