matlab帕累托分布函数,matlab 进行广义的帕累托参数估计

本文介绍了如何在MATLAB中使用gpfit函数进行广义帕累托分布的参数估计。通过gpfit函数,可以获取尾部指数(形状)参数和尺度参数的最大似然估计值,并可计算置信区间。当尾部指数为0且阈值为0时,分布等价于指数分布;当尾部指数大于0且阈值等于尺度参数时,等价于帕累托分布。注意,gpfit函数不估计阈值参数,需要预先处理数据。

还是给你回答了吧

parmhat = gpfit(X) 产生pareto随机数

参数估计,

[parmhat,parmci] = gpfit(X)

参数估计,有alpha

[parmhat,parmci] = gpfit(X,alpha)

GPFIT Parameter estimates and confidence intervals for generalized Pareto data.

PARMHAT = GPFIT(X) returns maximum likelihood estimates of the parameters

of the two-parameter generalized Pareto (GP) distribution given the data

in X.  PARMHAT(1) is the tail index (shape) parameter, K and PARMHAT(2) is

the scale parameter, SIGMA.  GPFIT does not fit a threshold (location)

parameter.

[PARMHAT,PARMCI] = GPFIT(X) returns 95% confidence intervals for the

parameter estimates.

[PARMHAT,PARMCI] = GPFIT(X,ALPHA) returns 100(1-ALPHA) percent confidence

intervals for the parameter estimates.

[...] = GPFIT(X,ALPHA,OPTIONS) specifies control parameters for the

iterative algorithm used to compute ML estimates. This argument can be

created by a call to STATSET.  See STATSET('gpfit') for parameter names

and default values.

Pass in [] for ALPHA to use the default values.

Other functions for the generalized Pareto, such as GPCDF, allow a

threshold parameter THETA.  However, GPFIT does not estimate THETA, and it

must be assumed known, and subtracted from X before calling GPFIT.

When K = 0 and THETA = 0, the GP is equivalent to the exponential

distribution.  When K > 0 and THETA = SIGMA, the GP is equivalent to the

Pareto distribution. The mean of the GP is not finite when K >= 1, and the

variance is not finite when K >= 1/2.  When K >= 0, the GP has positive

density for X>THETA, or, when K < 0, for 0 <= (X-THETA)/SIGMA <= -1/K.

评论
成就一亿技术人!
拼手气红包6.0元
还能输入1000个字符  | 博主筛选后可见
 
红包 添加红包
表情包 插入表情
 条评论被折叠 查看
添加红包

请填写红包祝福语或标题

红包个数最小为10个

红包金额最低5元

当前余额3.43前往充值 >
需支付:10.00
成就一亿技术人!
领取后你会自动成为博主和红包主的粉丝 规则
hope_wisdom
发出的红包
实付
使用余额支付
点击重新获取
扫码支付
钱包余额 0

抵扣说明:

1.余额是钱包充值的虚拟货币,按照1:1的比例进行支付金额的抵扣。
2.余额无法直接购买下载,可以购买VIP、付费专栏及课程。

余额充值