I have been unsuccessfully trying to install the latest version (2.15.2) of r-base. Apparently, R package "Rcpp" would not install for R version 2.14.1 - the version that installs for me.

I am not sure what/how/where to change my installation attempts which appear below. Please note that I am using ubuntu-12.04.1-server-i386.

(1) ------------> The current installed version is R version 2.14.1 (2011-12-22)

sudo apt-get install r-base
Reading package lists... Done
Building dependency tree
Reading state information... Done
r-base is already the newest version.

(2) ------------> Including version information doesn't help:

sudo apt-get install r-base=2.15.1-5ubuntu1
Reading package lists... Done
Building dependency tree
Reading state information... Done
E: Version '2.15.1-5ubuntu1' for 'r-base' was not found

(3) -------------> Changes based on CRAN Ubuntu instructions
http://cran.r-project.org/bin/linux/ubuntu/README

3.1: Added to /etc/apt/sources.list
deb http://lib.stat.cmu.edu/R/CRAN/bin/linux/ubuntu quantal/

3.2: sudo apt-get update

3.3: sudo apt-get install r-base
Reading package lists... Done
Building dependency tree
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
r-base : Depends: r-base-core (>= 2.15.2-1quantal2) but it is not going to be installed
Depends: r-recommended (= 2.15.2-1quantal2) but it is not going to be installed
Recommends: r-base-html but it is not going to be installed
E: Unable to correct problems, you have held broken packages.