Abstract
LetA n be the average root-to-leaf distance in a binary trie formed by the binary fractional expansions ofn independent random variablesX 1,...,X n with common densityf on [0, 1). We show thateither E(A n )=∞ for alln≥2or \(\mathop {\lim }\limits_n E(A_n )/\log _2 n = 1\) depending on whether ∫f 2 (x)dx = ∞ or ∫f 2 (x)dx < ∞.
Zusammenfassung
SeiA n der mittlere Wurzel-zu-Blatt-Abstand in einem binären Baum, der durch die Dualbruchentwicklungen vonn unabhängigen ZufallsveränderlichenX 1,...,X n mit gemeinsamer Dichtef auf [0, 1) entsteht. Wir zeigen, daßentweder E(A n )=∞ für allen≥2oder \(\mathop {\lim }\limits_n E(A_n )/\log _2 n = 1\), je nachdem, ob ∫f 2 (x)dx = ∞ oder ∫f 2 (x)dx < ∞.
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Devroye, L. A note on the average depth of tries. Computing 28, 367–371 (1982). https://doi.org/10.1007/BF02279819
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DOI: https://doi.org/10.1007/BF02279819