I590/N564/N364 QUIZ #1 - 25 January 2006
Total: 70 points (+10 extra credit)

                                                 Name _____________________________
													

	According to both the Byrd and Crawford paper "Problems of Music Information
	Retrieval in the Real World" (henceforth "B+C") and my lectures, the three basic
	representations of music and audio are: audio; MIDI; and music notation.
	
	
	1. What, according to both B+C and my lectures, is the _most important_
5>	feature that differentiates among the three? Say both (a) what the feature is
10>	called, and (b) what it means, i.e., define it.
	
		(a) THE AMOUNT OF EXPLICIT STRUCTURE
	
		(b) HOW MUCH ORGANIZATION IS _CLEARLY_ PRESENT; HOW MANY FEATURES OF THE
		MUSIC ARE LABELLED AS TO WHAT THEY ARE. Music notation has symbols for
		clefs, key signatures, expression marks, rests, etc., and ways to specify
		voicing and timbre as well as notes, when they start and stop, and their
		loudness. MIDI has only the last few of these (though you may be able to
		_infer_ the others); audio has none (though you may be able to infer some).
	

	2. According to B+C and my lectures, two of the three forms are ideally suited
		for music only.
5>	Which form is also ideally suited for something else?
	
		AUDIO	
	

5>	3. Which form nearly always takes the most space (in a file)?
		
		AUDIO
	

	4. B+C discuss such music-perception and related phenomena as streaming,
	perception of wide skips (which can be affected by listeners hearing notes
	as if they're in different octaves and by texture changes), salience, and
10>	melodic confounds; I played examples in class of the first two. (a) Define
	one of these phenomena.
	
		STREAMING: the psychoacoustic effect in which a series of individual events
		heard (for music, a monophonic series of notes) is perceived as being
  		divided into two or more simultaneous "lines".
		
		PERCEPTION OF WIDE SKIPS: how skips of large melodic intervals (probably
		well over an octave) are heard. (Listeners may misjudge the intervals
		because they hear the notes involved as if they're in different octaves than
		they actually are; in addition, texture changes in the music may lead to
		ambiguity as to how large the intervals "really" are.)
		
		SALIENCE: the extent to which something gets our attention, for whatever
  		reason; how significant something is in terms of perception.
		
		MELODIC CONFOUNDS: elements that are believed to complicate perception of
		melodies because they can easily be heard in different ways or missed
		completely. Examples include rests, repeated notes, and grace notes, and
		perhaps ornaments like trills.
	
10>	(b) (extra credit) How could that phenomenon confuse a program?
	
		(MANY POSSIBLE ANSWERS; SEE B+C)	
	
	
15>	5. Why is musical information hard to handle? B+C discuss several reasons;
	in my lectures, I singled out two main reasons that apply to all three forms.
	Name one of these main reasons and say something about it (one or two
	substantial sentences will do).
	
	EITHER UNITS OF MEANING (or SEGMENTATION or similar), OR
	POLYPHONY (or MULTIPLE INDEPENDENT VOICES or similar)


	6. The "Similarity Scale for Content-Based Music IR" has eight categories:
	no. 1 is "Same music, arrangement, performance, & recording" and no. 8 is
10>	"No relationship". Pick any two of categories 2 thru 7 (of course I
10>	won't expect you to remember the exact wording of my description, or the
	category number!); for each, describe it and give a scenario in which it
	might be useful.
	
	ANY TWO OF:
	  2. Same music, arrangement, performance; different recording
	 
	  3. Same music, arrangement; different performance, recording
	 
	  *4. Same music,* different arrangement; or *different but
	  closely-related music,* e.g., conservative variations (Mozart, etc.),
	  many covers, minor revisions

	  5. Different & less closely-related music: freer variations (Brahms,
	  much jazz, etc.), wilder covers, extensive revisions

	  6. Music in same genre, style, etc.

	  7. Music influenced by other music