crab:
Don’t install crab in this way: pip install crab / easy_install crab
You can find crab in pypi.python.org, this is not our scikits.crab source
Solution:
git clone https://github.com/muricoca/crab.git
python setup.py install

test: python -c “import scikits.crab as scc; scc.test()”

recsys:
sudo apt-get install python-scipy python-numpy
sudo apt-get install python-pip
sudo pip install csc-pysparse networkx divisi2

# If you don’t have pip installed then do:
# sudo easy_install csc-pysparse
# sudo easy_install networkx
# sudo easy_install divisi2

download from https://github.com/ocelma/python-recsys

tar xvfz python-recsys.tar.gz
cd python-recsys
sudo python setup.py install

csc package: http://pydoc.net/Python/csc-utils/0.6.3/
divisi2 package: http://csc.media.mit.edu/docs/divisi2/install.html
sudo pip install divisi2 csc-pysparse