# Identification and Description of Outliers in the [PERSON] Collection of Native American Music
## 4 Outliers in the Densmore Collection of Native American Music
### Outlier Songs with Unusual Feature Combinations  
While [PERSON]'s tabular analyses consider each attribute on its own (Figure 1 left), computational analysis supports systematic consideration of feature combinations. Table 5 lists six of the 16 outliers suggested by infrequent feature sets. In these cases it is not the individual feature which is rare but the co-occurrence of the features participating in the patterns; hence this is different from songs ID1303 and ID1474 in Table 4 which satisfy more than one infrequent single-feature pattern. For example, 68 (41%) of the Papago songs in the corpus end on the keynote, but only two of these, songs ID930 and ID954, start on the octave above the keynote. Among Menominee songs in the collection, 40% have a compass of between five and eight tones and 31% start with an ascending interval, but only 10% satisfy both of these features. In fact, in her description of song ID1609 [PERSON] points out that the compass of eight tones is shared among several Menominee songs. In the three examples in Table 5 in which [PERSON] highlights a property which is unusual (songs ID930 and ID1607) or interesting to note (song ID1632), her narrative description is more specific than the attributes underlying her quantitative analysis (firstReKey and firstDir): in song ID930, the initial tone is the octave above the keynote additionally characterised by the duration of a half note; for songs ID1607 and ID1632, the textual description further specifies the upward-directed motion at the beginning of the song by its interval. The results demonstrate that the computational outlier detection method can discover significantly infrequent feature sets, but generally mining for minimal infrequent contrast patterns favours short, even single-feature, patterns; in the current study, this facilitates the comparison of computationally discovered outliers with [PERSON]'s own analyses.  
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Song** & **Group** & **Outlier Description** \\ \hline ID930 & Papago & \{firstReKey: octave, lastReKey: keynote\} \\  & & “The melodic formation of this song is unusual. The song begins with a half note on the highest tone of the compass. This tone is the keynote [octave] and does not occur again in the song.” ([12], p. 200) \\ ID954 & [PERSON] & \{firstReKey: octave, lastReKey: keynote\} \\  & & “The song has a range of an octave and a steadily descending trend.” ([12], p. 37) \\ ID1540 & [PERSON] & \{compass: five\_to\_eight\_tones, firstDir: up\} \\  & & “The ascent of an octave at the opening was changed to a major sixth in the repetition of the melody.” ([14], p. 206) \\ ID1607 & [PERSON] & \{compass: five\_to\_eight\_tones, firstDir: up\} \\  & & “The opening intervals are unusual and comprise an ascending whole tone followed by an ascending seventh.” ([14], p. 66) \\ ID1609 & [PERSON] & \{compass: five\_to\_eight\_tones, firstDir: up\} \\  & & “This song resembles others of the present group in having a compass of eight tones, lying partly above and partly below the keynote.” ([14], p. 67) \\ ID1632 & Menominee & \{compass: five\_to\_eight\_tones, firstDir: up\} \\  & & “It is interesting to note the ascent of an octave within three intervals at the opening of the song and in one interval, midway the length of the song.” ([14], p. 207) \\ \hline \hline \end{tabular}
\end{table}
Table 5: Outliers in the [PERSON] collection with significantly infrequent feature combinations.