wle.cv(wle)
wle.cv()所属R语言包:wle
Model Selection by Weighted Cross-Validation
选型的加权交叉验证
译者:生物统计家园网 机器人LoveR
描述----------Description----------
The Weighted Cross-Validation methods is used to choose
的加权交叉验证的方法是用来选择
用法----------Usage----------
wle.cv(formula, data=list(), model=TRUE, x=FALSE,
y=FALSE, monte.carlo=500, split, boot=30,
group, num.sol=1, raf="HD", smooth=0.031,
tol=10^(-6), equal=10^(-3), max.iter=500,
参数----------Arguments----------
参数:formula
a symbolic description of the model to be fit. The details of model specification are given below.
一个象征性的模型来描述是合适的。模型规范的细节在下面给出。
参数:data
an optional data frame containing the variables in the model. By default the variables are taken from the environment which wle.cv is called from.
一个可选的数据框包含在模型中的变量。默认情况下,变量是从wle.cv被称为从环境。
参数:model, x, y
logicals. If TRUE the corresponding components of the fit (the model frame, the model matrix, the response.)
的逻辑。如果TRUE拟合的相应部件(模型框架,模型矩阵,响应。)
参数:monte.carlo
the number of Monte Carlo replication we use to estimate the average prediction error.
我们估计的平均预测误差的蒙特卡罗复制。
参数:split
the size of the costruction sample. When the suggested value is outside the possible range, the split size is let equal to max(round(size^{(3/4)}),var+2) where size is the number of observations and var is the number of variables.
施工,样品的大小。建议值的可能范围外时,分割大小等于max(round(size^{(3/4)}),var+2)其中size的一些意见和var是变量的数目。
参数:boot
the number of starting points based on boostrap subsamples to use in the search of the roots.
基于自举子样本的起点,使用在搜索的根的数目。
参数:group
the dimension of the bootstap subsamples. The default value is max(round(size/4),var) where size is the number of observations and var is the number of variables.
的维度的bootstap子样本。默认值是max(round(size/4),var)size的一些意见和var是变量的数目。
参数:num.sol
maximum number of roots to be searched.
要搜索的最大根数。
参数:raf
type of Residual adjustment function to be use:
类型的残余调节功能,可以使用:
raf="HD": Hellinger Distance RAF,
raf="HD":Hellinger距离RAF,
raf="NED": Negative Exponential Disparity RAF,
raf="NED":负指数差异RAF,
raf="SCHI2": Symmetric Chi-Squared Disparity RAF.
raf="SCHI2":对称卡方差异皇家空军。
参数:smooth
the value of the smoothing parameter.
的平滑化参数的值。
参数:tol
the absolute accuracy to be used to achieve convergence of the algorithm.
要使用的绝对精度实现算法的收敛性。
参数:equal
the absolute value for which two roots are considered the same. (This parameter must be greater than tol).
绝对的值,两个根被认为是相同的。 (此参数必须大于tol)。
参数:max.iter
maximum number of iterations.
最大迭代次数。
参数:min.weight
see details.
查看详细信息。
参数:contrasts
an optional list. See the contrasts.arg of model.matrix.default.
可选列表。请参阅contrasts.argmodel.matrix.default。
参数:verbose
if TRUE warnings are printed.
如果TRUE警告被打印出来。
Details
详细信息----------Details----------
Models for wle.cv are specified symbolically. A typical model has the form response ~ terms where response is the (numeric) response vector and terms is a series of terms which specifies a linear predictor for response. A terms specification of the form first+second indicates all the terms in first together with all the terms in second with duplicates removed. A specification of the form first:second indicates the the set of terms obtained by taking the interactions of all terms in first with all terms in second. The specification first*second indicates the cross of first and second. This is the same as first+second+first:second.
模型wle.cv的符号。典型的模型形式response ~ terms其中response是响应向量(数字)和terms是一系列的条款,指定一个线性预测response。一个术语规范的形式first+second表示first一起在second重复删除的所有条款中的所有条款。一个规范的形式first:second的表示的术语集firstsecond的所有条款的相互作用的所有条款。规格first*second表明first和second交叉的。这是相同first+second+first:second。
值----------Value----------
wle.cv returns an object of class "wle.cv".
wle.cv返回一个对象的class"wle.cv"的。
The function summary is used to obtain and print a summary of the results. The generic accessor functions coefficients and residuals extract coefficients and residuals returned by wle.cv. The object returned by wle.cv are:
函数summary用于获取和打印结果的摘要。一般的访问功能coefficients和residuals的提取系数和残差返回wle.cv。对象返回wle.cv是:
<table summary="R valueblock"> <tr valign="top"><td>wcv</td> <td> Weighted Cross-Validation for each submodels</td></tr> <tr valign="top"><td>coefficients</td> <td> the parameters estimator, one row vector for each root found in the full model.</td></tr> <tr valign="top"><td>scale</td> <td> an estimation of the error scale, one value for each root found in the full model.</td></tr> <tr valign="top"><td>residuals</td> <td> the unweighted residuals from the estimated model, one column vector for each root found in the full model.</td></tr> <tr valign="top"><td>tot.weights</td> <td> the sum of the weights divide by the number of observations, one value for each root found in the full model.</td></tr> <tr valign="top"><td>weights</td> <td> the weights associated to each observation, one column vector for each root found in the full model.</td></tr> <tr valign="top"><td>freq</td> <td> the number of starting points converging to the roots.</td></tr> <tr valign="top"><td>index</td> <td> position of the root used for the weights.</td></tr> <tr valign="top"><td>call</td> <td> the match.call().</td></tr> <tr valign="top"><td>contrasts</td> <td> </td></tr> <tr valign="top"><td>xlevels</td> <td> </td></tr> <tr valign="top"><td>terms</td> <td> the model frame.</td></tr> <tr valign="top"><td>model</td> <td> if model=TRUE a matrix with first column the dependent variable and the remain column the explanatory variables for the full model.</td></tr> <tr valign="top"><td>x</td> <td> if x=TRUE a matrix with the explanatory variables for the full model.</td></tr> <tr valign="top"><td>y</td> <td> if y=TRUE a vector with the dependent variable.</td></tr> <tr valign="top"><td>info</td> <td> not well working yet, if 0 no error occurred.</td></tr> </table>
<table summary="R valueblock"> <tr valign="top"> <TD> wcv</ TD> <TD>各子模型的加权交叉验证</ TD> </ TR> <TR VALIGN =“”> <TD>coefficients </ TD> <TD>的参数估计,每一根完整的模型中发现一个行向量。</ TD> </ TR> <TR VALIGN =“顶部“> <TD> scale </ TD> <TD>的错误规模估计,每一根完整的模型中发现的一个值。</ TD> </ TR> <TR VALIGN =”顶“ > <TD> residuals </ TD> <TD>未加权的估计模型的残差,每一根完整的模型中发现一个列向量。</ TD> </ TR> <TR VALIGN =“顶部“> <TD> tot.weights </ TD> <TD>的权重总和除以观测值的数量,每一根完整的模型中发现的一个值。</ TD> </ TR> <TR VALIGN =“”> <TD>weights </ TD> <TD>相关的权重给每个观察每一根完整的模型中发现,一个列向量。</ TD> </ TR> <TR VALIGN =“”> <TD>freq </ TD> <TD>收敛的根源出发点的数量。</ TD> </ TR> <tr valign="top"> <TD> index</ TD> <TD>的权重根的位置。</ TD> </ TR> <tr valign="top"> <TD> call </ TD> < TD> match.call()</ TD> </ TR> <tr valign="top"> <TD>contrasts </ TD> <TD> </ TD> </ TR> <TR VALIGN =“”> <TD>xlevels </ TD> <TD> </ TD> </ TR> <tr valign="top"> <TD> terms</ TD> < TD>的模型框架。</ TD> </ TR> <tr valign="top"> <TD> model </ TD> <TD>如果model=TRUE矩阵第一列的依赖变量和列的是整个模型的解释变量。</ TD> </ TR> <tr valign="top"> <TD>x </ TD> <td>如果x=TRUE一个完整的模型的解释变量的矩阵。</ TD> </ TR> <tr valign="top"> <TD> y</ TD> <TD>如果y=TRUE矢量与因变量。</ TD> </ TR> <tr valign="top"> <TD>info </ TD> <TD>还不能很好地工作,如果没有错误发生。</ TD > </ TR> </ TABLE>
(作者)----------Author(s)----------
Claudio Agostinelli
参考文献----------References----------
Agostinelli, C., (1999). Robust model selection by Cross-Validation via weighted likelihood methodology, Working Paper n. 1999.37, Department of Statistics, University of Padova.
Agostinelli, C., (1998). Inferenza statistica robusta basata sulla funzione di verosimiglianza pesata: alcuni sviluppi, Ph.D Thesis, Department of Statistics, University of Padova.
Agostinelli, C., Markatou, M., (1998). A one-step robust estimator for regression based on the weighted likelihood reweighting scheme, Statistics \& Probability Letters, Vol. 37, n. 4, 341-350.
Agostinelli, C., (1998). Verosimiglianza pesata nel modello di regressione lineare, XXXIX Riunione scientifica della Societ\'a Italiana di Statistica, Sorrento 1998.
参见----------See Also----------
wle.smooth an algorithm to choose the smoothing parameter for normal distribution and normal kernel, wle.lm a function for estimating linear models with normal distribution error and normal kernel.
wle.smooth算法选择平滑参数正常分布和正态分布的内核,wle.lm估计线性模型与正常分配错误和正常的内核的功能。
实例----------Examples----------
library(wle)
set.seed(1234)
x.data <- c(runif(60,20,80),runif(5,73,78))
e.data <- rnorm(65,0,0.6)
y.data <- 8*log(x.data+1)+e.data
y.data[61:65] <- y.data[61:65]-4
z.data <- c(rep(0,60),rep(1,5))
plot(x.data,y.data,xlab="X",ylab="Y")
xx.data <- cbind(x.data,x.data^2,x.data^3,log(x.data+1))
colnames(xx.data) <- c("X","X^2","X^3","log(X+1)")
result <- wle.cv(y.data~xx.data,boot=20,num.sol=2)
summary(result)
result <- wle.cv(y.data~xx.data+z.data,boot=20,num.sol=2,
monte.carlo=1000,split=50)
summary(result)
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