"I wonder which is more credible, your opinion or this study?"
You wonder because you are clueless and stupid. You submit a 'study' pushed by the notorious left-wing front FAIR as evidence that the media is not leftist. Please read the bio of FAIR's founder here:
http://www.fair.org/extra/writers/cohen.html
No doubt PRAVDA considers itself fair and balanced as well. FAIR exists only to combat the original, and far more compelling research of the MEDIA RESEARCH CENTER, found here:
http://www.mrc.org
For starters, do a little google search (once you are booted off FR and have the time) and look up the TIME magazine article in which nearly 80% of White House correspondents identified themselves as left of center. Then, my kitty-toasted butt monkey, ask yourself if you would consider it a problem if 80% of our national 'eyes and ears' in the national press club in Washington were members of the Nazi Party (well, technically the Nazi's are socialists so I suppose that diminishes my point somewhat).
Take a hike.