One-third hypothesis be the ones most significantly implicated in ongoing sociocultural transformation. This does not mean that these groups need to be dominant, but they play prominent roles." The OTH involves two mathematical curves. One represents the likelihood that a subgroup of a specific size will emerge; the other is the probability that it will persist. The product of the two curves is the one-third hypothesis. Statistically speaking, the group that is one-third of the population is the one most likely to persist and the group that is two-thirds the one most likely to dissolve into splinter groups, as if reacting to
Ladder of thirds Ladder of thirds A ladder of thirds (coined by van der Merwe 1989, adapted from Curt Sachs) is similar to the circle of fifths, though a ladder of thirds differs in being composed of thirds, major or minor, and may or may not circle back to its starting note and thus may or may not be an interval cycle. Triadic chords may be considered as part of a ladder of thirds. It is a modal frame found in Blues and British folk music. Though a pentatonic type, the melodies come "into being through piling up thirds below and/or above a