Questions tagged [pareto-distribution]

The Pareto distribution is a power distribution which was initially invented to describe the distribution of income but has found application in many other areas.

The Pareto distribution was developed in the late 19th century by Italian economist Vilfredo Pareto to describe the allocation of income and wealth among individuals. The distribution has found application in many other areas such as computing science, civil engineering, stock markets, physics, astronomy or insurance.

Its pdf is given by:

$$ f(x|a,b) = \frac{ba^b}{x^{b+1}} $$

for $x \geq a > 0$ and $b>0$, where $a$ provides the lower bound that a Pareto distributed random variable can take whilst $b$ determines the heaviness of the right tail.

The first two moments are:

\begin{align} &\text{mean: }& &\frac{ab}{b-1} \\[7pt] &\text{variance (when }b>2\text{): }& &\frac{ba^2}{(b-1)^2(b-2)} \end{align}

186 questions
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Why does the $\alpha$ parameter grow to $\infty$ in Pareto-distributed random numbers when changing the threshold?

I noted a strange fact. Let X be a set of Pareto distributed random number with $\alpha$ and $x_{\min}$ defined a priori. Now, let $\alpha'$ be the estimated value of the shape and $x_{\min}'$ be a new threshold fixed a posteriori. If…
emanuele
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How to extract 20-80 relations from data (Pareto principle)?

There are certain input-output processes that display a "20-80 relation". That is, given Y depending on X, there are subsets of X consisting 20% of the input set that generate 80% of the output. For example, 20% of clients may generate 80% of…
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MLE of truncated Pareto distribution

I am trying to apply truncated Pareto distribution to a dataset, but I am not able to find a close form MLE for the shape parameter alpha. Could anyone help me with this: how to estimate the shape parameter for the truncated Pareto distribution.
Aragorn
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Pareto Variable Transformation

A random sample, $X_1, X_2,... X_n$ is drawn from a Pareto population with pdf $$f(x|\theta)=\frac{\theta}{x^2}I_{[\theta,\infty)}(x)$$ I've been trying to figure out the distribution of $$T=\log\Big[\frac{\prod_{i=1}^n X_i}{X_{(1)}^n}\Big]$$ where…
diidoobiib
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How to write the set of indexes of Pareto optimal reward set in formal methods

I denote that a reward vector of an item $a$ as $r_a$. Say there is a set of items denoted as $A_t$. I want to get a set $A^\prime_t$ of items from $A_t$ that has non-dominated reward vectors. For a given two items $m, n$, if $n$ has a reward vector…
user77005
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Long tail of pareto vs. pearson IV distribution

I am told that wealth follows a Pareto distribution, and that IQ follows a Pearson IV distribution (http://www.abelard.org/burt/burt-ie.asp). Both Pareto and Pearson IV distributions have long tails. Which one is longer? In plain language: are…
Didier
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Expectation of the Pareto distribution

I would like to know if my understanding of the following is correct. This has been tripping me up for a long time now. Compute $\lim_{x\rightarrow \infty}x^{1-\beta}$. This is part of a homework problem regarding the expectation of the Pareto…
user30602
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Number of ten millionaires in a country

Given that I know the number of billionaires B and millionaires M in a society and that wealth is distributed in as a Pareto, how do I figure out the number of people with more than 10 million dollars?
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Extending the 80/20 rule

I have seen comments on the web that because the 80/20 rule is fractal, it applies to the sub groups. In other words, if the top 20% of causes drive 80% of outcomes, then the top 4% of causes must drive 64% of outcomes, etc. Can that be extended…
Guest
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How does the Pareto principle give the 80/20 rule?

It seems to me that the Pareto principle says that for any $n$-many people that produced $m$-many goods, $\sqrt[2]{n}$-many people would produce $\frac{m}{2}$ many goods out of the total $m$ many goods (until all the goods are produced, then the…
caveman
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