mle.stepwise(wle)
mle.stepwise()所属R语言包:wle
Stepwise, Backward and Forward selection methods
逐步,向后和向前的选择方法
译者:生物统计家园网 机器人LoveR
描述----------Description----------
This function performs Stepwise, Forward and Backward model selection.
此功能进行逐步,前进和后退的模式选择。
----------Usage----------
mle.stepwise(formula, data=list(), model=TRUE, x=FALSE,
y=FALSE, type="Forward", f.in=4.0, f.out=4.0,
contransts=NULL, verbose=FALSE)
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 mle.stepwise 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mle.stepwise被称为从从环境。
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:type
type="Stepwise": the stepwise methods is used,
type="Stepwise":逐步的方法,用于
type="Forward": the forward methods is used,
type="Forward":forward方法被使用时,
type="Backward": the backward method is used.
type="Backward":使用落后的方法。
参数:f.in
the in value
价值
参数:f.out
the out value
超时值
参数:contransts
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 mle.stepwise 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mle.stepwise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----------
mle.stepwise returns an object of class "mle.stepwise".
mle.stepwise返回一个对象的class"mle.stepwise"的。
The function summary is used to obtain and print a summary of the results.
函数summary用于获取和打印结果的摘要。
The object returned by mle.stepwise are:
对象返回mle.stepwise是:
<table summary="R valueblock"> <tr valign="top"><td>step</td> <td> the selected models</td></tr> <tr valign="top"><td>type</td> <td> the type o model selection procedure was used.</td></tr> <tr valign="top"><td>f.in</td> <td> the value of f.in used.</td></tr> <tr valign="top"><td>f.out</td> <td> the value of f.out used.</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> step</ TD> <TD>选定的模型</ TD> </ TR> <TR VALIGN =“顶” > <TD> type </ TD> <TD> O型模型的选择过程。</ TD> </ TR> <tr valign="top"> <TD>f.in / TD <TD> f.in使用/ TD / TR> <tr valign="top"> <TD>f.out/ <TD> f值出来。</ TD> </ TR> <tr valign="top"> <TD>call </ TD> <TD> match.call()。</ TD> </ TR> < TR VALIGN =“顶”> <TD>contrasts </ TD> <TD> </ TD> </ TR> <tr valign="top"> <TD> xlevels </ TD> <TD> </ TD> </ TR> <tr valign="top"> <TD>terms</ TD> <TD>模型框架。</ TD> </ TR> <TR VALIGN = “顶”> <TD> model </ TD> <TD> model=TRUE第一列因变量和列的完整模型的解释变量矩阵。</ TD> < / TR> <tr valign="top"> <TD> x </ TD> <TD>如果x=TRUE完整的模型的解释变量矩阵。</ TD> </ TR > <tr valign="top"> <TD> y </ TD> <TD>如果y=TRUE与因变量的向量。</ TD> </ TR> <TR VALIGN =“顶“<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----------
Beale, E.M.L., Kendall, M.G., Mann, D.W., (1967) The discarding of variables in multivariate analysis, Biometrika, 54, 357-366.
Efroymson, (1960) Multiple regression analysis, in Mathematical Methods for Digital Computers, eds. A. Ralston and H.S. Wilf, 191-203, Wiley, New York.
Garside, M.J., (1965) The best sub-set in multiple regression analysis, Applied Statistics, 14, 196-200.
Goldberger, A.S, and Jochems, D.B., (1961) Note on stepwise least squares, Journal of the American Statistical Association, 56, 105-110.
Goldberger, A.S., (1961) Stepwise least squares: Residual analysis and specification error, Journal of the American Statistical Association, 56, 998-1000.
实例----------Examples----------
library(wle)
data(hald)
cor(hald)
result <- mle.stepwise(y.hald~x.hald)
summary(result)
转载请注明:出自 生物统计家园网(http://www.biostatistic.net)。
注:
注1:为了方便大家学习,本文档为生物统计家园网机器人LoveR翻译而成,仅供个人R语言学习参考使用,生物统计家园保留版权。
注2:由于是机器人自动翻译,难免有不准确之处,使用时仔细对照中、英文内容进行反复理解,可以帮助R语言的学习。
注3:如遇到不准确之处,请在本贴的后面进行回帖,我们会逐渐进行修订。
|