Question

我正在尝试使用Shiny应用程序并发现下面的代码可以正常工作。

ui.R：

data(Titanic)
head(as.data.frame(Titanic),5)
library(shiny)
shinyUI(pageWithSidebar(
  headerPanel("Titanic Survival Calculator"),
  sidebarPanel(
    p("Select person attributes to calculate his/her chances of surviving of 
the titanic sinking."),
    selectInput("c", label =h3("Crew/Passenger:"), list("1st Class Passenger" = "1st","2nd Class Passenger" = "2nd", "3rd Class Passenger" = "3rd", "Crew Member" = "Crew")),
radioButtons("s", label = h3("Sex:"),
             choices = list("Male" = "Male", "Female" = "Female"), 
             selected = "Female"),
radioButtons("a", label = h3("Age:"),
             choices = list("Child" = "Child", "Adult" = "Adult"),
             selected = "Adult")),
  mainPanel(
h3("Survival Probability:"),
h4(textOutput('prob')),
p("Please note that this is estimated probability based on a logistic regression model."),
p("That means this value is slightly different than historical survival rate."))))

server.R：

library(shiny)
library(datasets)
data(Titanic)
tit <- as.data.frame(Titanic)
tit_glm <- glm(Survived ~ Class + Sex + Age, binomial, tit, tit$Freq)

pred_tit <- function(class, sex, age ){
  inputdata <- c(class, sex, age)
  pred_data <- as.data.frame(t(inputdata))
  colnames(pred_data) <- c("Class", "Sex", "Age")
  surv_prob <- predict(tit_glm,pred_data , type = "response" )
  return(surv_prob)
}

shinyServer(
  function(input, output) {
output$prob <- renderText({pred_tit(input$c,input$s, input$a)})
  })

但是，我想使用Randomforest模型而不是GLM。我尝试通过输入简单代码

来使用randomforest

tit_glm <- randomForest(Survived ~ ., tit)

但我一直收到错误消息。请有人帮帮我吗？

Answer 1

tit_glm <- randomForest(Survived ~ ., tit)

会出错，因为这意味着您正在使用所有其他功能进行模型培训。然而，这是不可能的，因为有很多特征主要是NA，并且有一些特征几乎没有方差。

首先尝试删除大部分为NA的功能，然后删除近零方差功能。

Shiny R randomForest错误

1 个答案: