按国家划分数据，并在每个子集上创建线性回归模型 [英] Split data.frame by country, and create linear regression model on each subset

问题描述

我有一个来自世界银行的数据框，看起来像这样;

I have a data.frame of data from the World Bank which looks something like this;

  country date BirthRate     US.
4   Aruba 2011    10.584 25354.8
5   Aruba 2010    10.804 24289.1
6   Aruba 2009    11.060 24639.9
7   Aruba 2008    11.346 27549.3
8   Aruba 2007    11.653 25921.3
9   Aruba 2006    11.977 24015.4

总共有70个这个数据框中的一些国家/地区的子集喜欢运行线性回归。

All in all there 70 something sub sets of countries in this data frame that I would like to run a linear regression on.

如果我使用以下内容，我会为一个国家/地区获得一个不错的lm;

If I use the following I get a nice lm for a single country;

andora = subset(high.sub, country == "Andorra")

andora.lm = lm(BirthRate~US., data = andora)

anova(andora.lm)
summary(andora.lm)

但是当我尝试在for循环中使用相同类型的代码我将在代码下方打印一个错误;

But when I try to use the same type of code in a for loop I an error which I'll print below the code;

high.sub = subset(highInc, date > 1999 & date < 2012)
high.sub <- na.omit(high.sub)
highnames <- unique(high.sub$country)

for (i in highnames) {
  linmod <- lm(BirthRate~US., data = high.sub, subset = (country == "[i]"))  
}

错误消息：

Error in lm.fit(x, y, offset = offset, singular.ok = singular.ok, ...) : 
  0 (non-NA) cases

如果我可以得到这个循环来运行，我最好还要附加系数，甚至是将每个模型的r平方值转换为空的数据框架。任何帮助将不胜感激。

If I can get this loop to run I would ideally like to append the coefficients and even better the r-squared values for each model to an empty data.frame. Any help would be greatly appreciated.

感谢

Josh

推荐答案

这是对@ BondedDust的评论的一些修改。

This is a slight modification of @BondedDust's comment.

models <- sapply(unique(as.character(df$country)),
                 function(cntry)lm(BirthRate~US.,df,subset=(country==cntry)),
                 simplify=FALSE,USE.NAMES=TRUE)

# to summarize all the models
lapply(models,summary)
# to run anova on all the models
lapply(models,anova)

这将生成一个名为列表的模型，因此您可以将Aruba的模型提取为：

This produces a named list of models, so you could extract the model for Aruba as:

models[["Aruba"]]

这篇关于按国家划分数据，并在每个子集上创建线性回归模型的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！