我该如何将下面的命令列表写成一个函数?
例如:VariableRanking <- function(formula, variables,.....) { 插入命令........ }
例如:VariableRanking <- function(formula, variables,.....) { 插入命令........ }
#Variable Ranking Model automation
#exclusion of the variables that are not model variables
exclude <- c("~,", "+" ) # exclude target which is bound_count for Property
formula <- toString(formula)
formula
#listing the entire model formula out
variables_pre <- unlist(strsplit(formula, split = " "))
variables_pre
#keeping only the model variables
variables <- sort(variables_pre[!variables_pre %in% exclude])
variables
#Exclude "," on the target variable
variables[1] <- substr(variables[1], 1, nchar(variables[1])-1)
variables
#Assigning the variables into a data frame
d <- c(1:length(variables))
d
d= data.frame(d)
d
d= t(d)
d
colnames(d)=variables
d
# exclude target variable on the data frame
allvariables <- colnames(d)[-1]
allvariables
# container for models
listOfModels <- vector("list", length(allvariables))
listOfModels
# loop over variables
for (i in seq_along(allvariables)) {
# exclude variable i
currentvariable <- allvariables[-i]
# programmatically assemble regression formula
regressionFormula <- as.formula(
paste(variables[1],"~", paste(currentvariable, collapse="+")))
# fit model
currentModel <- glm(formula = regressionFormula, family=binomial(link = "logit"), data=dataL_TT)
# store model in container
listOfModels[[i]] <- currentModel
}
listOfModels
#List of AICs for each model
lapply(listOfModels,function(xx) xx$aic)
#Assign X as the AIC of the full model
X <- modelTT$aic
X
# Difference of AICs of each model to the AIC of the full model
AICdifference <- lapply(listOfModels,function(xx) xx$aic - X)
AICdifference
# Naming the AIC Difference
AICdifference2 = data.frame(variables=allvariables, AICdiff=unlist(AICdifference))
AICdifference2
#Graph the Barchart of the AIC decrease of each variables and save it to pdf
pdf("Barchart.pdf",width=12,height=10)
par(mar=c(2,18,2,5))
barplot(sort(AICdifference2$AICdiff, decreasing = F), main="Variable Ranking based on AIC decrease",
horiz=TRUE, xlab="AIC Increase", names.arg= AICdifference2$variables[order(AICdifference2$AICdiff, decreasing = F)],
las=1, col= 'dodgerblue4')
dev.off()
有可能吗?因为它有很多参数。 基本上我只需要AICdifference2数据框的输出。 以及将条形图保存为pdf并弹出。
exclude
、formula
和data_LTT
。最好展示一个小的可重现的例子。 - akrunformula
、data_LTT
和modelTT
。 - LAP