我在运行下面的代码时遇到错误。我只是尝试在特定分组中生成线性回归,并使用这些模型使用留一法生成估计值。有关如何解决此问题的任何建议?
library(modelr)
install.packages("gapminder")
library(gapminder)
data(gapminder)
#CASE 1
model1 <- lm(lifeExp ~ pop, data = gapminder)
model2 <- lm(lifeExp ~ pop + gdpPercap, data = gapminder)
models <- list(fit_model1 = model1,fit_model2 = model2)
gapminder %>% nest_by(continent, country) %>%
bind_cols(
map(1:nrow(gapminder), function(i) {
map_dfc(models, function(model) {
training <- data[-i, ]
fit <- lm(model, data = training)
validation <- data[i, ]
predict(fit, newdata = validation)
})
}) %>%
bind_rows()
)