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| ==Related distributions相关分布== | | ==Related distributions相关分布== |
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− | ! !! \overline{F}(x)=1-F(x) !! Support !! Parameters
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− | !!!1-F (x) ! !支持!参数
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| ===Generalized Pareto distributions广义帕累托分布=== | | ===Generalized Pareto distributions广义帕累托分布=== |
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− | {{See also|Generalized Pareto distribution}}
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− | {{另见广义帕累托分布}}
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− | | Type I
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− | | 第一类
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| 帕累托分布有一个层次结构<ref name=arnold/><ref name=jkb94>Johnson、Kotz和Balakrishnan(1994),(20.4)。</ref>帕累托分布被称为帕累托类型I、II、III、IV,费勒-帕累托分布。<ref name=arnold/><ref name=jkb94/><ref name=kk03>{cite book | author1=Christian Kleiber | author2=Samuel Kotz | lastauthoramp=yes | year=2003 | title=经济学和精算科学中的统计规模分布| publisher=[[John Wiley&Sons | Wiley]]| isbn=978-0-471-15064-0 | ref=harv |网址=https://books.google.com/books?id=7wLGjyB128IC}}</ref>Pareto类型IV包含Pareto类型I-III作为特殊情况。费勒-帕累托<ref name=jkb94/><ref name=Feller>{cite book | last=Feller | first=W.| year=1971 | title=概率论及其应用简介| volume=II | edition=2nd | location=New York | publisher=Wiley | page=50}“密度(4.3)有时以经济学家‘Pareto’的名字命名。人们认为(从现代统计观点来看,这一点相当幼稚),收入分配应该有一个密度为“Ax”<sup>—“α”</sup>为“x”→∞的尾部。 | | 帕累托分布有一个层次结构<ref name=arnold/><ref name=jkb94>Johnson、Kotz和Balakrishnan(1994),(20.4)。</ref>帕累托分布被称为帕累托类型I、II、III、IV,费勒-帕累托分布。<ref name=arnold/><ref name=jkb94/><ref name=kk03>{cite book | author1=Christian Kleiber | author2=Samuel Kotz | lastauthoramp=yes | year=2003 | title=经济学和精算科学中的统计规模分布| publisher=[[John Wiley&Sons | Wiley]]| isbn=978-0-471-15064-0 | ref=harv |网址=https://books.google.com/books?id=7wLGjyB128IC}}</ref>Pareto类型IV包含Pareto类型I-III作为特殊情况。费勒-帕累托<ref name=jkb94/><ref name=Feller>{cite book | last=Feller | first=W.| year=1971 | title=概率论及其应用简介| volume=II | edition=2nd | location=New York | publisher=Wiley | page=50}“密度(4.3)有时以经济学家‘Pareto’的名字命名。人们认为(从现代统计观点来看,这一点相当幼稚),收入分配应该有一个密度为“Ax”<sup>—“α”</sup>为“x”→∞的尾部。 |
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− | <!--- In this context using x_m for the lower bound for the scale parameter is not meaningful, usual notation is \sigma --->
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− | <!--- 在这种情况下,使用x峎m作为标度参数的下限是没有意义的,通常的符号是\sigma --->
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− | || \sigma > 0, \alpha
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| ====Pareto types I–IV帕累托分布1—4==== | | ====Pareto types I–IV帕累托分布1—4==== |
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− | |+Pareto distributions
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− | ! !! <math> \overline{F}(x)=1-F(x)</math> !! Support !! Parameters
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− | | Type I
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− | || <math>\left[\frac x \sigma \right]^{-\alpha}</math>
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− | || <math>x \ge \sigma</math>
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− | || <math>\sigma > 0, \alpha</math>
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− | | Type II
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− | || <math>\left[1 + \frac{x-\mu} \sigma \right]^{-\alpha}</math>
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− | || <math>x \ge \mu</math>
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− | || <math>\mu \in \mathbb R, \sigma > 0, \alpha</math>
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− | | Lomax
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− | || <math>\left[1 + \frac x \sigma \right]^{-\alpha}</math>
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− | || <math>x \ge 0</math>
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− | || <math>\sigma > 0, \alpha</math>
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− | | Type III
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− | || <math>\left[1 + \left(\frac{x-\mu} \sigma \right)^{1/\gamma}\right]^{-1} </math>
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− | || <math>x \ge \mu</math>
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− | || <math> \mu \in \mathbb R, \sigma, \gamma > 0</math>
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− | | Type IV
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− | || <math>\left[1 + \left(\frac{x-\mu} \sigma \right)^{1/\gamma}\right]^{-\alpha}</math>
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− | || <math>x \ge \mu</math>
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− | || <math>\mu \in \mathbb R, \sigma, \gamma > 0, \alpha</math>
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− | The shape parameter ''α'' is the [[tail index]], ''μ'' is location, ''σ'' is scale, ''γ'' is an inequality parameter. Some special cases of Pareto Type (IV) are
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− | 形状参数“α”是[[尾部索引]],“μ”是位置,“σ”是尺度,“γ”是不等式参数。帕累托类型(IV)的一些特殊情况是
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− | ::<math> P(IV)(\sigma, \sigma, 1, \alpha) = P(I)(\sigma, \alpha),</math>
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− | ::<math> P(IV)(\mu, \sigma, 1, \alpha) = P(II)(\mu, \sigma, \alpha),</math>
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− | ::<math> P(IV)(\mu, \sigma, \gamma, 1) = P(III)(\mu, \sigma, \gamma).</math>
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− | The finiteness of the mean, and the existence and the finiteness of the variance depend on the tail index ''α'' (inequality index ''γ''). In particular, fractional ''δ''-moments are finite for some ''δ'' > 0, as shown in the table below, where ''δ'' is not necessarily an integer.
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− | 均值的有限性、方差的存在性和有限性取决于尾部指数α(不等式指数γ)。特别是,对于某些“δ”>0,分数“δ”矩是有限的,如下表所示,其中“δ”不一定是整数。
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− | The Pareto distribution hierarchy is summarized in the next table comparing the [[survival function]]s (complementary CDF).
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− | 下表总结了帕累托分布层次结构,比较了[[生存函数]]s(互补CDF)。
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− | || \left[1 + \frac{x-\mu} \sigma \right]^{-\alpha}
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− | | | 左[1 + frac { x-mu } sigma right ] ^ {-alpha }
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− | When ''μ'' = 0, the Pareto distribution Type II is also known as the [[Lomax distribution]].<ref>{{cite journal | last1 = Lomax | first1 = K. S. | year = 1954 | title = Business failures. Another example of the analysis of failure data | url = | journal = Journal of the American Statistical Association | volume = 49 | issue = 268| pages = 847–52 | doi=10.1080/01621459.1954.10501239}}</ref>
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− | 当“μ”=0时,帕累托分布类型II也称为[[Lomax distribution]]。<ref>{cite journal | last1=Lomax | first1=K.S.| year=1954 | title=Business failures。另一个失败数据分析的例子| url=|journal=journal of the American Statistical Association | volume=49 | issue=268 | pages=847–52 | doi=10.1080/01621459.1954.10501239}</ref>
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− | || \mu \in \mathbb R, \sigma > 0, \alpha
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− | In this section, the symbol ''x''<sub>m</sub>, used before to indicate the minimum value of ''x'', is replaced by ''σ''.
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| 在本节中,之前用于表示“x”最小值的符号“x”<sub>m</sub>将替换为“σ”。 | | 在本节中,之前用于表示“x”最小值的符号“x”<sub>m</sub>将替换为“σ”。 |
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− | | Lomax
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− | | 洛马克斯
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− | || \left[1 + \frac x \sigma \right]^{-\alpha}
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− | [1 + frac x sigma right ] ^ {-alpha }
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− | 我们会找到他的,我们会找到他
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| |+Pareto distributions | | |+Pareto distributions |
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− | || \sigma > 0, \alpha
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− | | | sigma > 0,alpha
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| ! !! <math> \overline{F}(x)=1-F(x)</math> !! Support !! Parameters | | ! !! <math> \overline{F}(x)=1-F(x)</math> !! Support !! Parameters |
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| | Type I | | | Type I |
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− | || \left[1 + \left(\frac{x-\mu} \sigma \right)^{1/\gamma}\right]^{-1}
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− | | | 左[1 + 左(frac { x-mu } sigma 右) ^ {1/gamma }右] ^ {-1}
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| || <math>\left[\frac x \sigma \right]^{-\alpha}</math> | | || <math>\left[\frac x \sigma \right]^{-\alpha}</math> |
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− | 我们会找到他的
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| || <math>x \ge \sigma</math> | | || <math>x \ge \sigma</math> |
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− | || \mu \in \mathbb R, \sigma, \gamma > 0
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− | | | mu in mathbb r,sigma,gamma > 0
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| || <math>\sigma > 0, \alpha</math> | | || <math>\sigma > 0, \alpha</math> |
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− | | Type IV
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− | | 第 IV 类
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| | Type II | | | Type II |
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− | || \left[1 + \left(\frac{x-\mu} \sigma \right)^{1/\gamma}\right]^{-\alpha}
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− | | | 左[1 + 左(frac { x-mu } sigma 右) ^ {1/gamma }右] ^ {-alpha }
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| || <math>\left[1 + \frac{x-\mu} \sigma \right]^{-\alpha}</math> | | || <math>\left[1 + \frac{x-\mu} \sigma \right]^{-\alpha}</math> |
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− | 我们会找到他的
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| || <math>x \ge \mu</math> | | || <math>x \ge \mu</math> |
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− | || \mu \in \mathbb R, \sigma, \gamma > 0, \alpha
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− | | | mu in mathbb r,sigma,gamma > 0,alpha
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| || <math>\mu \in \mathbb R, \sigma > 0, \alpha</math> | | || <math>\mu \in \mathbb R, \sigma > 0, \alpha</math> |
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| | Lomax | | | Lomax |
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| || <math>\left[1 + \frac x \sigma \right]^{-\alpha}</math> | | || <math>\left[1 + \frac x \sigma \right]^{-\alpha}</math> |
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| || <math>x \ge 0</math> | | || <math>x \ge 0</math> |
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− | The shape parameter α is the tail index, μ is location, σ is scale, γ is an inequality parameter. Some special cases of Pareto Type (IV) are
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− | 形状参数 α 是尾部指标,μ 是位置,σ 是标度,γ 是不等式参数。帕累托型(IV)的一些特殊情况是
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| || <math>\sigma > 0, \alpha</math> | | || <math>\sigma > 0, \alpha</math> |
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− | P(IV)(\sigma, \sigma, 1, \alpha) = P(I)(\sigma, \alpha),
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− | P (IV)(sigma,sigma,1,alpha) = p (i)(sigma,alpha) ,
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| | Type III | | | Type III |
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− | P(IV)(\mu, \sigma, 1, \alpha) = P(II)(\mu, \sigma, \alpha),
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− | P(IV)(\mu, \sigma, 1, \alpha) = P(II)(\mu, \sigma, \alpha),
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| || <math>\left[1 + \left(\frac{x-\mu} \sigma \right)^{1/\gamma}\right]^{-1} </math> | | || <math>\left[1 + \left(\frac{x-\mu} \sigma \right)^{1/\gamma}\right]^{-1} </math> |
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− | P(IV)(\mu, \sigma, \gamma, 1) = P(III)(\mu, \sigma, \gamma).
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− | p (IV)(mu,sigma,gamma,1) = p (III)(mu,sigma,gamma).
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| || <math>x \ge \mu</math> | | || <math>x \ge \mu</math> |
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| || <math> \mu \in \mathbb R, \sigma, \gamma > 0</math> | | || <math> \mu \in \mathbb R, \sigma, \gamma > 0</math> |
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− | The finiteness of the mean, and the existence and the finiteness of the variance depend on the tail index α (inequality index γ). In particular, fractional δ-moments are finite for some δ > 0, as shown in the table below, where δ is not necessarily an integer.
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− | 均值的有限性、方差的存在性和有限性取决于尾指数 α (不等式指数 γ)。特别是,对于某些 δ > 0,分数阶 δ- 矩是有限的,如下表所示,其中 δ 不一定是整数。
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| | Type IV | | | Type IV |
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− | { | class = “ wikitable” border = “1”
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| || <math>\left[1 + \left(\frac{x-\mu} \sigma \right)^{1/\gamma}\right]^{-\alpha}</math> | | || <math>\left[1 + \left(\frac{x-\mu} \sigma \right)^{1/\gamma}\right]^{-\alpha}</math> |
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− | |+Moments of Pareto I–IV distributions (case μ = 0)
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− | 帕累托 i-IV 分布的 | + 矩(μ = 0)
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| || <math>x \ge \mu</math> | | || <math>x \ge \mu</math> |
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− | ! !! \operatorname{E}[X] !! Condition !! \operatorname{E}[X^\delta] !! Condition
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− | !!!操作员名称{ e }[ x ] ! !条件!操作员名称{ e }[ x ^ delta ] !环境影响评估条件
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| || <math>\mu \in \mathbb R, \sigma, \gamma > 0, \alpha</math> | | || <math>\mu \in \mathbb R, \sigma, \gamma > 0, \alpha</math> |
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− | | Type I
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− | || \frac{\sigma \alpha}{\alpha-1}
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− | | | frac { sigma alpha }{ alpha-1}
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− | || \frac{\sigma^\delta \alpha}{\alpha-\delta}
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− | | | frac { sigma ^ delta alpha }{ alpha-delta }
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| The shape parameter ''α'' is the [[tail index]], ''μ'' is location, ''σ'' is scale, ''γ'' is an inequality parameter. Some special cases of Pareto Type (IV) are | | The shape parameter ''α'' is the [[tail index]], ''μ'' is location, ''σ'' is scale, ''γ'' is an inequality parameter. Some special cases of Pareto Type (IV) are |
− | 形状参数“α”是[[尾部索引]],“μ”是位置,“σ”是尺度,“γ”是不等式参数。帕累托类型(IV)的一些特殊情况是
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− | || \delta < \alpha
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| + | 形状参数α是尾部指数tail index,μ是位置,σ是尺度,γ是不等式参数。帕累托类型(IV)的一些特殊情况有: |
| ::<math> P(IV)(\sigma, \sigma, 1, \alpha) = P(I)(\sigma, \alpha),</math> | | ::<math> P(IV)(\sigma, \sigma, 1, \alpha) = P(I)(\sigma, \alpha),</math> |
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− | | Type II
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− | | 第二类
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| ::<math> P(IV)(\mu, \sigma, 1, \alpha) = P(II)(\mu, \sigma, \alpha),</math> | | ::<math> P(IV)(\mu, \sigma, 1, \alpha) = P(II)(\mu, \sigma, \alpha),</math> |
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− | || \frac{ \sigma }{\alpha-1}
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− | | | frac { sigma }{ alpha-1}
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| ::<math> P(IV)(\mu, \sigma, \gamma, 1) = P(III)(\mu, \sigma, \gamma).</math> | | ::<math> P(IV)(\mu, \sigma, \gamma, 1) = P(III)(\mu, \sigma, \gamma).</math> |
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− | || \alpha > 1
| + | The finiteness of the mean, and the existence and the finiteness of the variance depend on the tail index ''α'' (inequality index ''γ''). In particular, fractional ''δ''-moments are finite for some ''δ'' > 0, as shown in the table below, where ''δ'' is not necessarily an integer. |
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− | || \frac{ \sigma^\delta \Gamma(\alpha-\delta)\Gamma(1+\delta)}{\Gamma(\alpha)}
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− | | | frac { sigma ^ delta Gamma (alpha-delta) Gamma (1 + delta)}{ Gamma (alpha)}
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− | The finiteness of the mean, and the existence and the finiteness of the variance depend on the tail index ''α'' (inequality index ''γ''). In particular, fractional ''δ''-moments are finite for some ''δ'' > 0, as shown in the table below, where ''δ'' is not necessarily an integer.
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| 均值的有限性、方差的存在性和有限性取决于尾部指数α(不等式指数γ)。特别是,对于某些“δ”>0,分数“δ”矩是有限的,如下表所示,其中“δ”不一定是整数。 | | 均值的有限性、方差的存在性和有限性取决于尾部指数α(不等式指数γ)。特别是,对于某些“δ”>0,分数“δ”矩是有限的,如下表所示,其中“δ”不一定是整数。 |
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− | || 0 < \delta < \alpha
| + | The Pareto distribution hierarchy is summarized in the next table comparing the [[survival function]]s (complementary CDF). |
− | | + | 下表总结了帕累托分布层次结构,比较了[[生存函数]]s(互补CDF)。 |
− | | | 0 < delta < alpha
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− | {|class="wikitable" border="1"
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− | | Type III
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− | | 第三类
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| + | {|class="wikitable" |
| |+Moments of Pareto I–IV distributions (case ''μ'' = 0) | | |+Moments of Pareto I–IV distributions (case ''μ'' = 0) |
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− | || \sigma\Gamma(1-\gamma)\Gamma(1 + \gamma)
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− | | | sigma Gamma (1-Gamma) Gamma (1 + Gamma)
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| ! !! <math>\operatorname{E}[X]</math> !! Condition !! <math>\operatorname{E}[X^\delta]</math> !! Condition | | ! !! <math>\operatorname{E}[X]</math> !! Condition !! <math>\operatorname{E}[X^\delta]</math> !! Condition |
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− | || -1<\gamma<1
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− | | |-1 < γ < 1
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− | || \sigma^\delta\Gamma(1-\gamma \delta)\Gamma(1+\gamma \delta)
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− | | | sigma ^ delta Gamma (1-Gamma delta) Gamma (1 + Gamma delta)
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| | Type I | | | Type I |
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− | || -\gamma^{-1}<\delta<\gamma^{-1}
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− | | |-gamma ^ {-1} < delta < gamma ^ {-1}
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| || <math>\frac{\sigma \alpha}{\alpha-1}</math> | | || <math>\frac{\sigma \alpha}{\alpha-1}</math> |
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| || <math>\alpha > 1</math> | | || <math>\alpha > 1</math> |
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− | | Type IV
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− | | 第 IV 类
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| || <math>\frac{\sigma^\delta \alpha}{\alpha-\delta}</math> | | || <math>\frac{\sigma^\delta \alpha}{\alpha-\delta}</math> |
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− | || \frac{\sigma\Gamma(\alpha-\gamma)\Gamma(1+\gamma)}{\Gamma(\alpha)}
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− | | | frac { sigma Gamma (alpha-Gamma) Gamma (1 + Gamma)}{ Gamma (alpha)}
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| || <math> \delta < \alpha</math> | | || <math> \delta < \alpha</math> |
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− | || -1<\gamma<\alpha
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− | | |-1 < gamma < alpha
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− | || \frac{\sigma^\delta\Gamma(\alpha-\gamma \delta)\Gamma(1+\gamma \delta)}{\Gamma(\alpha)}
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− | | | frac { sigma ^ delta Gamma (alpha-Gamma delta) Gamma (1 + Gamma delta)}{ Gamma (alpha)}
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| | Type II | | | Type II |
− | | + | || <math> \frac{ \sigma }{\alpha-1}+\mu</math> |
− | || -\gamma^{-1}<\delta<\alpha/\gamma
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− | | |-gamma ^ {-1} < delta < alpha/gamma
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− | || <math> \frac{ \sigma }{\alpha-1}</math> | |
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| || <math>\alpha > 1</math> | | || <math>\alpha > 1</math> |
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| || <math> \frac{ \sigma^\delta \Gamma(\alpha-\delta)\Gamma(1+\delta)}{\Gamma(\alpha)}</math> | | || <math> \frac{ \sigma^\delta \Gamma(\alpha-\delta)\Gamma(1+\delta)}{\Gamma(\alpha)}</math> |
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− | |}
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| || <math>0 < \delta < \alpha</math> | | || <math>0 < \delta < \alpha</math> |
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| | Type III | | | Type III |
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− | Feller
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− | 费勒
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| || <math>\sigma\Gamma(1-\gamma)\Gamma(1 + \gamma)</math> | | || <math>\sigma\Gamma(1-\gamma)\Gamma(1 + \gamma)</math> |
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| || <math> -1<\gamma<1</math> | | || <math> -1<\gamma<1</math> |
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− | W = \mu + \sigma \left(\frac{U_1}{U_2}\right)^\gamma
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− | W = mu + sigma left (frac { u _ 1}{ u _ 2} right) ^ gamma
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| || <math>\sigma^\delta\Gamma(1-\gamma \delta)\Gamma(1+\gamma \delta)</math> | | || <math>\sigma^\delta\Gamma(1-\gamma \delta)\Gamma(1+\gamma \delta)</math> |
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| || <math>-\gamma^{-1}<\delta<\gamma^{-1}</math> | | || <math>-\gamma^{-1}<\delta<\gamma^{-1}</math> |
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− | and we write W ~ FP(μ, σ, γ, δ1, δ2). Special cases of the Feller–Pareto distribution are
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− | 写出 w ~ FP (μ,σ,γ,δ1,δ2)。帕累托分布的特殊情况如下
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| | Type IV | | | Type IV |
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− | FP(\sigma, \sigma, 1, 1, \alpha) = P(I)(\sigma, \alpha)
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− | FP (sigma,sigma,1,1,alpha) = p (i)(sigma,alpha)
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| || <math>\frac{\sigma\Gamma(\alpha-\gamma)\Gamma(1+\gamma)}{\Gamma(\alpha)}</math> | | || <math>\frac{\sigma\Gamma(\alpha-\gamma)\Gamma(1+\gamma)}{\Gamma(\alpha)}</math> |
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− | FP(\mu, \sigma, 1, 1, \alpha) = P(II)(\mu, \sigma, \alpha)
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− | FP (mu,sigma,1,1,alpha) = p (II)(mu,sigma,alpha)
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| || <math> -1<\gamma<\alpha</math> | | || <math> -1<\gamma<\alpha</math> |
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− | FP(\mu, \sigma, \gamma, 1, 1) = P(III)(\mu, \sigma, \gamma)
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− | FP (mu,sigma,gamma,1,1) = p (III)(mu,sigma,gamma)
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| || <math>\frac{\sigma^\delta\Gamma(\alpha-\gamma \delta)\Gamma(1+\gamma \delta)}{\Gamma(\alpha)}</math> | | || <math>\frac{\sigma^\delta\Gamma(\alpha-\gamma \delta)\Gamma(1+\gamma \delta)}{\Gamma(\alpha)}</math> |
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− | FP(\mu, \sigma, \gamma, 1, \alpha) = P(IV)(\mu, \sigma, \gamma, \alpha).
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− | FP (mu,sigma,gamma,1,alpha) = p (IV)(mu,sigma,gamma,alpha).
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| || <math>-\gamma^{-1}<\delta<\alpha/\gamma </math> | | || <math>-\gamma^{-1}<\delta<\alpha/\gamma </math> |
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− | The Pareto distribution is related to the exponential distribution as follows. If X is Pareto-distributed with minimum xm and index α, then
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− | 美国帕累托分布协会与美国指数分布协会有如下关系。如果 x 是以最小 xm 和指数 α 为参数的 pareto 分布,则
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| |} | | |} |
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− | Y = \log\left(\frac{X}{x_\mathrm{m}}\right)
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− | Y = log left (frac { x }{ x _ mathrm { m } right)
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| ====Feller–Pareto distribution费勒-帕累托分布==== | | ====Feller–Pareto distribution费勒-帕累托分布==== |
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| Feller<ref name=jkb94/><ref name=feller/> defines a Pareto variable by transformation ''U'' = ''Y''<sup>−1</sup> − 1 of a [[beta distribution|beta random variable]] ''Y'', whose probability density function is | | Feller<ref name=jkb94/><ref name=feller/> defines a Pareto variable by transformation ''U'' = ''Y''<sup>−1</sup> − 1 of a [[beta distribution|beta random variable]] ''Y'', whose probability density function is |
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− | 费勒Feller<ref name=jkb94/><ref name=Feller/>通过[[β分布|β随机变量]] ''Y''的转换''U'' = ''Y''<sup>−1</sup> − 1 定义一个Pareto变量,其概率密度函数为 | + | '''费勒Feller'''<ref name=jkb94/><ref name=Feller/>通过[[β分布|β随机变量]] ''Y''的转换''U'' = ''Y''<sup>−1</sup> − 1 定义一个Pareto变量,其概率密度函数为 |
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| is exponentially distributed with rate parameter α. Equivalently, if Y is exponentially distributed with rate α, then | | is exponentially distributed with rate parameter α. Equivalently, if Y is exponentially distributed with rate α, then |
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| 与速率参数α呈指数分布。等价地,如果Y与速率α呈指数分布,则 | | 与速率参数α呈指数分布。等价地,如果Y与速率α呈指数分布,则 |
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| :<math> f(y) = \frac{y^{\gamma_1-1} (1-y)^{\gamma_2-1}}{B(\gamma_1, \gamma_2)}, \qquad 0<y<1; \gamma_1,\gamma_2>0,</math> | | :<math> f(y) = \frac{y^{\gamma_1-1} (1-y)^{\gamma_2-1}}{B(\gamma_1, \gamma_2)}, \qquad 0<y<1; \gamma_1,\gamma_2>0,</math> |
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− | x_\mathrm{m} e^Y
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− | 2. x mathrm { m } e ^ y
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| where ''B''( ) is the [[beta function]]. If | | where ''B''( ) is the [[beta function]]. If |
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| This can be shown using the standard change-of-variable techniques: | | This can be shown using the standard change-of-variable techniques: |
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− | 这可以使用标准的变量更改技术来显示:
| + | 使用标准的变量更改技术来显示: |
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