无法安装“ baseballr”软件包

Question

我正在使用以下代码从GitHub安装baseballr软件包：

require(devtools)
install_github("BillPetti/baseballr")
require(baseballr)

但是，在运行require(baseballr)时，我始终收到以下错误消息：

Loading required package: baseballr
Warning message:
In library(package, lib.loc = lib.loc, character.only = TRUE, logical.return = TRUE,  :
  there is no package called ‘baseballr’

另外，当我运行install_github("BillPetti/baseballr")时，出现以下错误：

package ‘glue’ successfully unpacked and MD5 sums checked
Error: (converted from warning) cannot remove prior installation of package ‘glue’
In addition: Warning messages:
1: In untar2(tarfile, files, list, exdir) :
  skipping pax global extended headers
2: In untar2(tarfile, files, list, exdir) :
  skipping pax global extended headers

devtools已正确安装，但我不确定为什么baseballr无法正确安装。可以在here中找到该软件包的文档。