Question

我从Brett Lantz的教科书“Machine Learning With R”中取出了以下代码，但是从教科书中将其完全复制到控制台，

Route::auth();


Route::group(['middleware' => 'auth'], function () {
    Route::post('entity/process', 'EntityController@process');
    Route::get('entity/form/{subCategoryID}/{id?}', 'EntityController@viewForm');
    Route::get('entity/delete/{id}', 'EntityController@delete');
    Route::get('/viewList/{masterCategoryID}/{subCategoryID}', 'EntityController@viewList');
    Route::get('/viewCategories', 'MasterCategoryController@viewAll');

  Route::get('/', 'MasterCategoryController@viewAll');
});

我收到了这个回复。怎么了？

> library(caret)
Loading required package: lattice
Loading required package: ggplot2
> library(kernlab)

Attaching package: ‘kernlab’

The following object is masked from ‘package:ggplot2’:

alpha

> set.seed(300)
> ctrl <- trainControl(method = "cv", number = 10)
> bagctrl <- bagControl(fit = svmBag$fit, predict = svmBag$pred, aggregate = svmBag$aggregate)
> setwd("~/2148OS_code/chapter 11")
> credit <- read.csv("credit.csv")
> svmbag <- train(default ~ ., data = credit, "bag", trControl = ctrl, bagControl = bagctrl)

警告是

Something is wrong; all the Accuracy metric values are missing:
    Accuracy       Kappa    
 Min.   : NA   Min.   : NA  
 1st Qu.: NA   1st Qu.: NA  
 Median : NA   Median : NA  
 Mean   :NaN   Mean   :NaN  
 3rd Qu.: NA   3rd Qu.: NA  
 Max.   : NA   Max.   : NA  
 NA's   :1     NA's   :1    
Error in train.default(x, y, weights = w, ...) : Stopping
In addition: There were 50 or more warnings (use warnings() to see the first 50)

Answer 1

之前我遇到过同样的问题。问题出现在类变量值中。

请尝试将类值从“0”，“1”更改为例如“A”，“B”并尝试相同的代码。

Answer 2

我使用了第二版打包提供的代码。

如果设置并行处理，警告将消失。您仍然会得到缺少准确度指标的错误。

此错误是由重采样性能度量中缺少值的事实引起的。如果存在重新采样，其中一个结果类（在这种情况下是默认值）的样本为零，那么可能会发生这种情况，因此未定义敏感性或特异性。

我还使用插入符包中包含的GermanCredit数据运行测试，这会产生相同的错误。

“出了点问题;所有准确度指标值都丢失了：”

2 个答案: