在运行以下R代码时:library(glmnet) library(ggplot2) # 生成5030的随机数据和30个变量 set.seed(1111) n <- 50 p <- 30 X <- matrix(runif(n * p), n, p) y <- rnorm(n) # 生成三组不同系数的线性模型 beta1 <- c(rep(1, 3), rep(0, p - 3)) beta2 <- c(rep(0, 10), rep(1, 3), rep(0, p - 13)) beta3 <- c(rep(0, 20), rep(1, 3), rep(0, p - 23)) y1 <- X %% beta1 + rnorm(n) y2 <- X %% beta2 + rnorm(n) y3 <- X %% beta3 + rnorm(n) # 设置交叉验证折数 k <- 10 # 设置不同的lambda值 lambda_seq <- 10^seq(10, -2, length.out = 100) # 执行交叉验证和岭回归,并记录CV error和Prediction error cv_error <- list() pred_error <- list() for (i in 1:3) { # 交叉验证 cvfit <- cv.glmnet(X, switch(i, y1, y2, y3), alpha = 0, lambda = lambda_seq, nfolds = k) cv_error[[i]] <- cvfit$cvm # 岭回归 fit <- glmnet(X, switch(i, y1, y2, y3), alpha = 0, lambda = lambda_seq) pred_error[[i]] <- apply(X, 2, function(x) { x_mat <- matrix(x, nrow = n, ncol = p, byrow = TRUE) pred <- predict(fit, newx = x_mat) pred <- t(pred) # 转置 mean((x_mat %% fit$beta - switch(i, y1, y2, y3))^2, na.rm = TRUE) # 修改此处 }) } # 绘制图形 par(mfrow = c(3, 2), mar = c(4, 4, 2, 1), oma = c(0, 0, 2, 0)) for (i in 1:3) { # CV error plot cv_plot_data <- cv_error[[i]] plot(log10(lambda_seq), cv_plot_data, type = "l", xlab = expression(log10), ylab = "CV error", main = paste0("Model ", i)) abline(v = log10(cvfit$lambda.min), col = "red") # Prediction error plot pred_plot_data <- pred_error[[i]] plot(log10(lambda_seq), pred_plot_data, type = "l", xlab = expression(log10), ylab = "Prediction error", main = paste0("Model ", i)) abline(v = log10(lambda_seq[which.min(pred_plot_data)]), col = "red") }。发生以下错误:Error in h(simpleError(msg, call)) : 在为'mean'函数选择方法时评估'x'参数出了错: non-conformable arguments 。请对原代码进行修正
时间: 2023-09-22 17:06:40 浏览: 152
一个简单的R语言数据分析案例.pdf
这段代码中有一个问题,即在计算预测误差时,矩阵相乘的维度不匹配,需要进行修正。以下是修正后的代码:
```r
library(glmnet)
library(ggplot2)
# 生成5030的随机数据和30个变量
set.seed(1111)
n <- 50
p <- 30
X <- matrix(runif(n * p), n, p)
y <- rnorm(n)
# 生成三组不同系数的线性模型
beta1 <- c(rep(1, 3), rep(0, p - 3))
beta2 <- c(rep(0, 10), rep(1, 3), rep(0, p - 13))
beta3 <- c(rep(0, 20), rep(1, 3), rep(0, p - 23))
y1 <- X %*% beta1 + rnorm(n)
y2 <- X %*% beta2 + rnorm(n)
y3 <- X %*% beta3 + rnorm(n)
# 设置交叉验证折数
k <- 10
# 设置不同的lambda值
lambda_seq <- 10^seq(10, -2, length.out = 100)
# 执行交叉验证和岭回归,并记录CV error和Prediction error
cv_error <- list()
pred_error <- list()
for (i in 1:3) {
# 交叉验证
cvfit <- cv.glmnet(X, switch(i, y1, y2, y3), alpha = 0, lambda = lambda_seq, nfolds = k)
cv_error[[i]] <- cvfit$cvm
# 岭回归
fit <- glmnet(X, switch(i, y1, y2, y3), alpha = 0, lambda = lambda_seq)
pred_error[[i]] <- apply(X, 2, function(x) {
x_mat <- matrix(x, nrow = n, ncol = p, byrow = TRUE)
pred <- predict(fit, newx = x_mat)
pred <- t(pred)
mean((x_mat %*% fit$beta - switch(i, y1, y2, y3))^2)
})
}
# 绘制图形
par(mfrow = c(3, 2), mar = c(4, 4, 2, 1), oma = c(0, 0, 2, 0))
for (i in 1:3) {
# CV error plot
cv_plot_data <- cv_error[[i]]
plot(log10(lambda_seq), cv_plot_data, type = "l", xlab = expression(log10), ylab = "CV error", main = paste0("Model ", i))
abline(v = log10(cvfit$lambda.min), col = "red")
# Prediction error plot
pred_plot_data <- pred_error[[i]]
plot(log10(lambda_seq), pred_plot_data, type = "l", xlab = expression(log10), ylab = "Prediction error", main = paste0("Model ", i))
abline(v = log10(lambda_seq[which.min(pred_plot_data)]), col = "red")
}
```
修正后的代码中主要是将 `%%` 运算符改为 `%*%`,使得矩阵相乘的维度匹配。此外,还对 `mean` 函数的参数进行了修改。
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