用的是RStudio3.1.2。根据老师给的内容，做了下面几个步骤：
data.dir <- "C:/Users/hs443/Dropbox/Academic/Teaching/Exeter/BEEM116/Term2-2015/data/"
data.filename <- "annual-data-shiller.csv"
data.filepath <- paste(data.dir, data.filename, sep="")
shiller.data <- read.table(data.filepath, header=TRUE, sep=",")

但是结果出现这样的情况：
Error in file(file, "rt") : cannot open the connection
In addition: Warning message:
In file(file, "rt") :
  cannot open file 'C:/Program Files/R/R-3.1.2/library/nlme/datacrsp-daily-ret-31Dec1925-31Dec2013.csv': No such file or directory
请教大家，这是怎么回事？