rpart.control(rpart)
rpart.control()所属R语言包：rpart
Control for Rpart Models
控制软件rpart模型
译者：生物统计家园网 机器人LoveR
描述----------Description----------
Various parameters that control aspects of the rpart fit.
rpart适合的控制方面的各种参数。
用法----------Usage----------
rpart.control(minsplit = 20, minbucket = round(minsplit/3), cp = 0.01,
maxcompete = 4, maxsurrogate = 5, usesurrogate = 2, xval = 10,
surrogatestyle = 0, maxdepth = 30, ...)
参数----------Arguments----------
参数：minsplit
the minimum number of observations that must exist in a node in order for a split to be attempted.
在为一个企图分裂节点的意见，即必须存在的最小数量。
参数：minbucket
the minimum number of observations in any terminal <leaf> node. If only one of minbucket or minsplit is specified, the code either sets minsplit to minbucket*3 or minbucket to minsplit/3, as appropriate.
在任何终端<leaf>节点的最小数目的观测。如果只有一个minbucket或minsplit指定，代码设置minsplitminbucket*3或minbucketminsplit/3，适当。
参数：cp
complexity parameter. Any split that does not decrease the overall lack of fit by a factor of cp is not attempted. For instance, with anova splitting, this means that the overall Rsquare must increase by cp at each step. The main role of this parameter is to save computing time by pruning off splits that are obviously not worthwhile. Essentially,the user informs the program that any split which does not improve the fit by cp will likely be pruned off by cross-validation, and that hence the program need not pursue it.
复杂的参数。任何分裂不会降低整体上缺乏合适由cp因素的没有尝试。例如，anova分裂，这意味着整体Rsquare必须增加cp的每一步。此参数的主要作用是为了节省计算时间，通过修剪过分裂，显然是不值得。从本质上讲，用户通知程序不改善适合任何分裂cp可能会被修剪交叉验证，并因此程序需要不追求它。
参数：maxcompete
the number of competitor splits retained in the output. It is useful to know not just which split was chosen, but which variable came in second, third, etc.
竞争对手的数量分割保留在输出。知道被选为不仅仅是分裂，它是有用的，但变量在第二，第三等
参数：maxsurrogate
the number of surrogate splits retained in the output. If this is set to zero the compute time will be reduced, since approximately half of the computational time (other than setup) is used in the search for surrogate splits.
代理的数量分割保留在输出。如果设置为零的计算时间将会减少，因为大约一半的计算时间（安装除外），在寻找替代分裂，。
参数：usesurrogate
how to use surrogates in the splitting process. 0 means display only; an observation with a missing value for the primary split rule is not sent further down the tree. 1 means use surrogates, in order, to split subjects missing the primary variable; if all surrogates are missing the observation is not split. For value 2 ,if all surrogates are missing, then send the observation in the majority direction. A value of 0 corresponds to the action of tree, and 2 to the recommendations of Breiman et.al.
如何在分裂过程中使用的代理人。 0意味着只显示一个主分割规则的缺失值的观察进一步不派下来的树。 1意味着使用代理人，为了分裂科目缺少的主要变量，不分裂，如果所有的代理人都缺少观察。值2，如果所有的代理人失踪，然后发送在大多数方向的观察。值的0对应行动tree，2布雷曼博士的建议et.al.
参数：xval
number of cross-validations.
交叉验证的数量。
参数：surrogatestyle
controls the selection of a best surrogate. If set to 0 (default) the program uses the total number of correct classification for a potential surrogate variable, if set to 1 it uses the percent correct, calculated over the non-missing values of the surrogate. The first option more severely penalizes covariates with a large number of missing values.
控制的最佳替代选择。如果设置为0（默认）计划使用一个潜在的替代变量的正确分类的总数，如果设置为1它使用正确的百分比计算，代理非缺失值超过。第一个选项更严厉的惩罚与大量缺失值的协变量。
参数：maxdepth
Set the maximum depth of any node of the final tree, with the root node counted as depth 0. Values greater than 30 rpart will give nonsense results on 32-bit machines.
设置的任何最终的树节点的最大深度，根节点深度为0计算。值大于30rpart给32位机器上无意义的结果。
参数：...
mop up other arguments.
扫荡其他参数。
值----------Value----------
A list containing the options.
一个列表，其中包含的选项。
参见----------See Also----------
rpart
rpart
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。
|
发表于 2012-2-16 18:43:33
