Explore similarity of manuscripts' differentia, by monastic order, or cathedral. Notice the close similarity of manuscripts, not only from the same geographic regions, but also the same institution type, especially Franciscan, Dominican, Cistercian, and Cathedral. Select items under "Order" to highlight corresponding values in the map and graph, or select individual manuscripts in the graph view to highlight their location on the map. Note that one point on the map may represent multiple manuscripts.
The similarity score considers the ratio of shared differentiae between two sources. If none of the differentiae in manuscript A appear in manuscript B, it would suggest that the chant traditions of the two manuscripts are unrelated; if all of the differentiae in A are also in B, it would suggest that there is an extremely close connection between the two.
Similarity scores for all manuscripts in the Differentiae Database were calculated by calculating the average of two ratios: (1) number of shared differentiae between A and B to the total number of differentiae in A; and (2) number of shared differentiae between A and B to the total number of differentiae in B.
For example, CH-Fco 2 has 44 unique differentiae and D-Ma 12o Cmm 1 has 52 unique differentiae; 27 differentiae appear in both manuscripts. Therefore, CH-Fco 2 and D-Ma 12o Cmm 1 have a similarity score of 0.57 [(27/44 + 27/52)/2]. As each score approaches 1.00, the level of similarity between two manuscripts increases. Each manuscript has a score of 1.00 with itself.
Select any manuscript in the right-hand graph to highlight its location in the map. Select any of the items in the "Order/Cathedral" legend to highlight all of the Cistercian, Dominican, Franciscan, etc. manuscripts in the map and in the graph.