Title
Total Path Length for Random Recursive Trees
Abstract
Total path length, or search cost, for a rooted tree is defined as the sum of all root-to-node distances. Let Tn be the total path length for a random recursive tree of order n. Mahmoud [10] showed that Wn := (Tn − E[Tn])/n converges almost surely and in L2 to a nondegenerate limiting random variable W. Here we give recurrence relations for the moments of Wn and of W and show that Wn converges to W in Lp for each 0 p W is not normal. We also show that the distribution of W is characterized among all distributions having zero mean and finite variance by the distributional identity***** Insert equation here *****where ℰ(x) := − x ln x − (1 minus; x) ln(1 − x) is the binary entropy function, U is a uniform (0, 1) random variable, W* and W have the same distribution, and U, W and W* are mutually independent. Finally, we derive an approximation for the distribution of W using a Pearson curve density estimator.
Year
DOI
Venue
1999
10.1017/S0963548399003855
Combinatorics, Probability & Computing
Keywords
Field
DocType
random recursive trees,order n,pearson curve density estimator,rooted tree,random variable,random recursive tree,p w,n converges,wn converges,total path length,random variable w.,cumulant,recurrence relation,search cost
Discrete mathematics,Combinatorics,Random variable,Path length,Recurrence relation,Binary entropy function,Almost surely,Recursive tree,Mathematics,Independence (probability theory),Estimator
Journal
Volume
Issue
ISSN
8
4
0963-5483
Citations 
PageRank 
References 
18
1.41
7
Authors
2
Name
Order
Citations
PageRank
Robert P. Dobrow1355.28
James Allen Fill225340.88