Hellinger distance

R. Beran, Am. Stat. 5 445 (1977). (The Hellinger distance satisfies the triangle inequality and is invariant under changes of coordinate.)... 

It is very clear that the larger the hidex X, Y) is, the smaller the Hellinger distance between X and Y will be Therefore tndexiX.Y) directly reflects their similarity For example, Anise 2 (9) and Anise /f4(/0) have many volatile compounds in common (Table 11). The similarity index between these two spices is 0.96d indicating high degree of similarity. On the contrary, when volatile compounds of Anise U2 are compared with those of coriander If I (/ /), as shown in Table ill, an index value of 0 is obtained, indicating no similarity between these two spices... 

Although classical CA is based using x -distances, Meyners et al. (2013) suggested using Hellinger distance, which is commonly used to quantify the similarity between two probability distributions (Cuadras and Cuadras, 2006), to minimize the influence of infrequently selected CATA terms on sample and terms configurations. 

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